Atlas geological history of the barents sea by Norges geologiske undersøkelse

ATLAS

Geological History of the Barents Sea Geological History of the Barents Sea Morten Smelror, Oleg V. Petrov, Geir Birger Larssen & Stephanie C. Werner (editors)

Geological History of the Barents Sea

Svanemerket trykksak fra Skipnes Kommunikasjon.

Lisensnr. 241 731

ATLAS

Geological History of the Barents Sea

Morten Smelror, Oleg V. Petrov, Geir Birger Larssen & Stephanie Werner (editors)

Trondheim, Norway, Juni 2009 ISBN 978-82-7385-137-6 Geological Survey of Norway Editors: Morten Smelror, Oleg Petrov, Geir Birger Larssen & Stephanie Werner Authors: Valeri A. Basov, VNIIOkeangeolgia, Jörg Ebbing, NGU, Laurent Gernigon, NGU, Marianna V. Korchinskaya, VNIIOkeangeologia, Tatyana Koren, VSEGEI, Natalia V. Kosteva, PMGRE, Galina V. Kotljar, VSEGEI, Geir Birger Larssen, StatoilHydro, Tamara Litvinova, VSEGEI, Oleg. B. Negrov, VSEGEI, Odleiv Olesen, NGU, Christophe Pascal, NGU, Tatyana M. Pchelina, VNIIOkeangeologia, Oleg V. Petrov, VSEGEI, Yugene O. Petrov, VSEGEI, Hans-Ivar Sjulstad, NPD, Morten Smelror, NGU, Nikolay N. Sobolev, VNIIOkeangeologia, Victor Vasiliev, VSEGEI, Stephanie C. Werner, NGU Design and layout: Bjørg Svendgård, NGU Front cover design: Bjørg Svendgård Front cover photo: Odd Harald Hansen, NGU The photo is from Nordvestbukta, Bjørnøya. Printed in Norway by Skipnes AS Bound in Norway by Gjøvik Bokbinderi AS Paper: Proﬁ matt 130 gr Font: Celeste Publisher: Norges geologiske undersøkelse (Geological Survey of Norway) Tel.: +47 73 90 40 00 e-mail: ngu@ngu.no www.ngu.no

Fax: +47 73 92 16 20

Mys Sakhanina, Novaya Zemlya. Photo: Odd Harald Hansen

Contents Chapter 1

INTRODUCTION – EXPLORATION OF THE BARENTS SEA

Chapter 2

IMAGING DEEP STRUCTURES BENEATH THE SURFACE

Gravity

Magnetics

Derivates of the potential ﬁeld and structural interpretations

Geological structures seen on gravity and magnetic maps

Heat ﬂow of the Barents Sea

FROM RIFT - TO MEGA-BASINS

Top basement

Crustal thickness

Isostasy: compensation of sedimentary inﬁll

Isostatic Residual Map

CONTINENTS IN MOTION - THE BARENTS SEA IN A PLATE TECTONIC FRAMEWORK

Timanian and Caledonian orogenies and Late Devonian-Early Carboniferous times

Uralian Orogeny and subsequent Mesozoic times

Stable platforms and pre-breakup basins

North Atlantic break-up

Chapter 5

LOCHKOVIAN – Caledonian mountains in the west, and lowlands and shallow marine basins in the east

Chapter 6

FRASNIAN – Active rifting, and expansion of the marine basin in the east

Chapter 7

VISEAN – Extensive alluvial plains in the west and marine carbonate shelves and deep basins in the east

Chapter 8

MOSCOVIAN – Rising sea level and dryer climate

Chapter 9

ASSELIAN – Shallow carbonate shelves and deep basins

Chapter 10

WORDIAN – Temperate climate and extensive marine shelf

Chapter 11

INDUAN – Uralian uplift in the east and progradation into the shallow-water clastic shelf

Chapter 12

ANISIAN – Enclosed, restricted basins in the west, ﬂuctuating shorelines in the east

Chapter 13

CARNIAN – Orogen and uplift in the east, extensive westward coastal progradation

Chapter 14

HETTANGIAN – Wide continental lowlands

Chapter 15

TOARCIAN – Extensive coastal plains transgressed from east and west

Chapter 16

BAJOCIAN – Central uplift, maximum regression and prograding coastlines in the west and east

101

Chapter 17

TITHONIAN – Maximum transgression on an extensive shelf

105

Chapter 18

VALANGINIAN – Open marine shelf

109

Chapter 19

BARREMIAN – Tectonic uplift and prograding deltas in the north

113

Chapter 20

ALBIAN – Uplift in the northeast, deeply subsiding basins in the west

117

Chapter 21

EOCENE – Expanded hinterlands and shrinked basins

121

Chapter 22

LATE NEOGENE UPLIFT AND GLACIATIONS

125

Acknowledgements

128

Literature - References

129

Chapter 3

Chapter 4

Chapter 1

Introduction Exploration of the Barents Sea

Figtextvvklkløbkvløbkgløbkløbkvblønkbvln lø nlø

Guba Sakhanina, Novaya Zemlya. Photo: Odd Harald Hansen

Partcipants of the 11th International Geological Congress on excursion to Spitsbergen in 1910. Photo: Oscar Halldin, Geological Survey of Norway, NGU

The early explorers

In the Middle Ages, the Barents Sea was known

century. Fyodor Litke undertook four voyages

had experienced Late Tertiary uplift (approxi-

as Murmanskoye Morye, the Murman Sea, and

to Novaya Zemlya (1821—1824), and Pyotr Pa-

mately 500 m) and deep erosion. This ﬁrst

this name can be found on many sixteenth-cen-

khtusov travelled there twice, in 1832—33 and

model of uplift and erosion was based simply

tury maps, including Gerard Mercator’s “Map

1834-35, both times involving overwintering.

on the shallow bathymetry of the Barents Sea

of the Arctic” published in 1595. The Barents

These expeditions enriched the geographical

and the existing geological information about

Sea aquired its present name after the Dutch

sciences with reliable maps of the coastlines of

the surrounding land areas.

navigator and explorer Willem Barents. At the

the entire South Island and part of the North

In 1899 the ﬁrst icebreaker entered the Arc-

end of the sixteenth century, Willem Barents

Island; in the west up to Nassau Cape and as

tic seas. Under the ﬂag of Admiral Makarov,

led early expeditions to the far north in search

far as Dalny Cape in the east.

the “Yermak” reached Spitsbergen. Two years

of the North-East Passage to Asia, south of the

One of the more famous advances in the

later the ship made its way to Novaya Zemlya

Arctic Ocean. He discovered Svalbard and vis-

history of the Arctic was the expedition led

and Franz Josef Land. “Yermak” also made a

ited the Novaya Zemlya archipelago. His accu-

by the Norwegian explorer Fridtjof Nansen in

successful pioneer icebreaker voyage through

rate charting and valuable meteorological data

1893—96, with the mission to reach the North

the Northeast Passage. The same year, the

made him one of the most important of the

Pole, drifting with the vessel “Fram” in the ice

Norwegian polar explorer Roald Amundsen

early Arctic explorers.

and continuing on foot towards the pole. The

on the ship “Gjøa”, carried out oceanographic

In the following decades many generations

mission failed, but Nansen and his crew man-

observations in the Barents Sea, between No-

of explorers were attracted to the Arctic, with

aged to add a large amount of new informa-

vaya Zemlya and the Greenland Sea. In the

a strong desire to discover new land areas and

tion concerning the Arctic Ocean. During their

following years, there were several Norwegian

with the mission to try to ﬁnd sea routes con-

return Nansen and his assistant Hjalmar Jo-

expeditions to the Barents Sea, Svalbard and

necting the European, American and Asian

hansen overwintered on Franz Josef Land, and

Novaya Zemlya, including the research expedi-

continents. Some of the expeditions were also

Nansen brought with him collections of fossils

tion to Novaya Zemlya in 1921 led by the geolo-

planned to carry out various research tasks.

and rocks from Northbrook Island back to the

gist Olaf Holtedahl.

Several important Russian expeditions

museum in Oslo. In 1904 Nansen was the ﬁrst

into the Arctic were mounted in the early 19th

to suggest that the southwestern Barents Sea

Introduction

NOR WEG IAN SEA

A SV

R BA

YA Z E ML

74°0'0"N

76°0'0"N

78°0'0"N

Franz Josef Land

Bjørnøya

NOVA

72°0'0"N

BARENTS SEA

Topography 1 500 1 000

KARA SEA

750 500 250 100 50 25 0

70°0'0"N

-50 -100 -250

Pay Khoy

-500 -750 -1 000

Norway

-1 500 -2 000

68°0'0"N

-3 000 -4 000

Kolguyev

150

300

-5 000

Metre

Russia

Kilometers 30°0'0"E

Bathymetry 40°0'0"E

50°0'0"E

60°0'0"E

The Barents Sea (Norwegian: Barentshavet, Russian: БАРЕНЦЕВОМОРЕ, lies to the north of Norway and Russia, covers an area of 1.4 million km², and forms a part of the Arctic Ocean. It is a moderately deep shelf, bordered along the shelf edge towards the Norwegian-Greenland Sea in the west, the Svalbard archipelago in the northwest, and the Russian islands of Franz Josef Land and Novaya Zemlya in the northeast and east. Novaya Zemlya separates the Barents Sea from the Kara Sea to the east.

Sea-bed mapping Equally noteworthy are the activities in the

tic was explored on a regular and systematic

raphy, sediment composition, biodiversity,

Arctic in the early 20th century of the team of

basis, so that by the early 1940s there were no

habitats and biotopes as well as pollution on

military hydrographers led by Andrei Vilkit-

more “blank spots” left on the map of the Rus-

the sea-bed in Norwegian coastal and oﬀshore

sky, A. Varnek and N. Morozov, who made a

sian Arctic.

regions. The program was initiated to ﬁll gaps

large contribution to the Russian geographical

Today, high-resolution sea-bed mapping by

in our knowledge of sea-bed conditions and bi-

sciences. Seabed mapping in the Barents Sea

use of the modern multibeam echosounder is

odiversity as deﬁned in “The Integrated Man-

was completed in 1933, with the ﬁrst full map

being carried out in the southwestern parts of

agement Plan for the Marine Environment of

produced by Russian marine geologist Maria

Norwegian Barents Sea within the “Mareano-

the Barents Sea and the sea areas oﬀ the Lofo-

Klenova. Throughout the Soviet era, the Arc-

program”. MAREANO maps depth and topog-

ten Islands”.

Introduction

Exploration for hydrocarbon resources In a recent hydrocarbon assessment by the

Shtokmanovskoye ﬁeld in the Russian sector,

physical data have been accumulated. Most of

USGS, it has been estimated that about 30 % of

which is largest oﬀshore gas ﬁeld in the world.

our knowledge is based on industrial seismic

the world’s undiscovered gas and 13 % og the

Even though exploration activities have

data, potential ﬁeld data, and data from explo-

world’s undiscovered oil may be found in the

been going on for almost 40 years, knowledge

ration wells. In addition, there exists detailed

Arctic. The Timan-Pechora region is one of the

of the petroleum potential of the Barents Sea

information from continuously cored shallow

world’s most proliﬁc hydrocarbon provinces.

is still limited. In the Norwegian sector, fewer

boreholes on the Norwegian Barents shelf,

The adjacent Barents and Kara Seas also have

than 70 exploration and appraisal wells have

and from several onshore studies on Svalbard,

a proven, signiﬁcant, petroleum potential with

been drilled to date, and exploration in this

Franz Josef Land and Novaya Zemlya.

numerous giant discoveries. Although there

vast region is still regarded as being in its early

The main hydrocarbon source rocks are

are large uncertainties regarding the Russian

stage. NPD estimates the total undiscovered re-

present in the Upper Devonian, Upper Per-

estimates, there is nevertheless little doubt that

sources in the Barents Sea at 6.2 Bboe, with an

mian, Middle Triassic and Upper Jurassic

the potential is very substantial.

uncertainty range between 2.8 and 10.7 Bboe.

successions, while the most signiﬁcant res-

In the Barents Sea, hydrocarbon explo-

Oil in place is put at 1.25 Bboe. The Russian

ervoirs are proven in Devonian, Carbonifer-

ration began in the 1970s. Prior to the 1980s,

sector of the Barents Sea is estimated to con-

ous and Permian carbonates, and in Silurian,

exploration activity in the Norwegian sector

tain recoverable (P+P) resources of 430 MMbo,

Devonian, Carboniferous, Permian, Triassic,

included only seismic surveys and early NGU

180 MMbc and 96 Tcfg. The Shtokmanovskoye

Jurassic and Cretaceous sandstones. Major hy-

aeromagnetic surveys, as drilling north of the

ﬁeld, discovered in 1988, contains gas reserves

drocarbon plays in the Barents Sea have been

62nd parallel had not been authorised. Subse-

(ABC1 category) of some 90 Tcf and condensate

proven by the huge gas accumulations in Mid-

quently, discoveries were made on both the

reserves of 150 MMb in several Jurassic reser-

dle-Upper Jurassic sandstones in the Russian

Russian and the Norwegian sides. The ﬁrst

voirs. It is expected to be on-stream in 2010.

Shtokmanovskoye ﬁeld, and in Lower-Middle

major producing ﬁeld is Snøhvit in the Norwe-

During the last 25 years of exploration in

Jurassic sandstones in the Norwegian Snøhvit

gian sector. The largest discovery to date is the

the Barents Sea, substantial geological and geo-

ﬁeld. In the Timan-Pechora Basin oil discover-

The observatory on Heisa Island, Franz Josef Land. Photo: VSEGEI

Memoral stone of William Barentz on the northeastern side of Novaya Zemlya. Photo: Geir Birger Larssen

Polar bear swimming ashore on Franz Josef Land. Photo: VSEGEI

Introduction

ies in the Upper Palaeozoic dominate. The few

considered as exploration frontiers, and the

long time spans involving several sedimen-

wells in the Kara Sea have so far shown a good

tectonostratigraphic models linking the east-

tary cycles and facies changes) and/or based

potential for hydrocarbons in the Mesozoic.

ern and western Barents Sea are far from being

on limited datasets. The new project involves

thoroughly understood.

a synthesis of existing geological and geo-

Studies of outcrops in the Palaeozoic, Mesozoic and Tertiary successions on Sval-

In order to address this problem, the Geo-

physical data and their interpretation using

bard and from Novaya Zemlya and Franz Josef

logical Survey of Norway and the Russian Geo-

an interdisciplinary approach. By combining

Land have helped us to unravel the geological

logical Research Institute (VSEGEI) agreed to

new data from the most recent geophysical

history of the Norwegian and Western Rus-

carry out a joint project on the “Geological his-

surveys, exploration drillings and ﬁeldwork,

sian Arctic basins. By the introduction of 3D

tory of the Barents and Kara seas” – the Geo-

and closely integrating the regional geological

seismic surveys, a far better understanding of

BaSe project. The main is to produce reﬁned

and geophysical expertise held by the project

the internal morphology of the sedimentary

palaeogeographic models for the Barents Sea,

groups and collaborating partners, signiﬁ-

sequences and spatial facies distribution has

northern Pechora region and Kara Sea hydro-

cantly improved and higher-resolution palaeo-

been possible, as illustrated from recent stud-

carbon provinces. The project was joined by

geographic models are gradually being made

ies of the Upper Palaeozoic carbonate buildups

StatoilHydro as contributing and ﬁnancial

available through the present work. A series

on the eastern Finnmark Platform and the Tri-

partner, and by the Norwegian Petroleum Di-

of new paleogeographic maps is based on co-

assic, siliciclastic, shelf deposits in the south-

rectorate (NPD) as a contributing partner. The

herent interpretations of the entire Barents

western Barents Sea.

GeoBaSe project was further ﬁnancially sup-

Sea and Kara Sea region. Such an integrated

ported by the Norwegian Research Council’s

study of the geological history is expected to

Petromaks-programme.

lead to a better understanding of the spatial

The expectations for future discoveries are high. However, there are still many gaps in our knowledge of the geological history and ba-

Prior to our joint project, the published pal-

distribution of hydrocarbon source rocks and

sin evolution in this geographically very large

aeogeographic reconstructions were generally

reservoir rocks in this extensive Arctic region.

area. Major parts of the region are still to be

rather rough (i.e., each map covers relatively

Participants of the GeoBaSe-project and the NORGEX expedition to Svalbard in July 2006. Photo: NGU

Ammonite collected at Northbrook Island on Franz Josef Land by the Norwegian explorer Fridtjof Nansen. Photo: Geological Museum, Oslo.

Introduction

Chapter 2

Gravity and magnetic measurements are remote-sensing methods and are made in order to study structures beneath the Earthâ&#x20AC;&#x2122;s surface by measuring the effect of different physical properties of rocks (density and magneti-sation) in the subsurface.

Imaging deep structures beneath the surface

geological eﬀects on gravity (tidal variations,

the data sets. For the entire territory of the

Earth rotation, distance from the Earth’s centre

former USSR, a gravity map on the scale 1: 2

and topographic relief) are removed, thereby

500 000 is provided by VNIIGeophysika.

correcting for the Earth’s normal gravity ﬁeld.

To homogenise the data measured in the

A gravity anomaly is what is left, and an anom-

Russian and Norwegian parts of the Barents

aly map reﬂects mainly the unknown compo-

Sea, the geodetic reference systems for the Rus-

sition and structure of the outer shell of the

sian data set (projection reference: Pulkovo

Earth, the lithosphere, the part that is of most

1942; normal gravity formula: Helmert 1901)

interest for geologists (see info box: Interpreta-

were transferred into the International Grav-

tion of gravity anomalies).

ity Standardization Net 1971 (IGSN 71), and

To compare gravity anomalies measured

the Gravity Formula of 1980 for determining

at diﬀerent elevation, the measurements must

normal gravity were used for the derivation of

be corrected for the gravity eﬀect caused by

anomaly values for the entire map. The data

height diﬀerences. The gravity anomaly, which

was cross-checked against satellite gravity

is corrected for the height above the reference

data. The combined data set has been inter-

level, is called the free-air gravity anomaly and

polated to a square cell of ten-kilometre size

essentially corresponds to a measurement at

using a minimum curvature method. The ﬁnal

zero elevation, which is roughly the ocean sur-

grid was also low-pass ﬁltered with a cut-oﬀ

face. On land, corrections are also needed for

wavelength of 20 km. The resulting data set has

the mass between the observation point and

a good aerial coverage for the Barents Sea, an

the zero elevation. This gravity anomaly is

advantage compared to seismic data which are

called the Bouguer gravity anomaly and is the

more focused on certain areas.

standard for geological interpretations. In the

Ideally, the gravity data for Novaya Zemlya

Barents Sea, the interpretation of gravity data

and Svalbard need to be corrected for the per-

assists in the linkage of structural information

manent ice cover. Simple assumptions of the

from the eastern and western parts of the Bar-

ice thickness on Novaya Zemlya indicate that

ents Sea, across the border between Norway

the gravity eﬀect of the ice cover is as high as

and Russia, where seismic data are not avail-

20 mGal, and hence makes a signiﬁcant contri-

able.

bution to the gravity anomaly.

The gravity data presented here for the western part of the Barents Sea are based on land and shipborne measurements provided by the Geological Survey of Norway (NGU), the Norwegian Mapping Authority, the Norwegian Petroleum Directorate, TGS-NOPEC Geophysi-

Imaging deep structures at the surface

150

30°0'0"E

40°0'0"E

50°0'0"E

60°0'0"E

30°0'0"E

40°0'0"E

50°0'0"E

300

Kilometers

150

300

Kilometers

10 0

tions have worked on the homogenisation of

60°0'0"E

12 0 > 14 0

tance along the lines. Diﬀerent Russian institu-

When measuring gravity, all known non-

almost all depths.

10-20 km line separation and 3-4 km point dis-

60°0'0"E

of the Barents Sea on a network of proﬁles with

pared to the surrounding sedimentary rock, at

50°0'0"E

the large negative density contrast of salt com-

40°0'0"E

out systematic, shipborne, gravimetric surveys

30°0'0"E

-4 0 -2 0

vey”, MAGE PGO ”Sevmorgeologia” has carried

ple, salt structures are easy to detect because of

300

-6 0

mineral and petroleum exploration. For exam-

150

<10 0 -8 0

years. In the program “World Gravimetric Sur-

72°0'0"N

metric surveys conducted over a period of 20

gravity method has been used widely for both

70°0'0"N

derstand their formation. On a local scale, the

68°0'0"N

compiled on the basis of medium-scale gravi-

Kilometers

78°0'0"N

extension and depth of basins and to better un-

76°0'0"N

re-digitising contour maps. These maps were

74°0'0"N

gravity measurements can be used to study the

72°0'0"N

geologia provided these gravity data by partly

70°0'0"N

Research Institute (VSEGEI) and VNIIOkean-

is needed for navigation. On a regional scale,

68°0'0"N

ly the rotation and shape of the Earth, which

78°0'0"N

areas, the Karpinsky All-Russian Geological

76°0'0"N

For the eastern Barents Sea and Kara Sea

gravity ﬁeld is important to determine precise-

74°0'0"N

a global scale, understanding the details of the

72°0'0"N

gian and international universities.

70°0'0"N

cal Company and contributions from Norwe-

of scales and for many diﬀerent purposes. On

68°0'0"N

Gravity measurements are used at a wide range

74°0'0"N

76°0'0"N

78°0'0"N

Gravity

mGal

A) The map shows the free-air gravity anomaly field (EIGENGL04C) as derived from observations from CHAMP and GRACE satellite missions, based on the flight height (about 300 km or more) of the satellite. Such models describe only very longwavelength anomalies, as gravity decreases with the distance (1/R2) to the source. B) The free-air gravity anomaly map derived from the Earth gravitational model (EGM2008), that incorporates surface and satellite measurements. C) The Bouguer gravity anomaly map of the Barents and Kara Seas, calculated from the free-air gravity model EGM2008. The terrain-corrected Bouguer anomaly values are computed using a rock density of 2670 kg/m3. The westernmost part is characterised by high-amplitude positive anomalies, marking the continental shelf edge (the abrupt transition between shallow sea and deep oceanic units). Farther to the east, small-scale anomalies are visible, which are associated with basin structures and salt domes. The eastern (Russian) part of the Barents Sea is characterised by medium-scale anomalies, which have been partly attributed to extraordinarily deep and extensive basin structures.

Legend 78°0'0"N

Norwegian Gravimetric Surveys Offshore gravimetric profiles Onshore measuring points

Russian Gravimetric Surveys 76°0'0"N

Gravimetric map (scale 1:6 000 000) Gravimetric map (scale 1:2 500 000)

68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

Gravimetric map (scale 1: 200 000)

150

Map of the gravity measurement sources. For the western Barents Sea, this map shows the station density and the ship-tracks along which gravity was measured. For the eastern Barents Sea, the distribution of map-sheets, which were re-digitised for this Barents and Kara Seas compilation, are shown.

300

Kilometers 30°0'0"E

40°0'0"E

50°0'0"E

60°0'0"E

Interpretation of gravity anomalies Observed gravity anomalies are a direct indication of density variations in the subsurface that are related to different densities of the material. These rocks can be located close to the Earth’s terrestrial surface or sea floor, or at depths ranging from about 10 m to more than 100 km. The gravity surveying process measures the sum of all lateral density contrasts at all depths. Data filtering allows one to isolate portions of the gravity anomaly signal that are of geological or exploration interest. The important parameter in gravity investigations are the density differences in the subsurface. For the interpretation of gravity anomaly maps, subsurface models can be constrained by seismic and geological data. A straightforward interpretation of such maps is often not possible, because of complex subsurface situations and ambiguous solutions for depth and shape relationships.

Gravity Anomaly

3 2

Depth

Ambiguity and superposition of potential field sources. (Left) The same gravity anomaly (here positive) can be caused by multiple sources at different depths. (Right) The observed gravity anomaly changes in width and amplitude depending on the burial depth, even though the body has the same shape and density contrast. Therefore, additional information from geology and seismic data are useful to better interpret the observed gravity anomaly.

Imaging deep structures at the surface

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

Kilometers

14 0

60°0'0"E

12 0

10 0

50°0'0"E

-2 0

300

-4 0

150

-6 0

-8 0

40°0'0"E

<10 0

30°0'0"E

mGal

The gravity anomaly map of the Barents and Kara Seas. On land, the combined data sets consist of terrain-corrected, Bouguer anomaly values computed using a rock density of 2670 kg/m3. For the oceanic area the free-air anomaly is retained.

Imaging deep structures at the surface

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

-3 00 <40 0

60°0'0"E

-2 00

-1 00

-5

50°0'0"E

10 0

20 0

300

30 0

150

40 0

50 0

40°0'0"E

60 0

30°0'0"E

Kilometers

Magnetic anomaly map of the Barents and Kara Seas. The combined data set has been interpolated to a square cell of five-kilometre size using a minimum curvature method.

Imaging deep structures at the surface

S N

Simple illustration of the Earth’s normal magnetic field, which as a first approximation is similar to the magnetic field of a bar magnet (dipole) located in the Earth’s centre. The presentday, Earth’s magnetic field axis has 11 degrees deviation from the rotation axis of the Earth.

Magnetics In a similar manner to gravity maps, magnetic

For the interpretation of magnetic anomaly

mally ﬂown using a magnetometer attached to

anomalies reﬂect lateral variations in the dis-

maps, not only the structure of the crust but

an aircraft. The total intensity of the magnetic

tribution of subsurface rocks and can be used

also the time of rock formation is important.

ﬁeld is then measured along ﬂight lines with

to interpret changes in structure and rock type

Magnetisation can vary greatly in the same

varying spacing. Most of the Norwegian Bar-

at depth. In this case, density is not the im-

rock type, due to diﬀerences in the external

ents Sea has been measured at ﬂight altitudes

portant property, rather it is the magnetisation

magnetic ﬁeld when the rock was formed, and

ranging from 200 m to 1500 m.

of a rock. Magnetisation is a varying response

to variations in the content of magnetic min-

Over the eastern Barents Sea, most aero-

of materials in the Earth’s magnetic ﬁeld and

erals. Such magnetisation is often associated

magnetic surveys were carried out by VNI-

depends, for example, on the amount of tita-

with remanent magnetisation, a type of mag-

IOkeangeologia (NIIGA), Polar geophysical

nium and iron present in oxide minerals and

netisation that would also be present in the

expedition NPO ”Sevmorgeo” and FGUP ”Sev-

the degree of metamorphism to which a rock

absence of an external magnetic ﬁeld.

morgeologia” between 1967 and 2000. The cov-

has been subjected.

To study magnetic anomalies associated

erage over the Russian part of the Barents Sea

The Earth’s magnetic ﬁeld changes with

with geological structures, the eﬀect of the

is shown in upper ﬁgure on next page. Meas-

time and ultimately leads to reversals of this

Earth’s normal magnetic ﬁeld must be removed.

urements were carried out at ﬂight levels of

same ﬁeld. Such ﬁeld reversals occur on geo-

Magnetic ﬁeld models of the Earth are calcu-

300, 600 and 3000 m. The line separation was

logical time scales and are recorded on the

lated from observatory measurements to give

typically between 5 and 10 km. The mean least

ocean ﬂoor. At mid-ocean spreading ridges,

the so-called International Geomagnetic Refer-

square errors of the aeromagnetic surveys are

the direction of the ambient magnetic ﬁeld at

ence Fields (IGRF). Due to the change in the

in the order of 11 - 14 nT.

the time of formation is ‘frozen’ into the cool-

ﬁeld with time, the IGRF is updated every ﬁve

The resulting aeromagnetic anomaly map

ing magma. As a result, a series of stripes in

years. Short-term variations such as magnetic

allows us to characterise the basement underly-

the total intensity anomalies run parallel to

storms, which in the Arctic regions are visible

ing the sedimentary basins, as well as to iden-

and symmetrically on either side of the cen-

as northern lights (aurora borealis), need to be

tify diﬀerent domains as expressed by diﬀer-

tral ridge, and these are interpreted as alternat-

monitored during the survey and corrected for.

ent characteristics in the magnetic anomalies

ing blocks of normal and reversely magnetised

Such magnetic variations are not predictable.

(see info box).

oceanic crust. Rocks formed at a certain time

NGU and TGS-NOPEC Geophysical Compa-

‘remember’ the actual magnetic ﬁeld at that

ny have covered large parts of the Norwegian

time, despite having moved or being subjected

Barents Sea and Svalbard with aeromagnetic

to magnetic ﬁeld changes.

measurements. An aeromagnetic survey is nor-

Imaging deep structures at the surface

Legend

76°0'0"N

78°0'0"N

Russian Area Survey (Year)

Norwegian Area Survey (Year)

1987

2001

1991

2002

1999

2003

1998

2004

1999

2005

74°0'0"N

1999 1976

SX 2

1962

SVA 1991

1983

SPA 1988

1980

SEV 1989

1975 2000 72°0'0"N

1976 1973

SEV 1989 NGU 1970 NGU 1969 BSA 1987

1985 BAMS 1967 70°0'0"N

1971 1971 1972

68°0'0"N

1982-84 0

150

300

Kilometers 30°0'0"E

40°0'0"E

50°0'0"E

60°0'0"E

Overview of the aeromagnetic surveys in the Barents and Kara Seas. Various airborne surveys have been performed over the past 50 years.

Interpretation of magnetic anomalies Rocks can ’remember’ the magnetic field direction at the

time when they were formed, but the intensity of mag-

netisation depends on the type and amount of magnetic

minerals a rock contains. This magnetisation is called re-

manent magnetisation. The second contribution of rock

-2 -40

magnetisation is called induced magnetisation and ex-

8 I = 90

-20

I = 60

-20

ists only in the presence of an external magnetic field, such as that on Earth, which allows one to use a compass to find the north direction. 8

The magnetic effect of a dipole (bar magnet), whose magnetisation is induced and aligned with the Earth’s mag-

I = 30

netic field, is shown as total (solid) and vertical (dashed)

magnetic anomalies. Depending on latitude, these two

-2 -40

curves deviate the farther the observation point is situ-

-20

I=0

ated from the pole (i = 90˚). For interpretations, verticalfield curves are commonly used. Total-field and verticalfield curves are similar in high magnetic latitudes, such as those for the Barents Sea, and no further corrections are needed for an interpretation. Nevertheless, in interpreting magnetic anomalies, a combination of remanent and induced magnetisation always needs to be considered.

Imaging deep structures at the surface

Derivatives of the potential ﬁeld and structural interpretations Structural interpretations can be based on

and negative anomalies in the second-order

gravity and magnetic anomaly maps and their

derivatives. II. Baltic Shield (pink). This unit

ﬁrst and second derivatives. Such derivative

is characterised by positive gravity anoma-

maps make an interpretation of the potential

lies or an anomaly ﬁeld with broad negative

ﬁeld maps easier, as they enhance the gradi-

anomalies, containing locally positive anoma-

ents/changes in the potential ﬁelds that re-

lies. III. Eastern Barents Sea basins (bright

ﬂect changes in rock properties. These maps

green): This unit is characterised by a grav-

are especially useful for mapping the struc-

ity ﬁeld with positive and negative anomalies

tural outline of the bodies in the subsurface

and a unit with anomalies of medium intensity

that cause the observed anomalies. The val-

against a weak negative background ﬁeld. IV.

ues represented in tilt-derivative maps can be

Timan-Pechora (dark brown), which is char-

used to calculate the location of potential ﬁeld

acterised by a weak positive gravity anomaly

sources, or simply for structural mapping. The

ﬁeld with positive and with negative anomaly

ﬁgures on the next two pages show a tenta-

zones with intensive local positive anomalies.

tive structural-morphological interpretation

V. Novaya Zemlya fold system (orange). This

of the gravity and magnetic anomaly maps,

domain is characterised by negative anomalies

respectively. Based on a qualitative compari-

and a gravity ﬁeld with intensive positive and

son of the ﬁeld anomaly and its derivatives,

large negative anomalies. VI. Franz Josef Land

domains with similar anomaly characteristics

domain (dark green) is characterised by posi-

can be outlined. For the interpretation, the in-

tive and locally strongly positive anomalies

tensity of the anomalies (positive or negative),

and regional anomalies with medium intensity.

the direction and strike of the tilt derivative

Magnetic-based domains: I. Western

lineaments and the change in frequency can

Barents Sea (blue) characterised by intensive

be used. Derivative maps can also be used to

positive magnetic anomalies. II. Baltic Shield

analyse the quality of the data compilation, as

(pink). This unit is characterised by high-inten-

boundaries between areas with diﬀerent line

sity, negative and positive anomalies against

spacing will be visible.

a background of broad positive anomalies.

Based on the derivative images, six diﬀer-

III. Eastern Barents Sea basins (green). This

ent domains can be observed in the gravity

unit is characterised by anomalies of low in-

anomaly map. These domains correlate well

tensity against a generally reduced magnetic

with information about the tectonic setting de-

background. IV. Timan-Pechora (light brown)

rived from other sources. The interpretation of

characterised by strong positive and nega-

the magnetic anomalies leads to the identiﬁca-

tive anomalies. V. Novaya Zemlya fold system

tion of eight domains with diﬀerent magnetic

(dark brown), which is characterised by areas

patterns. When comparing the interpretation

of negative magnetic anomalies of intermedi-

of the gravity and magnetic anomaly maps,

ate intensity, and strong positive anomalies.VI.

one can observe diﬀerences in many details.

Franz Josef Land area (yellow) characterised

This is because the same rock formations do

by intermediate negative anomalies against

not necessarily produce corresponding gravity

a background of high positive intensity. VII.

and magnetic anomalies. Therefore, it is use-

Transitional area between Novaya Zemlya and

ful to ﬁrst interpret the gravity and magnetic

Kara Sea (orange), which can only be seen in

anomalies independently, and in a second step

the magnetic anomaly ﬁeld. This unit is char-

to identify similar anomalies. For example, the

acterised by areas of positive and negative

transition from the southwestern Barents Sea

anomalies of low intensity and intermediate

to the Baltic Shield can be identiﬁed on both

negative anomalies. VIII. Pay-Khoy fold sys-

interpretational maps.

tem (light green), characterised by a magnetic

Gravity-based domains: I. Western

ﬁeld with dominating intermediate negative

Barents Sea (blue), characterised by intensive

and middle to high-intensity, positive magnetic

positive anomalies in the gravity anomaly,

anomalies.

weak positive signal in the ﬁrst derivatives,

The Northern lights. Photo: Bjørn Jørgensen Imaging deep structures at the surface

Geological structures seen on gravity and magnetic maps

The seaﬂoor of the Barents Sea is generally ﬂat

is observed (e.g. Senja Ridge and Veslemøy

resolution of the magnetic anomaly map pre-

with a depth less than 500 metres. Only a few

High). One obvious example of a positive grav-

sented here does not allow identifying these

features are visible: relics of the latest phase

ity anomaly, (positive) magnetic anomaly and a

expected anomalies. Also in the deep Eastern

of the ice age, during which large glaciers and

correlation with exposed magmatic rock types

Barents Sea the presence of deep-seated sills

meltwater carved their path in the sediments,

is found around Sørøya, Seiland, Stjernøya,

is known, which are also not reﬂected in the

but also deposited new sediments on top. Grav-

and the nearby Øksfjord peninsula. Such a re-

magnetic anomaly map, as they are emplaced

ity and magnetic maps therefore are useful for

lationship between magmatic rocks and posi-

in depths greater than 5 km and have typically

studying the geological units below the sedi-

tive magnetic anomalies can also be found oﬀ-

a thickness of less than 500 m.

mentary overburden.

shore between Svalbard and Franz-Josef Land,

A high magnetic anomaly which does not

While the gravity map is useful for under-

although the two magmatic provinces are not

correlate directly with the known geological

standing density variations, the magnetic map

related. These latter magmatic rocks possibly

structure of the Barents Sea, but which may

represents variations in the magnetisation.

continue towards Franz-Josef Land, but the

hold the key to the understanding of its tecton-

Generally, sediments have very low magnetisa-

resolution of the magnetic map there is too

ic history and more speciﬁc, the understanding

tion, but the underlying rocks are magnetised,

low. Some of these magmatic-related anoma-

of the Eastern Barents Sea basins, is located

implying that the sediments seem to be trans-

lies could also be associated with gravity highs,

in the central Barents Sea, directly adjacent to

parent. As discussed in the previous section

but again the resolution here is limited and a

the wester margin of the Eastern Barents Sea

such maps can be used to deﬁne domains, but

clear correlation is not possible.

basins. This anomaly is located directly on the

smaller features can also be interpreted. For

In the westernmost part of the Barents Sea

transition between the Eastern and Western

example, near the Billefjord Fault Zone, which

and also in the far north (not shown on the

Barents Sea, where apparently a change in the

crosses Svalbard from north to south, a promi-

map), the transition between shallow conti-

style of basin formation occurs.

nent positive magnetic anomaly is visible and

nental shelf and deep ocean is marked by a

represents most likely an upthrusted slice of

strong positive gravity anomaly. These gravity

Hecla Hoek basement. On the other hand, the

anomalies represent partly the approximately 2

strike-slip Trollfjorden-Komagelva Fault Zone,

km thick sedimentary wedges deposited along

located onshore Norway does not have an ex-

the Barents Sea continental margins during

pression in the magnetic map at this resolution.

the Plio-Pleistocene glaciations. The weight of

Many of the positive magnetic anomalies in

these wedges cause present day subsidence and

the Barents Sea area are associated with base-

seismicity on the continental margin and adja-

ment highs, e.g. the Ludlov Saddle, Loppa High

cent oceanic crust. Farther onto the shelf, many

and Stappen high. The latter two anomalies

small-scale negative anomalies are associated

represent a continuation of the regional mag-

with graben structures, other basins ﬁlled with

netic anomalies in Troms and Nordland and are

sediments and salt diapirism. Sediments and

interpreted to reﬂect the northward continua-

salt have lower densities than the surrounding

tion of the c. 1.8 Ga Transcandinavian Igneous

material and are, therefore, discernible as nega-

Belt extending all the way to southern Sweden.

tive anomalies. Such basins include the Nord-

The local oﬀshore maxima are partly related

kapp, Maud and Harstad basins.

to basement highs that are conﬁrmed by coin-

A peculiar feature in the magnetic anomaly

ciding positive gravity anomalies, e.g. for the

map, that is not visible on the gravity map, is a

Loppa and Stappen Highs, and also observed

series of small-scale anomalies east of Svalbard.

on seismic data. The coinciding magnetic and

These anomalies close to the transition from

gravity anomalies may represent metamorphic

continental shelf to oceanic area are related to

core complexes formed during exhumation of

magnetic intrusions (sills) into the continental

lower crustal rocks along low–angle detach-

shelf. Such sill intrusions are a typical feature

ments zones resembling the tectonic situation

at the border of most passive margins and can

along the Lofoten-Vesterålen margin further to

be observed all along the edges of the Norwe-

the south. Other highs are deﬁned by positive

gian shelf. Such sills would also be expected

gravity anomalies, but no clear correlation with

further to the east, and have been imaged by

either positive or negative magnetic anomalies

seismic and high-resolution magnetic data. The

Imaging deep structures at the surface

The relief of the Barents Sea. Structural and tectonic features are superposed for comparison. The gravity and magnetic anomaly maps include prominent features such as basins and basement highs. These features are not necessarily recognised in the relief, but can be detected on such maps.

Franz Josef Land

NOR DIC SEA

Vest bakk en

70°0'0"N

Hammerfest Basin

Norway

n h asi Hig pB el ap s k r d r No No

Finnmark Platform Tr ol lfjo rd -K om ag el v Fa ul tZ on e

Central Barents High

Paleozoic Proterozoic

1 500 1 000 750

KARA SEA

NOVA

h Hig pa p Lo

Ludlov Saddle

BARENTS SEA

igh sH riu u c er M

Mesozoic

YA Z E ML

Perseus High

Bjarmeland Platform Mau d Ba sin

h Hig en ank b l tra Sen

Gardarbanken High

s Ba

om Tr sin Ba tad s r Ha

Ad mi ra lity Hi gh s

Cenozoic Olga Basin

Basin Sørkapp

Bjørnøya gh Hi en p ap St sin Ba a y nø ør Bj

Bas Ri dg e

Tectonic Structures General

Se nj a

Kong Karl Platform North Barents Basin

aget estn Sørv

72°0'0"N

Svalbard Platform

y mø sle Ve igh H

sø

A LB

en nk ba or igh t S H

74°0'0"N

76°0'0"N

78°0'0"N

SCW

South Barents Basin

500 250 100 50 25 0

Var a Bas nger in

-50 -100 -250 -500

Pay Khoy

-750 -1 000 -1 500 -2 000 -3 000

68°0'0"N

Kolguyev

150

-5 000

Russia

Kilometers

Pechora Basin 40°0'0"E

50°0'0"E

60°0'0"E

300

150

300

60°0'0"E

-5 0 -1 00 -2 00 -3 00 <40 0

10 0

50°0'0"E

40°0'0"E

20 0

30°0'0"E

30 0

60°0'0"E

40 0

14 0

12 0

50°0'0"E

10 0

40°0'0"E

-4 0 -2 0

-6 0

Kilometers 30°0'0"E

<10 0 -8 0

60 0

150 Kilometers

50 0

68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

76°0'0"N

78°0'0"N

30°0'0"E

68°0'0"N

-4 000

300

Imaging deep structures at the surface

Areas Area of Spitsbergen anticline, characterised by differentiated weak positive (b) GF with intensive positive (a) and negative (c) anomalies

I a

Area of the Baltic Shield, characterised by differentiated positive (a) GF with large negative (b) anomaly and local positive anomalies

Area of the Barents Sea basins, characterised by differentiated GF with positive (a) and negative (c) anomalies of middle intensity against a weak negative background (b)

III a

78°

* GF – gravity field

IV b

VI b

Area of the Pechora Plate, characterised by differentiated weak positive (b) GF with positive (a) and negative (c) anomalous zones and intensive local positive anomalies

Area of the Novaya Zemlya fold system, characterised by differentiated negative (b) GF with intensive positive (a) and negative (c) large anomalies

74°

Area of Franz Josef Land, characterised by differentiated positive (c) GF with intensive positive (b) anomalies and local anomalies of middle intensity

Boundaries anomaly zones

main

local uplifts

Structural Lines Axes of anomalies positive: a - 1st order, b - 2nd order** negative: a - 1st order, b - 2nd order**

70°

Lines of correlation disturbance ** Anomaly axes of the 2nd order are revealed after the anomalies of gravity field from –30 to 30 mGal; anomaly axes of the 1st order are revealed after the anomalies of gravity field below –30 and above 30 mGal

Other Symbols a

Local anomalies: a - positive, b - negative

18°

68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

76°0'0"N

78°0'0"N

150

300

Kilometers 30°0'0"E

Magnetic map.

Imaging deep structures at the surface

40°0'0"E

50°0'0"E

60°0'0"E

0°

6°

12°

18°

24°

30°

36°

42°

48°

54°

60°

66°

72°

78°

74°

III I

70°

IV °

24°

30°

36°

42°

48°

54°

60°

Structural interpretations of the gravity anomaly map and its derivatives. Interpretation T. Litvinova, VSEGEI

60°0'0"E

Horizontal tilt derivative.

Vertical tilt derivative. Imaging deep structures at the surface

78°

74°

VIII

III

VII

70°

18°

24°

30°

36°

42°

68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

76°0'0"N

78°0'0"N

Structural interpretations of the magnetic anomaly map and its derivatives. Interpretation T. Litvinova, VSEGEI

150

300

Kilometers 30°0'0"E

Gravity map.

Imaging deep structures at the surface

40°0'0"E

50°0'0"E

60°0'0"E

Horizontal tilt derivative.

48°

54°

60°

Areas I II

74°

Area of Spitsbergen anticline, characterised by the prevalence of positive intensive magnetic anomalies Area of the Baltic Shield, characterised against a background of a large positive intensive magnetic anomaly by differentiated intensive negative and positive magnetic anomalies

III

Area of the Barents Sea Basin, characterised by anomalies of low intensity against a general reduced AMF background

Area of the Pechora Plate, characterised by large intensive positive and negative magnetic anomalies

Area of the Novaya Zemlya fold system, characterised by areas of negative magnetic anomalies of middle intensity and positive anomalies of high intensity

Area of Franz Josef Land, characterised by negative anomalies of middle intensity against a background of AMF of high intensity

VII

VIII VIII

Transitional area distinguished after AMF, characterised by areas positive and negative anomalies of low intensity and negative anomalies of middle intensity Area of Pay Khoy fold system, characterised by differentiated AMF with prevalence of middle-intensive negative and middleand high-intensive positive anomalies

*AMF- anomalous magnetic field

Boundaries main

other

of blocks

Structural Lines 70°

Axes of anomalies a b

positive: a - 1st order, b - 2nd order**

a b

negative: a - 1st order b - 2nd order** Lines of correlation disturbance

**Anomaly axes of the 2nd order are revealed after the anomalies of magnetic field from –100 to 100nT; anomaly axes of the 1st order are revealed after the anomalies of magnetic field below –100 and above 100 nT

Other Symbols Area of reduced low-intensive AMF*

Vertical tilt derivative. Imaging deep structures at the surface

Heat ﬂow of the Barents Sea ments at sea-bottom, (2) temperatures measured in deep exploration wells now released by the Norwegian Petroleum Directorate, and (3) four heat-ﬂow measurements in shallow wells

Svalbard

made by Sintef Petroleum Research (i.e. former IKU) in the 1980s. Marine heat-ﬂow studies focused on the continental-ocean transition and the oceanic

Atlantic Ocean

crust of the NE Atlantic, where the sea-bottom is deep enough in to neglect disturbances caused by short-term variations in seawater temperatures. The marine data show the expected increase in heat ﬂow from the Barents Shelf towards the Knipovich and Mohns ridges. Because the Knipovich Ridge comes close to the

Barents Sea

continent at the Svalbard Margin, the variation in heat ﬂow from the continent to the ocean is dramatically sharper there than farther to the south. As a consequence, large amounts of heat are expected to be transferred from the Knipovich Ridge to the adjacent Svalbard Margin. This, in turn, suggests that the Moho heat-ﬂow in the region of the Svalbard archipelago is much higher than elsewhere in the Barents Sea region.

y rwa No

The occurrence of Miocene to Pleistocene basaltic volcanism and present-day hot springs in northern Spitsbergen adds geological support to this hypothesis. Farther to the south, the SW Barents Sea meets older oceanic crust and heat-ﬂow values are generally lower than those measured at

Locations of heat-flow measurements in the western Barents Sea. Solid circles: marine heat-flow measurements (Sources: Crane et al. 1982, 1988, Sundvor 1986, Sundvor et al. 1989, Eldholm et al. 1999); inverted triangles: released IKU shallow drilling measurements (Sources: Zielinski et al. 1986, Sættem 1988, Løseth et al. 1992); open circles: locations of exploration wells for which temperature data are available (www.npd.no). KR = Knipovich Ridge, MR = Mohns Ridge.

higher latitudes. Local heat-flow maxima (up to 1000 mW/m2!) are not representative of stable geothermal conditions but are caused by gas and fluid seepage. Most of the determined heat-flow values in the ocean remain in the

The thermal state of the Barents Sea shelf ap-

reservoirs occur mainly within the so-called

range between 50 and 70 mW/m2 and agree

pears to be variable and dominated by a NW-SE

Golden Zone, which is limited to the tempera-

reasonably well with the age of the underlying

trend. Maximum heat-ﬂow values aﬀect mainly

ture interval 60 °-120o °C. Approximately half of

basement (i.e. 33 to 43 Ma). In the SW Barents

the Svalbard archipelago region where recent

the heat ﬂow in thermally relaxed sedimentary

Sea, similar heat-ﬂow values were determined

volcanism and present-day geothermal activity

basins (i.e. older than 60 Myr) originates in

from shallow drilling projects carried out by

are observed. Heat-ﬂow values in the SW Bar-

the crystalline basement, while the other half

IKU, suggesting that this region of the Barents

ents Sea are in the range between ~50 and ~70

comes from the mantle. The age and thickness

Shelf is characterised by ’normal’ continental

mW/m and can be considered as ’normal’ for

of the lithosphere also aﬀects surface heat ﬂow.

heat-ﬂow values of ~60 ± 10 mW/m2 (the highest

IKU value being 74 mW/m2). The compilation

a Phanerozoic sedimentary basin. In agreement

of available Bottom Hole Temperatures (BHT)

with long-wavelength gravity anomalies (i.e. suggesting a gradual deepening of the base of the lithosphere), heat-ﬂow values seem to decrease

Geothermal state of the western Barents Sea

towards the east (i.e. ~50 mW/m2) and reach typi-

that the geothermal state of the SW Barents Sea does not present, at ﬁrst glance, any peculiar-

Available public data documenting the present-

ity with respect to other sedimentary basins

Understanding heat-ﬂow variation in sedi-

day geothermal state of the western Barents Sea

worldwide. Indeed, the estimated geothermal

mentary basins is of importance for the suc-

consists mainly of (1) marine heat-ﬂow data

gradients from BHT and DST data are ~31 °C/

cess of petroleum exploration as petroleum

collected by means of gravity-probe measure-

km and ~38 °C/km, respectively.

cal ’cratonic’ values on the Kola Peninsula.

and Drilling Stem Test (DST) data also shows

Imaging deep structures at the surface

BHT and DST data from the western Barents Sea (www.npd.no). Well locations are given in the map.

Heat flow along the central Barents Sea transect.

It is well known that even corrected BHT

“Academician Kurchatov”. The proﬁle location

are, in general, biased towards lower values, so

is in line with the Kola superdeep borehole

that the ~38 °C/km value is our best estimate. In

SG-3 located in the Pechenga Trough.

Themal conductivity Thermal conductivity for shallow sediments in

the absence of more detailed data on the ther-

The main task of the thermal ﬁeld investiga-

the Barents Sea varies on average from 1.04 to

mal conductivity of the sediments encountered

tion along the geotraverse was to investigate

1.55 W/m•K, and correlates well with bathym-

in the wells, only a crude estimate of the heat

the heat ﬂow on the shelf. The objectives were

etry. For example, in the Murmansk and Ry-

ﬂow can be made. However, considering that

further to measure the nature of the heat ﬂow

bachi Banks, thermal conductivity is increased

the sedimentary pile of the SW Barents Sea

at shallow depth conditions, and to estimate

and reaches 1.04-1.42 W/m•K. The zone of max-

contains mostly shale-dominated deposits, we

the background heat ﬂow with and without the

imum thermal conductivity occurs on the Mur-

can infer that the bulk thermal conductivity is

inﬂuence of deep sea-bottom currents.

mansk Bank (the ﬁrst metre of sediments).

generally low. Assuming a bulk conductivity in

In the presence of near-bottom currents, de-

Thermal conductivity gradually smoothes

the reasonable range from 1.4 to 1.8 W/m•K and

termination of heat ﬂow using standard equip-

out at depth and averages 1.17 W/m•K. The

an average thermal gradient of ~38 °C/km, our

ment is almost impossible. Heat-ﬂow values

Samoilov Trench is characterised by a ther-

heat-ﬂow estimation derived from DST data

close to a deep (background) value are record-

mal conductivity reduction to 0.88 W/m•K.

ranges from ~53 to ~68 mW/m and remains in

ed only near Franz Josef Land. The mean heat-

Thermal conductivity of the sediments at this

good agreement with IKU determinations.

ﬂow value, according to 4 observation stations

station increases gradually with depth and

along the proﬁle, amounts to 54 mW/m and re-

reaches 1.26 W/m•K at a depth of 3 m. There

ﬂects the Palaeozoic age of crust consolidation

is a clear correlation between thermal conduc-

in the given region. Estimated heat-ﬂow data

tivity and sea-bottom topography, where a low

are constrained by heat-ﬂow measurements in

topographic relief results in a reduction of the

the Grumantskaya well on Spitsbergen. This

thermal conductivity.

Geothermal state of the Eastern Barents Sea Geothermal studies on the Eastern Barents Sea

well has been drilled to about 3200 m depth,

In general, the distribution of thermal con-

shelf started in the 1970s. At ﬁrst, probe meas-

and shows heat-ﬂow values in the order of 52

ductivity on the shelf is more complex than in

urements were carried out with the maximum

± 8 mW/m2.

the oceanic domain. There is also a strong corre-

sounding borer penetrating the sediments

In the south, in the area of the SG-3 well, the

lation between thermal conductivity and lithol-

down to a depth of 2 metres. Results of these

heat ﬂow amounts to 40 ± 4 mW/m2. Although

ogy. The mean thermal conductivity, 1.05-1.09

measurements were not adequate, since near-

scattered, the determined heat-ﬂow values pro-

W/m•K, along the Rybachi Peninsula – Franz

bottom temperature variations had a distort-

vide a preliminary picture of the possible back-

Josef Land section is higher than the recorded

ing eﬀect. In the 1980s, heat-ﬂow values were

ground heat-ﬂow values of the Barents Sea.

value in the deep ocean, 0.84-1.04 W/m•K.

determined in 67 boreholes; each borehole was

In the Eastern Barents Sea, the interval of

located in the vicinity of a Deep Seismic Sound-

possible oil generation and oil accumulation

ing (DSS) proﬁle.

can be found at depths between 4 and 6.5 km.

In 1976, geothermal gradients (GG) were

The temperature during oil formation at these

measured along the central Barents Sea

depths reached 110 -140° C and has remained

transect, and the thermal conductivity of sedi-

almost unchanged up to the present day.

Generally, the uncertainty of thermal conductivity measurements is 3-5%.

ments was studied on board the research vessel

Imaging deep structures at the surface

Chapter 3 Photo: stock.Xchng

From rift basins to mega-basins

Top basement The term ‘top basement’ describes the horizon

accuracy of the depth-to-basement estimates

mentary sequences are found in basins, such

at which the sedimentary load is separated

from the aeromagnetic data is of the order of

as the Nordkapp Basin, where sediments have

from the crystalline bedrock, and it therefore

+/- 1 km for the deepest parts of the basins, but

accumulated since the Devonian and crystal-

also represents the base of the basins. Typically,

can be better where seismic data are used as

line basement is found at a depth of about 8

sedimentary rocks have weak magnetisation,

a constraint. Depending on the methods and

km. Generally, the thickness of the successions

whereas the underlying bedrock commonly has

databases used, diﬀerent studies may result in

is about 6 km in the platform units and less over

a stronger magnetisation. Due to this contrast,

diﬀerent estimates of the basement depth.

basement highs where the youngest sedimen-

the transition from sediments to basement

In the Barents Sea region as a whole, the

tary layers are often missing. In the eastern Bar-

causes a distinctive set of magnetic anomalies

top basement usually lies deeper than 10 km

ents Sea, basins were ﬁlled during three main

that can be used to estimate the depth to the

and large diﬀerences can be observed between

periods, each of which is represented by the

basement. In the Barents Sea, estimates of the

the western and eastern parts. In the western

deposited sedimentary rocks. The lowermost

top basement depth are based mainly on the

Barents Sea, the top basement has a depth of

sedimentary rocks correspond to the Caledoni-

interpretation of aeromagnetic maps and com-

up to 14 km and reﬂects a series of narrow ba-

an stage of regional development and can be up

bined with interpretation of reﬂectors found

sins, whereas in the eastern Barents Sea, the

to 500 Myr old. These deformed rocks are fol-

in shallow- and deep-seismic lines. These pre-

top basement occurat up to 20 km depth and

lowed by Devonian deposits that are overlain

existing studies focus on either the western or

reﬂects the presence of two, broad, mega-scale

by Carboniferous-Lower Permian strata, prob-

the eastern Barents Sea or have only limited

basins, the North and South Barents basins.

ably belonging to the Early Hercynian stage of

resolution along the transition between the two

The basement map combines two of the recent

development. Constant seismic velocities (5.2-

areas, partly due to the disputed political border

compilations and is best constrained along

5.5 km/s) show the homogeneous composition

between Russia and Norway.

available, wide-angle, seismic lines.

and thickness of this second layer along almost

For the southwestern part of the Barents

Considering a water depth of about 400

the entire proﬁle crossing the Eastern Barents

Sea, this horizon is interpreted at a high reso-

m all over the Barents Sea, the basement map

Sea basins. The third and uppermost sedimen-

lution (5 km x 5 km) from aeromagnetic depth-

also indicates the sedimentary thickness, an

tary succession formed during the Late Permi-

to-source estimates combined with a variety of

important parameter for petroleum resources.

an, Triassic, Jurassic and Early Cretaceous time.

industrial shallow- and deep-seismic lines. The

In the western Barents Sea, the thickest sedi-

Legend

-10

-6 -4 Landmass

-14

-4 -6

Depth to Basement (km)

-4 -4 -2

-6

-8

-10

-4

-6

-6 -8

-14

-8

-8 -8 -10 -8

-8 -8

-4 -6

-6

-8 -6

-10

-4

-16

-10 -8

-2

-208 -1 -164 -1 -120 -1 -2

From rift basins to mega-basins

-6 -8 -8 -4

-8 -6

Depth-to-basement in the Barents Sea compiled after Skilbrei et al. (1991/1995) for the western part and Gramberg et al. (2001) for the eastern part.

Crustal thickness The crust is the outer solid shell of the Earth

sumed that the Moho indicates a density jump

eastern Barents Sea (35-37.5 km). The strongest

that sits on top of the more plastic mantle. The

and that the crust is ﬂoating on the mantle so

variations are related to the oﬀshore-onshore

thickness of the crust varies depending on

that the relief is compensated at depth. In the

transition around Novaya Zemlya and the

whether it is of continental or oceanic origin.

Barents Sea, the gravity anomaly suggests only

mainland to the south where the Moho deep-

The oceanic crust is much thinner than the con-

small variations in the thickness of the crust

ens to more than 40 km.

tinental crust. Nevertheless, some oceanic ar-

throughout the area. A map of the crustal thick-

eas on Earth, such as the Barents Sea, are com-

ness calculated from gravity is shown below.

From simple models of crustal extension, the correlation between the top basement and

posed of stretched continental crust and have

Detailed knowledge of the thickness and de-

Moho geometry is such that deep basins are

an intermediate crustal thickness. These areas

formation history of the crust is a key to under-

underlain by thin crust (shallower Moho).

are usually found at the edges of continents and

standing the geological history of a region. The

This is a typical observation for rift basins,

are called continental shelves.

map shows the Moho boundary as deﬁned in

and comparisons between top basement and

The horizon that deﬁnes the boundary be-

the Barents50 model. This model has a lateral

Moho maps show that this observation is, in

tween the crust and mantle is called the Moho

resolution of 50 km and is mainly a seismic-

general, true for the western Barents Sea. How-

after the Croatian seismologist Andrija Mo-

velocity model of the crust in the Barents Sea.

ever, in the eastern Barents Sea such a correla-

horovicic. The Moho can be deﬁned in diﬀer-

The velocity model is based on 2D wide-angle

tion is not observed. To a large extent, the total

ent ways: chemically, petrologically, through

reﬂection and refraction seismic data, passive

crustal thickness appears to be unaﬀected by

seismic velocity changes, or by a density dis-

seismological stations and, to a limited extent,

the broad, deep basins, and other mechanisms

continuity. Typically, the density changes from

potential ﬁeld data. The seismic Moho of the

have to be considered to explain the crus-

around 2800-3000 kg/m3 at the base of the crust

Barents50 compilation is generally ﬂat over

tal structure underlying the North and South Barents Sea basins.

to 3200-3400 kg/m in the upper mantle. Thus,

large parts of the Barents Sea region. From the

the Moho is associated with a large density con-

continent-ocean-boundary in the west to No-

trast and produces the main signal in regional

vaya Zemlya (east), the Moho depth is on aver-

gravity anomalies. The gravity anomaly can be

age 35 km, while in the western Barents Sea the

used to calculate the crustal thickness if it is as-

depth (32.5-35 km) is slightly less than in the

! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !!! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! !! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! !! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! !! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! !! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! !

! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! !!

! ! ! ! ! !

Seismic Profiles of the Barents50 Model (after Ritzmann et al. 2007)

-4 -3 0 8 -3 6 -3 4 -3 2 -3 0 -2 8 -2 6 -2 4 -2 2 >20

! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! !

A. The isostatic Moho depth reflects the isostatic compensation for loading by topography, bathymetry and sedimentary rocks. The reduced loading due to low-density sedimentary rocks leads to a shallower Moho than observed on seismic profiles. B. Moho map of the Barents Sea derived from seismic data (dotted lines show regional seismic transects) by Ritzmann et al. (2007).

From rift basins to mega-basins

Isostasy: compensation of sedimentary inﬁll Isostasy describes the equilibrium between

a geological scale, isostasy can be observed

of lithosphere reaches the state of isostasy, it is

the Earth’s lithosphere (the upper solid shell)

where the Earth’s strong lithosphere exerts

said to be in isostatic equilibrium.

and asthenosphere (weak and plastic layer be-

stress on the weaker asthenosphere, which

There are three main models that are used to

low the lithosphere) such that the continental

over geological time ﬂows laterally such that

explain this isostatic equilibrium. Based on these

plates ‘ﬂoat’, similarly to icebergs or rafts. The

the load of the lithosphere is accommodated by

ideal assumptions, isostatic corrections are ap-

extent of the plate above and below a certain

height adjustments. Such heights can be seen as

plied to gravity data to remove the gravity eﬀect

level depends on its thickness and density.

mountains or islands, or may also be expressed

of masses in the deep crust or mantle that iso-

In the simplest case, isostasy is related to the

by sedimentary basins. Isostasy is invoked to

statically compensate for surface loads. Here, we

Archimedes principle of buoyancy - when an

explain how diﬀerent topographic heights can

used the Airy-Heiskanen model to calculate the

object is immersed, an amount of water equal

exist at the Earth’s surface. When a certain area

isostatic gravity anomalies.

in mass to that of the object is displaced. On

Isostasy Local concepts of isostasy propose that the Earth is in hydrostatic equilibrium at depth, requiring topography to be compensated either by lateral variations in crustal thickness (Airy-Heiskanen isostasy) or crustal density (Pratt isostasy). a) In the Airy-Heiskanen model (Airy 1855, Heiskanen 1931), the compensation is accomplished by crustal roots under the high topography that intrude into the higher-density material of the mantle to provide buoyancy for the high elevations. Over oceans, the situation is reversed. The Airy isostatic correction assumes that the Moho is like a scaled mirror image of the smoothed topography, that the density contrast across the Moho is constant, and that the thickness of the crust at the shoreline is a known constant. Scaling is determined by the density contrast and by the fact that the mass deficiency at depth must equal the mass excess of the topography for the topography to be in isostatic equilibrium. b) Isostatic corrections can also be made for the Pratt model (Pratt 1855), in which the average densities of the crust and upper mantle vary laterally above a fixed compensation depth. c) Regional isostasy after Vening Meinesz (1931): In this model, the crust acts as an elastic plate and its inherent rigidity spreads the support for topographic loads over a broader region.

a) Airy

c) Vening Meinesz

b) Pratt

hn ς k = const.

HN TN

sea level

ςK

HA ς0 ςn ςM

ςM > ςK

ςM TN (ς M − ς K ) = hn ς k

ς 0 H A = ς n (H A + hn )

REFERENCES: Airy, G.B. (1855) On the computation of the effect of the attraction of mountain-masses, as disturbing the apparent astronomical latitude of stations of geodetic surveys. Phil. Trans. R. Soc., 145, 101-104. Heiskanen, W.A. (1931) Isostatic tables for the reduction of gravimetric observations calculated on the basis of Airy’s hypothesis. Bull. Géodésique, 30, 110-129.

From rift basins to mega-basins

Pratt, J.H. (1855) On the attraction of the Himalaya mountains, and of the elevated regions beyond them, upon the plumb line in India: Phil. Trans. R. Soc., 145, 53-100. Vening Meinesz, F.A. (1931) Une nouvelle methode pour la réduction isostatique régionale de l’intensité de la pesanteur. Bulletin Géodésique, 29, 33-51.

Isostatic Residual Map To constrain the density distribution within

of 35-37 km, as evident from regional seismic

of the Barents Sea area and can be used for

the sedimentary rocks, one can use a density-

proﬁles and compilations in the eastern Bar-

the interpretation of the geological evolution

depth relationship that represents sediment

ents Sea, is substantially greater than required

of the Barents Sea. In the case of the Barents

compaction with depth. Due to this compac-

to isostatically balance the deep basins here

Sea, the isostatic residual map is calculated by

tion, the upper sedimentary layers are mostly

(>19 km). The crust-mantle boundary that rep-

considering the gravity eﬀect of the sedimen-

responsible for mass deﬁciency relative to

resents isostatic equilibrium should be 8 km

tary rocks and their compensation at the base

the surroundings, whereas sedimentary rocks

shallower than the observed seismic Moho.

of the crust. Due to the shallow isostatic Moho,

at greater depths have similar densities com-

This may indicate that there is a compensat-

the isostatic residual generally shows negative

pared to the surrounding bedrock. The result-

ing surplus mass in the lower crust and/or up-

anomalies. This indicates that the area is over-

ing isostatic Moho is very diﬀerent from the

per mantle. Comparison with the magnetic and

compensated and the crustal base should be

seismic Moho. For example, the isostatic Moho

gravity anomaly maps shows diﬀerent anoma-

deeper. This is in agreement with the observed

is 8 km shallower than the seismic Moho in the

ly patterns. This suggests that the crust is het-

seismic Moho. In addition, one can interpret

eastern Barents Sea. Possible explanations for

erogeneous and hence that part of the isostatic

more localised areas of isostatic anomalies (e.g.

the diﬀerence are: (1) the sediment model den-

compensation might be due to the change in

the continental edge and the transition from

sities are too low, (2) there is a compensating

crustal properties over the Barents Sea Region.

land to sea). Over most of the Barents Sea the

surplus mass in the lower crust and/or the up-

The eastern Barents Sea basins fall into

isostatic residuals are relatively similar, but an

per mantle, or (3) the seismic Moho is too deep.

a class of so-called intra-cratonic basins and,

area in the western Barents Sea, north of 74ºN,

A possible explanation for the isostatic re-

for these basins, isostatic compensation is

shows large deviations. However, information

sponse of the mega-scale basins of the eastern

commonly achieved by high-density bodies

on top basement is sparse here and the isostatic

Barents Sea involves lateral density changes in

in the lower crust or upper mantle. The iso-

residual map may indicate a change in the tec-

the lithospheric mantle. The crustal thickness

static residual map reﬂects the isostatic state

tonic framework of the Barents Sea.

-2 00 -1 75 -1 50 -1 25 -1 00 -7 5 -5 0 -2 5

Isostatic residual map of the Barents Sea.

mGal

From rift basins to mega-basins

Chapter 4

Continents in motion The Barents Sea in a plate tectonic and structural framework

The geology of the Barents Sea area can be explained by a complex combination of large-scale processes controlled by plate movements and varying climatic and depositional conditions during hundreds of millions years of cont-inental drift. In a platetectonic perspective, the main tectonic phases setting the geological framework of the Barents Shelf are the Timanian, Caledonian and Uralian orogenies, the proto-Atlantic rifting in the west, the opening of the Euramerican Basin in the north, and the subsequent break-up and opening of the northern North Atlantic Ocean along the western margin of the shelf. Superimposed on these major phases are several minor tectonic events which locally led to large variations in depositional regimes and palaeogeographic scenarios.

Midterhuken, Bellsund, Svalbard. Photo: Arvid NĂ¸ttvedt

Gernigon

-NGU-GEO

BASE-200

Admiral High

Kara Sea 0 2 4 6 8

Storfjorden Fan

Bjørnøya Fan

Central Barents High

Bjørnøya

Western Barents Sea

Nordkapp Basin

Norway Cenozoic indif. Neogene Paleogene Cretaceous Jurassic Mid-Upper Triassic

Lower Triassic-Permian Upper Carboniferous-Permian Paleozoic undiff. Upper Devonian-Carboniferous Devonian Pre-Devonian

10 12 14

lya

South Barents Basin

Eastern Barents Sea

Depth (km)

Norwegian Greenland Sea

Storbanken

Edgeøya

ich ov

North Barents Basin

m Ze aya Nov

Kong Karl Platform

Svalbard d Ri

Franz Josef Land

cean Arctic O

Yermack Plateau

Knip

Elevation - Bathymetry (m)

1000 800 600 400 200 0 -2 0 0 -4 0 0 -6 0 0 -8 0 0 -1 0 0 0 -1 2 0 0 -1 4 0 0 -1 6 0 0 -1 8 0 0 -2 0 0 0 -2 2 0 0 -2 4 0 0 -2 6 0 0 -2 8 0 0 -3 0 0 0 -3 2 0 0 -3 4 0 0 -3 6 0 0 -3 8 0 0 -4 0 0 0

la-

nin

clin

Timan-Pechora 500 km

Sill intrusion

Three-dimensional bathymetry of the Barents Sea continental shelf and regional geological profile

t the present day, the large-scale

Svalbard archipelagos. This deﬁnes one of the

to the subsurface in Svalbard and surround-

structure of the Barents Shelf can

largest areas of continental shelf on Earth with

ing platforms. In Franz Josef Land, outcrops of

be roughly subdivided into two ma-

water depths usually lower than 500 m. The

Mesozoic sediments and volcanic rocks shows

jor and diﬀerent geological provinces, sepa-

Barents Sea has been tectonically aﬀected by

a development similar to that on the northeast-

rated by a huge monoclinal structure located

major continental collisions and a complex

ern Svalbard Platform, where sill intrusions

in the centre of the study area. The geology of

rifting history leading ultimately to continen-

are observed. The volcanic episodes in both

the eastern province was mainly inﬂuenced

tal break-up and formation of the Norwegian-

areas are closely connected with the opening

by the complex tectonic histories of Novaya

Greenland Sea and Arctic Ocean to the north,

of the Arctic Ocean during the Late Mesozoic.

Zemlya and the Timan-Pechora Basin and by

clearly highlighted by a deeper bathymetry.

The western shelf bordering the continent-

the Uralian Orogeny. The geology of the west-

The most signiﬁcant sedimentary basins, in

ocean transition is characterised by the eﬀects

ern province was mostly controlled by major,

terms of both thickness and areal extent, lie

of Cenozoic tectonics and sedimentation asso-

post-Caledonian rifting phases as well as by

in the Russian part of the Barents Sea, west of

ciated with the Spitsbergen Orogen and subse-

later rifting episodes which led to continental

Novaya Zemlya. Both the North and South Bar-

quent continental break-up. Large thicknesses

break-up along the northwestern margin of the

ents Sea basins formed in the foredeep zone

of Cenozoic sediments were deposited in this

Eurasian plate.

to the Novaya Zemlya tectonic belt directly in

area both before and after the onset of drifting

The Barents Sea is a region bracketed by

the northwestern prolongation of the onshore

in the Oligocene. The sediments were derived

the eastern border of the Norwegian-Greenland

Pechora Basin. The sag basins terminate in the

from a signiﬁcant uplift and erosion of the Bar-

Sea, the north Norwegian and Russian coasts,

West Barents Sea, where sedimentary rocks, lo-

ents Shelf immediately to the east.

and the Novaya Zemlya, Franz Josef Land and

cally aﬀected by Cretaceous magmatism, rise

Continents in motion

Early Tertiary (60Ma)

Late Cretaceous (80 Ma)

Early Cretaceous (130 Ma)

Late Jurassic (150 Ma)

Late Triassic (220 Ma)

Late Permian (250 Ma)

Early Permian

Late Devonian

Late Silurian

Global reconstructions and North Atlantic paleography from Early Tertiary to Late Silurian. Illustrations from BATLAS (2002).

Continents in motion

Timanian and Caledonian orogenies and Late Devonian - Early Carboniferous times Western Barents Sea

evidently extends for a distance of nearly 2000

The tectonic history and basement evolution

km throughout Norway, and is extensively ex-

of the Barents Sea have set a premise for the

posed in northwest Finnmark and Troms. Cale-

structural framework of this Arctic Ocean. It

donian inﬂuences are seen in the N-S structural

is quite complex, and still debatable locally,

grain of the western Barents margin and Sval-

but the main outlines are relatively well estab-

bard, and the NE-SW grain of the southwest-

lished up to the time of the Palaeoproterozoic

ern Barents Sea and Finnmark. Old, inherited

Svecofennian orogeny, setting the scene for the

structures usually appear to be the ﬁrst-order

stable Russian-European platform adjacent to

crustal parameters that control the rift or basin

the Archaean Fennoscandian Shield. The latest

architecture of the West Barents Sea area. This

Neo-Proterozoic Timanide Orogen developed

is clearly highlighted by potential ﬁeld data,

as an accreted and superimposed fold-and-

which are clearly inﬂuenced by the basement

thrust belt in the eastern part of the Barents

conﬁguration throughout the entire Barents

Sea region during Vendian (Ediacaran) time.

Sea.

The main NW-SE, Timanian orogenic trends

Following the Caledonian orogeny, Devo-

are exempliﬁed by the Kanin-Timan Ridge and

nian to Early Carboniferous time was charac-

the Kola-Kanin Monocline southwest of the

terised by exhumation and extensive erosion

Timan-Pechora and Barents provinces. In the

of the hinterlands, leading to accumulation of

Timan–Kanin–Pechora-Varanger region, major

Old Red Sandstone deposits in the western

NW–SE structural trends also reﬂect a reacti-

part of the Barents Sea area. The denudation

vation of known Palaeoproterozoic and older

was accompanied by post-Caledonian rifting,

lineaments during the Meso- to Neoproterozo-

and many of the evolving early rift basins de-

ic (Mid to Late Riphean) rifting and extension

veloped along Caledonian structural features.

that characterised the northeastern margin of proto-Baltica. In the West Barents Sea area, the basement

During Early Palaeozoic time, the tectonic set-

in the Scandinavian Caledonides. The Caledo-

tings in the eastern Barents Sea and Kara Sea

nian Orogeny culminated approximately 400

areas were diﬀerent. Pericratonic extension

million years ago, and resulted in a consolida-

and passive margin development character-

tion of the Laurentian and Baltican plates into

ized the Kara Sea areas.

the Laurasian continent, following the closure

From late Middle to early Late Devonian

of the Iapetus Ocean, a major seaway that oc-

time, the transition from a stable, passive,

cupied a position more or less similar to the

continental margin to an active margin was

modern northeast Atlantic. The Caledonian

completed. This is documented by the pro-

Orogeny in Norway traditionally has been

gressive westward subduction of the Uralian

regarded as having originated from two ma-

oceanic crust in the southeastern part of the

jor tectonic phases: 1) an early, Finnmarkian

Barents Shelf. This process was accompanied

phase (Late Cambrian to Early Ordovician)

by pericratonic extension in the Timan-Pecho-

and 2) a later Scandian phase (Mid Silurian to

ra basin, which possibly extended farther in

Early Devonian). Recent geochronological data

areas of the South and North Barents Sea. By

from Finnmark, however, have revealed a more

Early Frasnian times, this rifting episode was

complex history partly involving Sveconorwe-

accompanied by basaltic eruptions in the No-

gian and younger Neoproterozoic deformation

vaya Zemlya and Timan-Pechora regions.

events.

Eastern Barents Sea

history mainly corresponds to that recorded

From Late Devonian through Early Carbon-

The Caledonian Orogeny is well document-

iferous times, a back-arc, marginal deep-water

ed on Svalbard where N-S-striking bedrock

basin, formed near Novaya Zemlya and the

is exposed along most of the northern and

adjacent part of the Kara Shelf. During this pe-

western coasts of Spitsbergen and Nordaust-

riod, a shallow carbonate platform developed

landet. Furthermore, the Caledonide Orogen

in the central part of the East Barents Region.

Continents in motion

Main structural elements of the Barents Sea. The map highlights 1) the main onshore and offshore geological units of the Barents Sea and surroundings modfied after the 1:5 million scale bedrock geology map of the Arctic, 2) the main structural features of the Barents Sea after the Norwegian Petroleum Directorate, and 3) the approximate depth to the base Cretaceous reflectors.

Continents in motion

Uralian Orogeny and subsequent Mesozoic times

Eastern Barents Sea

likely resulted from thrusting of the island arc

Sea area was terminated by the development

The progressive closure of the Uralian Ocean in

above the Barents Plate.

of epicontinental basins from the beginning of

the Carboniferous initiated a continental colli-

The development of an unconformity at the

sion between Baltica and Kazakhstan, leading

Permian-Triassic boundary coincides with ma-

to the formation of the Ural Mountains south

jor volcanic eruptions and the formation of a

of Pay-Khoy. The Uralian Orogeny can be sub-

large igneous province, and an associated phase

Western Barents Sea

divided into an Early Carboniferous to Late

of rifting in West Siberia. The timing of the ac-

In contrast to the east, regional extension domi-

Permian collisional phase and a Late Permian-

companying uplift and erosion in the southeast

nated the western Barents Sea area during the

Triassic orogenic phase.

has been constrained by the presence of clasts

Carboniferous. This episode is part of the long-

Early Jurassic time, which has continued up to the present day.

During Late Carboniferous through Permi-

of Palaeozoic rocks in Lower Triassic sediments.

lived Palaeozoic-Mesozoic pre-opening rifting

an times, the ﬁnal closure of the Uralian Ocean

Closely linked to the tectonic events that

episodes that developed in the North Atlantic.

took place as a result of an inferred collision of

occurred in the Urals, continental deposition

On seismic data, the rift structures are locally

the Yamal-Gydan Plate and an island arc bor-

characterised the Timan-Pechora region dur-

recognised below the extensive Upper Carbon-

dering the Novaya Zemlya marginal basin. This

ing the entire Triassic period. The formation

iferous to Lower Permian, carbonate platform

assumption is supported by seismic data that

of the Uralide Orogen was markedly episodic,

deposits which cover large parts of the Barents

shows evidence of folding within the eastern

however, and this led to the development of

Shelf. In the Late Palaeozoic, thick successions

part of the South Kara Basin during Carbonifer-

major unconformities, each overlain by coarse

of evaporates were locally deposited locally in

ous and Permian time. Along the eastern edge

clastic material that originated from the Ural

the diﬀerent graben systems that developed in

of the present-day Barents Sea, the sedimentary

mountains. The presence of braided river facies

the southwestern parts of the shelf (i.e., Ottar

succession on the carbonate shelf was gradually

adjacent to the Timan Ridge suggests that this

Basin, Tromsø Basin, Bjørnøya Basin, Nord-

folded and thrusted. This caused a progressive

uplifted area was a major sediment source.

kapp Basin).

ﬁlling of the Novaya Zemlya foredeep with ter-

The Triassic geological evolution of the

A major, Early Triassic, rift episode is also

rigenous material derived from the growing

North and South Barents Sea Basin was also

recorded in the Barents Sea, and is also recog-

Kara thrust belt. Seismic data also suggest the

strongly inﬂuenced by tectonic events that took

nised in many parts of the Arctic and North

existence of intermontane troughs and depres-

place in the adjacent fold belt. An important

Atlantic regions.

sions in the distal parts of the orogen. On No-

unconformity at the Permian-Triassic bound-

Mid-Late Triassic time was generally char-

vaya Zemlya, deep-water cherts and turbidites

ary, evident from well logs and seismic data,

acterised by post-rift thermal subsidence in the

accumulated and numerous reefs formed along

characterises this major event. Very rapid, fore-

North Atlantic and Arctic basins. In the West-

the margins of the sediment-starved, deep-wa-

land basin subsidence in areas adjacent to the

ern Barents Sea, the Lower to Middle Triassic

ter troughs.

Urals is witnessed by the accumulation of up to

succession comprises transgressive-regressive

During the Early to Late Permian transition,

6 km of sediment in the east, and much of this

cycles of marine, deltaic and continental clas-

regional seaways developed around Baltica and

is thought to have been deposited in Early to

tic sediments, and a number of discrete minor

the western shelf margins, and progressively

Middle Triassic times.

tectonic events can be recognised. To the west

opened a connection between the Boreal Realm,

Several models have been proposed for the

of the Hammerfest Basin, a latest Permian to

the Central European Zechstein Basin and the

westward displacement of Novaya Zemlya,

Early Triassic rifting event is assumed to have

proto-North Atlantic rift system. In the cen-

some of which have suggested convergence

occurred, which may have continued until Late

tral and western parts of the Barents Shelf, the

estimates of as much as 500-700 km. Such esti-

Anisian to Early Ladinian time. During that

emergent Uralide Orogen and the connection

mates require a scenario where Novaya Zemlya

period, salt movements are interpreted to have

with the Tethys Ocean led to a drastic change in

was ﬁrst involved in the Uralian Orogeny (and

begun in Early Scythian time and continued

depositional regime from warm-water platform

forming a near-linear continuation of the Ural-

into later Triassic time in the Nordkapp Basin.

carbonates to cold- and deeper-water, ﬁne clas-

ide Belt), and then subsequently thrusted into

On Svalbard itself, minor fault activity also oc-

tics and silica-rich spiculites.

the Barents Sea to reach its more westerly posi-

curred during the Triassic period occurred. Low-

From Late Permian to Early Triassic time,

tion. In more recent models, it is assumed that

er to Middle Triassic strata reﬂect repeated del-

the ﬁnal phase of the Uralian Orogeny eventu-

Novaya Zemlya was already in a more westerly

taic progradations from a westerly Laurentian

ally led to closure of the Novaya Zemlya mar-

position by Late Triassic-Early Jurassic times

source, which decreased in importance through

ginal basin. In the beginning of the Late Per-

and may not have been aligned with Taimyr and

time. Triassic tectonism in the Bjørnøya area

mian, subsidence continued, accompanied by

the Uralide Belt. In this model, the westward

most likely comprised a series of uplifts. This

turbiditic sedimentation in the East Barents

movement occurred in the Late Triassic-Early

interpretation is supported by a slight angular

Sea Basin. During this time, a remnant shallow-

Jurassic and was limited in magnitude to 100-

unconformity between the Triassic strata and

water basin continued to cover a vast area in

200 km.

underlying Upper Permian carbonates, and the

the east. The development of the Pay-Khoy–No-

This Late Permian-Triassic tectonostrati-

vaya Zemlya fold structures in the Triassic most

graphic event in the eastern part of the Barents

Continents in motion

fact that the succession is highly discontinuous.

Pacific Ocean

Chukotka

Sv er dr up

Ural Ocean

Sa km ari an ba ck Barentsia -ar ? cb as in Barents

Siberian Platform

m Lo

ba sin

Kara Sea Barents Sea

Timon Pechora

Sea

Greenland Greenland

Laurentia

Late Silurian

Moscow Platform

Baltica

Caledonides

L. Jurassic Ural Ocean

Siberia

Proto Arctic Ocean

Sv er dr up

? Sak mar ian b ackarc b asin

Chukotka

Siberian Platform

m Lo

ba sin

Kara Sea

? Barents Sea

Timan Pechora

Barents Sea

Inuit ian F B.

Timan Pechora

Greenland

Moscow Platform

Baltica North America

Greenland

L.Devonian-E. Carboniferous

Baltica

E. Cretaceous Sv er dr up

Pacific Ocean Kazakhstan

Chukotka

Arctic shelf

Timan Pechora

Barents Sea

Greenland

Baltica

Kara Sea Barents Sea

Kazakhstan

Timan Pechora

Greenland Moscow Platform

Baltica

L. Cretaceous Sv er Arctic shelf dr up ba sin

Pacific Ocean

ba sin

North America

Carboniferous

Siberian Platform

m Lo

Ural FB. Moscow Platform

Laurentia

Kazakhstan

Siberian Platform

Sv er dr up Kazakhstan

Barents Sea

a Timan l fo ld Pechora be

Laurentia-Greenland

Barents Sea

Baltica

Kara Sea

ba sin

Moscow Platform

Timan Pechora

Moscow Platform

Greenland Baltica

Late Permian

E. Tertiary Siberian Platform

Arctic shelf Sv er dr up ba sin

Kara Sea

Barents Sea

Greenland Timan Pechora

Barents Sea

Baltica

Mid.-Late Trias

NorwegianGreenland Sea

Moscow Platform

Timan Pechora Moscow Platform

Baltica

L. Tertiary

@Gernigon_02/06

Pacific Ocean

Major fold belts

Emergent areas

Sallow to deep marine

volcanic provinces

Compression

Minor deformation front

Coastal to sallow marine

Oceanic domain

Extension

Sand influx

Schematic cartoon of the geodynamic evolution of the North Atlantic and Arctic regions (after Ziegler 1988).

Continents in motion

Stable platforms and pre-breakup basins From Middle to Late Triassic time, a signiﬁcant

Major transgressions in the early Late

change occurred in the palaeogeography of

Jurassic and at the very end of the Jurassic

the Barents Shelf area. This change coincided

period ﬂooded the entire Barents Shelf and

with the initiation of a progressive uplift of the

shallow-shelf to deep-marine sedimentation

northern, eastern and southern Barents Sea

prevailed over large areas. During Early Creta-

regions. The evidence for this event includes

ceous time, the northern Barents Sea area was

a signiﬁcant westward thickening of the Car-

subsequently uplifted and large amounts of

nian strata, a thickening which is interpreted

sediment were shed from the rising continen-

as representing clastic inﬂux from the Fenno-

tal areas in the northeast into deeply subsiding

scandian Shield and possibly also partly from

basins in the west. This Early Cretaceous uplift

a westerly Laurentian source. By Late Carnian

was associated with a major volcanic event that

time, much of the western Barents Shelf, in-

occurred on Franz Josef Land, Kong Karls Land

cluding the Hammerfest Basin, was covered

and adjacent oﬀshore areas. The Cretaceous

by widespread alluvial plains, and coastal and

magmatic event possibly coincides with the

shelf-break settings.

onset of sill intrusions in the southern Barents

Renewed tectonic activity occurred towards

Sea, which could provide evidence for a wide-

the end of Late Triassic time in both the North

spread and major volcanic activity in the Bar-

Atlantic and the Arctic regions, and continued

ents Sea and Arctic regions. This tectonomag-

into earliest Jurassic time. In the Canadian and

matic event along the northern rim coincides

Alaskan Arctic, uplift and erosion is recorded,

with the onset of break-up prior to the opening

but on Svalbard and the Barents Shelf fault

of the Arctic Ocean.

activity, presumably linked with extension in

Along the southwestern Barents Shelf, suc-

the North Atlantic region to the south, seems

cessive rifting episodes during the Cretaceous

to have been more signiﬁcant. Simultaneously

led to rapid subsidence and the development of

with these North Atlantic and western Arctic

major deep basins such as the Harstad, Trom-

events, compression and uplift, generated by

sø, Bjørnøya and Sørvestsnaget basins. These

the Uralian Orogeny, still controlled the sedi-

events represent a northern extension of simi-

mentation in the Eastern Barents and Timan-

lar rifting phases described from the Mid-Nor-

Pechora areas. By Late Triassic time, uplift and

wegian margin. Aptian rifting is evident in sev-

erosion in the eastern Barents Sea-Kara Sea

eral places on the shelf and a major Cretaceous

region led to extensive, westward, coastal pro-

thinning of the crust aﬀected the Bjørnøya and

gradation and the development of continental

Sørvestnaget basins. Uplift continued towards

and coastal-plain environments over major

the north, and by Late Cretaceous time large

parts of the Barents Sea area, whilst marine

parts of the Barents Shelf were uplifted. The

environments were restricted to the western-

Late Cretaceous to Palaeocene rifting phase

most parts. During Early and Middle Jurassic

between Norway and Greenland was progres-

times, continental and marine deposition was

sively taken up by strike-slip movements and

widespread in the East Barents Basin, which is

deformation within the De Geer Zone, leading

generally interpreted as a ﬂexural response of

to the formation of pull-apart basins in the

the Uralian collision and orogeny. As a result,

westernmost parts of the Barents Sea.

increasingly subsiding epicontinental marine basins developed on Novaya Zemlya. In the western Barents Sea, the northern progradation of the Middle Jurassic to Early Cretaceous Atlantic rifting aﬀected particularly the western margin of the Barents Shelf and triggered the development of a marine connection across the Barents Shelf. In the northern areas, tectonic activity appears to be related to extension in the Amerasia Basin, a precursory event of the opening of the Arctic Ocean.

Continents in motion

3D interpretative cartoon of the Nordkapp Basin and surrounding platforms compared with potential field data.

The Nordkapp Basin is one of the most characteristic graben features in the West Barents Sea. The Nordkapp Basin is essentially a deep Palaeozoic and Triassic depocentre significantly affected during active and passive salt diapirism. The salt was deposited in the Late Carboniferousâ&#x20AC;&#x201C;Early Permian and has been locally remobilised several times. Upper Palaeozoic and Mesozoic sediments filled in the basin and were uplifted by salt diapirism in the Early/Middle Triassic, Late Jurassic, Late Cretaceous and Tertiary periods. Subsequently, regional uplift and erosion in the Early Tertiary and extensive glacial erosion in the Late Pliocene/Pleistocene removed up to 1000 m of the Mesozoic and Cenozoic strata and left the succession that remained strongly tilted and truncated around the salt diapirs, and covered by only a thin sheet of glacial sediments. Structuring associated with these diapirs has created a number of interesting plays which are currently being evaluated. This area has been recently covered by high-resolution aeromagnetic data, providing an efficient and promising tool for qualitatively and quantitatively constraining basement features, sedimentary contacts, faults and salt-related features.

Continents in motion

55 60

Eocene

Paleocene

Campanian

Late

Cretaceous

90 95 100 105 110 115 120

Cenomanian Albian

Aptian Barremian

150 155 160 165 170

uplift and Ural Orogen an phase)

175 180 185

Hauterivian Barremian Barriasian Thithonian

Late

Middle

Thoarcian

Early

195

205

Late

210

Triassic

215 220 225 230 235

Carnian

Anisian

245

Early

250 255

Lopingian

Permian

265 270 275 280 285

Guadalupian

Carboniferous

320 325

335 340

370 375 380 385 390 395 400

Paleozoic

345

Late Penns.

Gzhelian Kasimovian

Mid. Penn.

Moscovian

Early Penn

Bashkirian

Late Miss.

Mid. Miss.

430 435 440

n along Khoy

Frasnian Givetian

Middle

Early

470 475 480

Telychian

Llandovey

Late

Middle

500 505

Svalbard (â&#x20AC;?Laurentiaâ&#x20AC;?) 84Â°-335Â°E

Cambrian

495

C e3 A l11

Ap3 B a rr

B 5 a rr

1H a 5

Ti 5

O x6

Aeronian

Furogian Series 3

Thanetian Selandian Danian

Ypresian

Neogene

90 95

BREAKUP EURAMERICAN BASIN regional transgression

minor faulting

115 120

140 145 150 155

several transgressive pulses

160 165 170 175 180

Barremian Barriasian

N o2

Middle

C a r3

Lad 3

215 220

terrigenous coast environementrifting (N. Atlantic, 4O l

e n d -P e rm

225

minor faulting

Wu c h1

Barents Sea (â&#x20AC;?Balticaâ&#x20AC;?) 74Â°-40Â°E

A rt1

organic buildups evaporites

285

regional transgression

Boreal and Tethys oceans disconnected

Hung ar-N BalatR Koca e-N

Vis1 To u 2r

330

graben formation

widespread intracratonic rifting

SmN

1 GN1 K a rat mysh

ia n N

365 370

Fam 1

375 380 385

F ra s 1

390 395

G iv 1

400

E if1 E m s1

P ra g 2 P ra g 1

collision Baltica-Greenland turbidite succession (Caledonia Orogen) H om 1 S

Te ly2 ei

Te ly1 n A 1 e

H irn 1 1

Sandbian

5 th 1

Darriwilian

D a rr1

Dapingian

progressive closure of the Iapetus major plate reorganisation

Tre m2 Tre m1

425 430 435 440

Mid. Penn.

Moscovian

Early Penn

Bashkirian

Late Miss.

Serpukhovian

Mid. Miss.

Visean

460 465 470 475 480

495

505

Iapetus formation

Svalbard (â&#x20AC;?Laurentiaâ&#x20AC;?) 84Â°-335Â°E

Chronostratigraphic time scale from Gradstein et al. (2004)

2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4

6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

Yp 1 0 T 5h

Tournaisian

Givetian

M a1

C am 8 C am 5 Sa3

Rhae t-N? E24 E23 E22 E21 E20 E19 E18 E17 E16 E15 E14 E13 E12 E 11 E10 E9 E8 E7 E6 E5 E4 E3 E2 E1

C e3

A l11

Eifeilian

Neva d-N1

Hung ar-N

Ap6

B a rr

1H a 5

Va3 Be7 Ti 5

O x6

Sp R 1 SmN

ia n N

Furogian

N o2

Series 3

transgressive phases regional transgression

renewed uplift and erosion of Ural orogen

C a r3

Lad 3

4O l

e n d -P e rm

Marginal

Pechora Basin Central

rifting (N. Atlantic, Arctic, W. Siberia)

Siberian trapps

C ap 1

Ro ad 1 Kung2 Kung1

A rt1

A ss1

minor faulting

Rapid subsidence

rapid subsidence

clastic influx subsidence SW Barents Sea

faultinghalokinesis

tilt and erosion of the Loppa High faultinghalokinesis

regional stable carbonate transgression Platform

stable carbonate platform

carbonate platform organic buildups Boreal and Tethys evaporites oceans disconnected

G zh 2 G zh 1 K a s1

major magmatic event

Late Cenozoic regional uplift

Kara Sea

Novaya-Zemlya North Central

Marginal

Late Cenozoic regional uplift

Central

Marginal

several transgressive pulse

several transgressive pulses

regional transgression

major extension and uplift of the margin

regional transgression

B a sh 1

graben formation

Vis2

major clastic propagation from S-SE

To u 2r

Fluvial-lacustrine lacustrine to shallow environements marine prevail environements

marine environement prevail

To u 1r

Fam 1

renewed uplift and erosion of Ural Orogen (Cimmerian phase)

rifting

orogeny faulting alluvial and deltaic plain

alluvial and deltaic plain major flooding event

terrigenous coast environement

avalanche sedimentation

carbonate platform faulting and uplift alluvial plain with lakes

graben formation sand influx from West

Vis1

regional uplift

regional uplift, residual soil

stable carbonate platform

Bsac s h 2

several transgressive pulses

pelagic biogenic sediments

transition deltaicopen marine environement

folding

carbonate coast environment

F ra s 1

G iv 1 E if1

Te ly2 ei

Te ly1 n A 1 e

H irn 1 1

Katian Sandbian

5 th 1 D a rr1

Dapingian

post-orogenic collapse collision Baltica-Greenland (Caledonia Orogen)

rifting

Ellesmerian orogen inversion and folding

progressive closure of the Iapetus

carbonate platform

major plate reorganisation extension along Pay Khoy

Tre m2 Tre m1

Stage 10 Stage 9

Marginal

Regional transgression

karst formation

M o

H om 1

Tremadocian

Novaya-Zemlya Centre Central

Marginal

minor fault reactivation

Loppa High formed faultinghalokinesis depocenter by L. Trias

Uralide orogeny

humid climate affects

Wu c h1

Darriwilian

Paibian Guzhangian Drumian Stage 5

Cretaceous volcanism

2P I

Foian

Early

Central

8P I

Lo ch 1

Aeronian

rapid subsidence rapid subsidence SWofBarents pulse rifting toSea the W.

faultinghalokinesis faultinghalokinesis

A a2

E m s1

Ludfordian Gorstian Homerian Sheinwoodian

Marginal

uplift to the North

impacttransgressive of asteroid several pulses

B a t3

P ra g 1

Hirnantian

Middle

episodic rifting episodes

P ra g 2

Pragian

rapid subsidence after cessation of spreading

MjĂ¸lnir

1 GN1

K a rat mysh

compression along BjĂ¸rnĂ¸yrenna F.C

minor faulting

B 5 a rr

Parac r-N Sp R 2 Sp R 2

Rhuddanian

Late

delta propagation from N-NW

Ap3

Fluvial-lacustrine environements prevail

Telychian

Llandovey

Verkhoyansk orogeny East Siberia

(lo w e

Lochkovian

Prodoli Ludlow Wendlock

shear margin development

uplift-erosion in Arctic areas

4A l

stable carbonate platform

BalatR Koca e-N

South Barents Basin

Franz-Josef Land Central

Marginal

L. PalaeoceneE. Eocene uplift rifting episode

L. PalaeoceneE. Eocene uplift

Eurekan Orogeny

N. Atlantic rifting leading to breakup

7A l

karst formation

Marg ar-N

Finnmark Platform-Kola Kanin Central

Marginal

Tu4

tilt and erosion of the Loppa High

Emsian

Early

Central

Spitzbergen compression

BREAKUP N. ATLANTIC

widespread intracratonic sand influx from West rifting

Frasnian

Middle

transtensional and transpressive regimes along the Western Barents shelf

S1e l

clastic influx

n ii-R

485 490

M M M M M M M M M M M M M M M M

r) Curio

Late

450

500 No D aat

Gzhelian Kasimovian

445

455

Wordian Roadian

Famennian

415 420

Capitanian

Late Penns.

410

Ellesmerian orogen

W Wuchiapingian

Cisuralian

Early Miss.

405

collapse

Lo ch 1

Stage 10 Stage 9

345

360

To u 1r

post-orogenic inversion and folding

Tremadocian

340

355

Parac r-N Sp R 2 Sp R 2

Sp R 1

335

350

Olenekian Induan Changhsingian

Asselian

305

Late Cenozoic regional uplift

Marginal

BjĂ¸rnĂ¸ya-Loppa High Nordkapp Basin Marginal

regional uplift

Rapid subsidence sedimentation

Artinskian

300

325

carbonate coast environment

M25

Kungurian

295

320

B a sh 1

M 24B

Sakmarkian

315

Guadalupian

290

310

M o

Neva d-N1

Lopingian

280

Bsac s h 2

(lo w e

255

L 4u

M 25A

Ladinian

Early

250

270

G zh 2 G zh 1 K a s1

Vis2

245

Central

C h 1 /R 4 u

Loppa High formed depocenter by L. Trias

Anisian

265

folding

Norian

Middle

275

faulting and uplift carbonate platform

Sinemurian

Carnian

260

C ap 1 Ro ad 1 Kung2 Kung1

A ss1

235 240

Siberian trapps

Arctic, W. Siberia)

230

Central Svalbard Bjarmeland Platform Marginal Late Cenozoic

transgressive phases

Hettangian Rhaetian

Late

Central

C h41 /A q

faultinghalokinesis

Calllovian Bathonian Bajoncian Aalenian Thoarcian

210

Uralide orogeny

humid climate affects sedimentation

Kimmerigian

Plienbachian

Early

205

orogeny faulting

M"-1"r (C34 n) M0r M1 M3 M5 M6 M7 M8 M9 M10 M10N M1 1 M11 A M12 M12A M13 M14 M15 M16 M17 M18 M19 M20 M21 M22 M22A M23 M24 M24A

Oxfordian

200

renewed uplift and erosion of Ural orogen

Thithonian

Late

Late Cenozoic regional uplift

pulse of rifting to the W.BREAKUP EURAMERICAN BASIN

Barremian

195

2P I

S e4r / To r1

GEODYNAMIC EVENTS

rapid subsidence

Aptian

Hauterivian

190

LG M

M 2 e

compression along BjĂ¸rnĂ¸yrenna F.C Albian

130 135

C1 C2 C2A C3 C3A C3B C4 C4A C5 C5A C5AA C5AB C5AC C5AD C5B C5C C5D C5E C6A C6AA C6B C6C C7 C7A C8 C9 C10 C1 1 C12 C13 C15 C16 C17 C18 C19 C20 C21 C22 C23 C24 C25 C26 C27 C28 C29 C30 C31 C32 C33 C34 M"-3"r set (C34 n) M"-2"r set (C34

rifting episode

Santonian Coniacian Turonian

Cenomanian

Early

125

185

Katian

Paibian Guzhangian Drumian Stage 5

delta propagation from N-NW

A a2

6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

Marg ar-N

Paleocene

Late

110

8P I

M25

Rhae t-N? E24 E23 E22 E21 E20 E19 E18 E17 E16 E15 E14 E13 E12 E 11 E10 E9 E8 E7 E6 E5 E4 E3 E2 E1

Lutetian

Campanian

105

episodic rifting episodes

Eocene

Maastrichtian

100

B a t3

M 24B

2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4

Priabonian Bartonian

Va3 Be7

Oligocene

shear margin development

Verkhoyansk orogeny East Siberia

Ap6

Marginal Miocene

several Eurekan transgressive pulse

uplift-erosion in Arctic areas

4A l

Spitzbergen compression

Orogeny

N. Atlantic rifting leading to breakup

7A l

M"-1"r (C34 n) M0r M1 M3 M5 M6 M7 M8 M9 M10 M10N M1 1 M11 A M12 M12A M13 M14 M15 M16 M17 M18 M19 M20 M21 M22 M22A M23 M24 M24A

M M M M M M M M M M M M M M M M

BREAKUP N. ATLANTIC

Tu4

Foian

Early

485 490

Sa3

Pragian

Ludfordian Gorstian Homerian Sheinwoodian

Hirnantian

Ordovician

465

Eifeilian

Rhuddanian

450

460

C am 5

Lochkovian

Prodoli Ludlow Wendlock

445

455

Tournaisian

Emsian

Silurian

425

Visean

Famennian

415

e platform

M a1 C am 8

n ii-R

410

420

Serpukhovian

Late

405

T 5h S1e l

r) Curio

Early Miss.

Devonian

315

365

Wordian Roadian

Asselian

330

Capitanian

Sakmarkian

310

360

W Wuchiapingian

Cisuralian

300

355

Changhsingian

Artinskian

295

350

Olenekian Induan

Kungurian

290

305

L 4u

Yp 1 0

M 25A

Ladinian

260

pelagic biogenic sediments

Norian

Middle

240

nsgressive ses

Sinemurian Hettangian Rhaetian

200

Barents Sea (â&#x20AC;?Balticaâ&#x20AC;?) 74Â°-40Â°E

Calllovian Bathonian Bajoncian Aalenian

Plienbachian

190

alluvial and deltaic plain

Kimmerigian Oxfordian

Jurassic

145

Mesozoic

130

140

Santonian Coniacian Turonian

Early

125

135

Thanetian Selandian Danian Maastrichtian

nsgression

Lutetian Ypresian

L. Pleist. M. Pleist. E. Pleist. Gelazian Piacenzian Zanclean Messinian Tortonian Serravalian Langhian Burdigalian Aquitenian Chatian Rupelian

No D aat

Iapetus formation

Chronostratigraphic time scale from Gradstein et al. (2004)

turbidite succession

@Gernigon-GEOBASE_NGU

transtensional and transpressive regimes along the Western Barents shelf

Paleogene

Palaeo-latitude after Torsvik et al.

C h41 /A q C h 1 /R 4 u

Central 15

PLiocene

Cretaceous

Priabonian Bartonian

Late Cenozoic regional uplift

Marginal

Jurassic

Oligocene

Central

Holocene PLeistocene

Triassic

S e4r / To r1

Late Cenozoic regional uplift

TRcycles

BjĂ¸rnĂ¸ya-Loppa High

Q u a te rn a ry

Permian

M 2 e

CHRONOSTRATIGRAPHY 0

Carboniferous

LG M

Ă&#x203A;N

Devonian

Palaeo-latitude after Torsvik et al.

Miocene

L. Pleist. M. Pleist. E. Pleist. Gelazian Piacenzian Zanclean Messinian Tortonian Serravalian Langhian Burdigalian Aquitenian Chatian Rupelian

Ă&#x203A;N

Silurian

Cenozoic

Holocene PLeistocene

PLiocene

Equator

Ordovician

Q u a te rn a ry

Ă&#x203A;S

Cenozoic

Ă&#x203A;S

Central Svalbard

GEODYNAMIC EVENTS

Mesozoic

Ă&#x203A;N

Marginal

Paleozoic

Ă&#x203A;N

TRcycles

Central

Cambrian

Equator

Late Cenozoic regional uplift

Marginal

CHRONOSTRATIGRAPHY Neogene

Ă&#x203A;S

Central

Paleogene

Ă&#x203A;S

Kara Sea

Novaya-Zemlya North

Late Cenozoic regional uplift

Marginal

@Gernigon-GEOBASE_NGU

Novaya-Zemlya Centre Central

Lithostratigraphic correlations of the Barents Sea. The columns represent an average lithology and tectonic history of each area. An overview of the existing, accepted, lithostratigraphic units on Svalbard and the western Barents Shelf is presented in the Lithostratigraphic Lexicon of Svalbard (Ed. W.K. Dallmann, Norwegian Polar Institute 1999). For information of the Russian lithostratigraphic units the reader should consult the reference list at the end of this book.

Continents in motion

Lithostratigraphic correlations of the Barents Sea. The columns represent an average lithology and tectonic history of each area.

conglomerates

fluvial-red beds

sands-sandstones

biohermes

silts-silstone

cherty sediments

shale-claystone

coal

limestones

source rocks

dolomite-dolostones

uplift

evaporites

major trangression

volcanic rocks

major regression

Continents in motion

conglomerates

fluvial-red beds

sands-sandstones

biohermes

silts-silstone

cherty sediments

shale-claystone

coal

limestones

source rocks

dolomite-dolostones

uplift

evaporites

major trangression

volcanic rocks

major regression

An overview of the existing, accepted, lithostratigraphic units on Svalbard and the western Barents Shelf is presented in the Lithostratigraphic Lexicon of Svalbard (Ed. W.K. Dallmann, Norwegian Polar Institute 1999). For information of the Russian lithostratigraphic units the reader should consult the reference list at the end of this book.

20 25 30 35 40 45 50 55 60

Neogene

Cenozoic

Holocene PLeistocene

PLiocene

Miocene

Oligocene

Paleogene

Q u a te rn a ry

Paleocene

Campanian

Late

Cretaceous

90 95 100 105 110 115 120

Cenomanian Albian

Aptian Barremian

160 165 170 175 180 185

Hauterivian Barremian Barriasian Thithonian

Late

Middle

Thoarcian

Early

195

205

Late

210

Triassic

215 220 225 230 235

Carnian Ladinian Anisian

245

Early

250 255

Lopingian

260

Permian

265 270 275 280 285

Guadalupian

Carboniferous

320 325 330 335 340 345

395 400

Late Penns.

Gzhelian Kasimovian

Mid. Penn.

Moscovian

Early Penn

Bashkirian

Late Miss.

Serpukhovian

Mid. Miss.

Visean

Early Miss.

Tournaisian

Famennian

Late

Devonian

315

390

Frasnian Givetian

Middle

Early

410

435 440

Silurian

430

Prodoli Ludlow Wendlock

Hirnantian

470 475 480

Ordovician

465

Late

Middle

500

Geologic Timescale (From Gradstein et al. 2004).

505

Darriwilian Dapingian Foian

Early

Cambrian

495

Katian Sandbian

485 490

Aeronian Rhuddanian

450

460

Ludfordian Gorstian Homerian Sheinwoodian Telychian

Llandovey

445

455

Pragian Lochkovian

415

425

Eifeilian Emsian

405

420

Wordian Roadian

Asselian

310

385

Capitanian

Sakmarkian

305

380

W Wuchiapingian

Artinskian

300

375

Changhsingian

Cisuralian

295

370

Olenekian Induan

Kungurian

290

365

Norian

Middle

240

360

Sinemurian Hettangian Rhaetian

200

355

Calllovian Bathonian Bajoncian Aalenian

Plienbachian

190

350

Kimmerigian Oxfordian

Jurassic

155

Mesozoic

130

150

Santonian Coniacian Turonian

Early

125

145

Thanetian Selandian Danian Maastrichtian

140

Lutetian Ypresian

135

L. Pleist. M. Pleist. E. Pleist. Gelazian Piacenzian Zanclean Messinian Tortonian Serravalian Langhian Burdigalian Aquitenian Chatian Rupelian

Priabonian Bartonian

Eocene

Paleozoic

Lithostratigraphic correlations of the Barents Sea. The columns represent an average lithology and tectonic history of each area.

Furogian Series 3

Tremadocian Stage 10 Stage 9 Paibian Guzhangian Drumian Stage 5

Western Barents Sea A

300-

Mag (nT)

Tilt derivative

MagTF

2001000-

MagTF HP-75

-10080-

Bouguer

40200-20-

Bouguer HP-75

-40-60-

7318/5-1

Stappen High

Bjørnøya Basin

7321/7-1

Svalis Dome

-5Depth (km)

-150

Cenozoic undiff. Neogene Paleogene Upper Cretaceous Lower Cretaceous Jurassic 50

Bjarmeland Platform

7228/2-1

? ??

deep Paleozoic basin ?

Mid-Upper Triassic Mid. Triassic Lower Triassic II Lower Triassic I - undiff. Permian Salt (Carboniferous) 100

Nordkapp Basin

Cenozoic intrusions

-10-

7324/10-1

L. Gernigon-GEOBASE-NGU-2009

Gravity (mGal)

60-

? deep Paleozoic basin 150

200

250

300

350

400

450

500

550

(km)

North Atlantic break-up

The Paleocene-Eocene transition marks the

margin of the Barents Shelf. The crustal short-

marine slope to basinal successions are pre-

continental break-up of the North Atlantic mar-

ening was concomitant with major extension

served along the western margin. In the Vest-

gins and opening of the Norwegian-Greenland

between Norway and Greenland and is esti-

bakken Volcanic Province there is evidence of

Sea at around 55-54 Ma. This time interval is

mated to have been around 30 km.

breakup-related sill intrusions. Over the west-

also characterised by a major magmatic event,

Progressively, the continental strike-slip

ern Barents Shelf, there is are major uncon-

as witnessed by massive basaltic traps and the

system, active from the Paleocene to the

formities between the Paleogene to Miocene

formation of volcanic rifted margins which

Eocene, was followed by a passive shear-mar-

strata and overlying glacial deposits marking

have been identiﬁed from the Irish margin

gin development, leading to break-up from

the onset of the Northern Hemisphere glacia-

up to the Lofoten and NE Greenland shelves.

Early Oligocene time. Since Oligocene times,

tions in the Late Pliocene. During the Pliocene-

Towards the north, the break-up development

separation of the Barents Shelf and Greenland/

Pleistocene the entire Barents Shelf was eroded

along the sheared margin of western Barents

North America has continued, leading to the

and large amounts of sediment were shed into

Sea was younger, locally magmatic (e.g., Vesta-

opening of the Fram Straight and establishing

towards the shelf margin accumulating as huge

bakken volcanic province) and comparatively

a North Atlantic-Arctic marine connection in

wedges of shelf-margin, slope and basinal ma-

complex.

the Miocene.

rine origin (Bjørnøya and Storfjorden fans).

Prior to the opening, a transpressive event

Lower Tertiary deposits are virtually absent

occurred between Svalbard and the northern

on the eastern and central Barents Shelf but

Continents in motion

Eastern Barents Sea C

300-

Tilt derivative

Mag (nT)

200-

MagTF HP-75

1000-

MagTF

-100-

80-

Bouguer HP-75

Gravity (mGal)

6040200-

Bouguer

-20-40-60-

NW Nordkapp Basin

Central Barents High

Novaya Zemlya

South Barents Basin

? Cretaceous (?) intrusions ?

? deep Paleozoic basin

asin zoic b Paleo p e e d

deep Paleozoic basin

-10-

L. Gernigon-GEOBASE-NGU-2009

Depth (km)

-5-

100 km -150

100

150

200

250

300

350

400

450

500

550

600

650

Regional geological profiles and potential field signature across the Barents Sea. The locations of the profiles A-B and C-D are shown on page 43.

The Barents Sea consists of complex structural features including platform areas, basement highs, graben features and large sag-basins. The most significant sedimentary basins, in terms of both thickness and areal extent, lie in the East Barents Sea located immediately west of Novaya Zemlya. This province was affected by a major phase of collision between the Laurasian continent and Western Siberia, which culminated in latest Permian-earliest Triassic time. Novaya Zemlya marks the suture zone of this closure, which could be younger (Triassic-Jurassic) in that specific region. Huge basins, such as in the South Barents Sea, formed in the foredeep zone to the Novaya Zemlya fold belt, and acted as major catchment areas for sediments shed from the front of the belt in Late Palaeozoic-Mesozoic times. Mesozoic sediments up to 10 km in thickness are present in these basins. Particularly significant, is the presence and thickness of Triassic deposits, locally 6–8 km, that accumulated in a series of deltas prograding westward from Novaya Zemlya.The Triassic formations are particularly affected by numerous sill intrusions, possibly linked to the Early Cretaceous volcanism recorded on Franz Josef Land and Svalbard. This volcanism occurred during the rifting stage of the opening of the Canada Basin. To some extent, the deeper nature of the South Barents Sea basin is poorly constrained. Palaeozoic sediments are probably present locally in the South Barents Sea and could represent a prolongation of the rift system well documented onshore in the Timan-Pechora Basin. The West Barents Sea represents a different structural style, affected by several episodes of rifting. The West Barents Sea is a large Permo-Triassic platform affected by major graben-type basins, as illustrated in this section. The main grabens were probably initiated by Late Palaeozoic extension, contained significant evaporite deposits of probable Late Carboniferous-Early Permian age and were major sites of Triassic deposition. The movements of Palaeozoic salt most likely began in the Early Triassic and since then the diapirs observed in the Svalis Dome and Nordkapp Basin areas have undergone several phases of development during the Mesozoic and Cenozoic. Early Triassic extension initiated salt-tectonic activity in the Nordkapp Basin and diapirs grew passively until mid-Triassic times by maintaining their crest at or near the sea floor, while sediment accumulated in adjacent salt-withdrawal basins. The tectonic features of the basins observed today were finally shaped by subsequent Late Jurassic-Early Cretaceous reactivation and strong Cenozoic uplift. Between the Stappen High and the Savlis Dome, the Bjørnøya Basin underwent further extension leading to rapid subsidence in Cretaceous times, before the onset of the shear-margin development illustrated by the Vestbakken volcanic province. All these structural elements and salt-related features are reflected both in the gravity and in the high-resolution magnetic signatures.

Continents in motion

(km)

Chapter 5

Pteraspistoppen, Liefdefjorden on Spitsbergen; a thick succession of Lochkovian sandstones of the Ben Nevis Formation. Photo Winfried Dallmann

Lochkovian Caledonian mountains in the west, and lowlands and shallow-marine basins in the east

Russkaya Gavan, Novaya Zemlya; stromatolites in the Lower Devonian Veselogorskaya Formation. Photo: : VSEGEI

In Lochkovian time the western and northern parts of the Barents Sea-Kara Sea region were part of the northern extension of the Old Red Continent formed by collision of Laurentia and Baltica. Here, continental clastic sediments accumulated in intra-cratonic and foreland basins delineated by major extensional faulting. The eastern Barents Sea-Kara Sea region was covered by an extensive shallow-water basin with predominantly carbonate sedimentation.

Pteraspistoppen, Liefdefjorden on Spitsbergen; Wulffberget conglomerate, lower part of the Red Bay Group. Photo: Winfried Dallmann

n the Early Devonian, the Caledonian

grabens are ﬁlled with terrestrial alluvial-lacus-

beds here contain intercalations of near-shore

collisional orogeny culminated and Lau-

trine conglomerates, sandstones, siltstones and

marine dolomites, and in places also limestones.

rentia and Baltica were merged into the

mudstones of the Red Bay Group, containing

On Severnaya Zemlya, Lochkovian strata are

abundant ﬁsh and plant fossils.

represented by variegated sandstones, silt-

so-called Old Red Continent. The formation and subsequent denudation of the Caledonian

In the eastern Barents-Kara Sea region, the

stones, mudstones with interbeds of marls, do-

mountains controlled the sedimentation pat-

Lochkovian palaeogeography was quite diﬀer-

lomites, and limestones bearing ostracods and

tern in the western and northern Barents Sea

ent and more varied. In the Early Lochkovian,

ﬁsh faunas. The marine and transitional facies

region. Here, rapid exhumation and extensive

this area was covered by an extensive shallow-

in the west grade into deeper-water facies to

erosion of the hinterland high grade metamor-

water basin with predominantly carbonate

the east, pointing towards a proximity to sedi-

phic complexes resulted in deposition of con-

sedimentation.

In this shallow sea, stroma-

ment source areas in the west. The thickness of

tinental siliciclastic sediments in intra-cratonic

tolitic dolomites, biochemical limestones, co-

strata and the number of carbonate inter-beds

and foreland basins which were delimited by

quina beds, rare marls and detrital limestones

increases eastwards.

major extensional faulting along Caledonian

accumulated. During Late Lochkovian through

In the southern part of the Barents Sea, and

and Svalbardian lineaments.

Emsian time the situation changed, and a de-

in the southern and middle parts of Novaya

Even though the main Caledonian tecton-

pression with black shale sedimentation devel-

Zemlya, a shallow-water pericratonic marine

ism took place in the Silurian, plutonism on

oped in the east. At the same time, carbonate

basin existed. In this basin, a succession of

the Svalbard archipelago continued into Early

platform coral-stromatoporoid build-ups origi-

limestones, dolomites and anhydrites, mud-

Devonian time, as evidenced by migmatites

nated in the south and southeast along the mar-

stones and siltstones accumulated. The thick-

in northwest Spitsbergen and granite plutons

gin of the basin.

ness of Lochkovian deposits varies from 60 m

throughout the central and eastern parts of the island dated to the earliest Devonian.

Russkaya Gavan, Novaya Zemlya; colonies of corals in limestones of the Lower Devonian Retovskaya Formation. Photo: VSEGEI

Lower Devonian clastic sediments are doc-

in the western part of the Pechora Shelf to 700

umented from the Medvezhij and Severo-Vos-

m in the eastern ares of the shelf and on Novaya

Lower Devonian deposits show a limited

tochnaya Zemlya islands and Franz Josef Land.

Zemlya.

distribution in the western part of the Barents-

Lower Devonian terrestrial red beds are also

By the end of Lochkovian time, a depression

Kara Region, and are found only in a few grabens

known from northern Novaya Zemlya and Sev-

appeared in the central part of Novaya Zemlya.

and sub-basins that formed as a result of the

ernaya Zemlya. The sediments were most likely

In this depression, organic rich carbonaceous

Late Caledonian tectonic movements. On Sval-

shed from the Caledonian orogen in the west.

shales (total organic carbon up to 5%) and clay-

bard, Lochkovian sediments are restricted to

On Novaya Zemlya, Lower Devonian deposits

ey limestones with numerous dacrioconarids

half-grabens in northern Spitsbergen (Andrée

extend along the shore from Gribov Bay in the

were deposited. During the subsequent Pragi-

Land, Dickson Land), but this pattern of molas-

south (Mitushinskaya Formation) to Russkaya

an and Emsian stages the depression expanded

se deposition most likely extended eastwards

Gavan’ Bay in the north (Kanjonnaya, Jermo-

and its western margin moved farther west on

and southwards across much of the Barents

laevskaya and Veselogorskaya formations). In

the Barents Shelf.

Shelf. On northern Svalbard, the outcropping

contrast to the sections on Svalbard, the red

Lochkovian

Lochkovian 416.0—411.2 Ma

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

78°0'0"N

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

76°0'0"N

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=

* * * * * * * * * *

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

74°0'0"N

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *= * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * ** ** ** ** * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * ** ** ** ** * *

* * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=

* * * * * * ** ** ** ** * *

= =

* =* =

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * * * * * * * *** ** ** * * * * * * * ** ** * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=*

* * * * * * * * * * * * *** ** ** * * * * * * * ** ** * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =* * = * =

* * * * * * * * * ** * * * * * * * * * ** ** * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=

* * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * ** * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * * * * * * * * * * * * * * ** * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=

* * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

= =

* * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

* * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *=

* * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

= =

* * * * * * * * * * *

70°0'0"N

= =

=* =

= =

* * * * * * * * * * * * *** ** ** * * * * * * * ** ** * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

= =

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

= =

* *= * =* *= = = = = = = = = = = = = = = = =

* * * * * * ** ** ** ** * *

* * * * * * * * * * * * * * * * * * * *

= =

* * * * * * * * * *

= =

* * * * * * * * * *

72°0'0"N

= =

* *= * =* *= = = = = = = = = = = = = = = = =

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * =* *= * =*

= =

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *= * =* *= =

* * * * * * * * * * * ** * * * * ** * * * * ** * * * * ** * * * * ** * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * *

= =

= * = = = = = = = =

68°0'0"N

* * * * * * * * * * * ** * * * * ** * * * * ** * * * * ** * * * * ** * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * *

30°0'0"E

* * * * * * * * * *

40°0'0"E

50°0'0"E

Highlands / Denudation area

Sandstone

Lacustrine/Fluvial plain/basin

Shallow-water shelf

Alluvial

Shelf

Coast

Deep-water shelf

* * * *

Sandstone, Siltstone, Clay Shale

= =

Cherty shales

Limestone / Dolomite Build-ups

Lochkovian

Chapter 6

Upper Devonian sedimentary rocks at Reindyrsflya, northern Spitsbergen. Photo: Jan StenlĂ¸kk

Frasnian Active rifting and expansion of the marine basin in the east

Kilen, central Dickson Land, Spitsbergen. Frasnian-Famennian multi-coloured sandstones and conglomerates below the Svalbardian angular unconformity (above: Moscovian and younger, light-coloured sediments). Photo: Winfried Dallmann

In Late Givetian to Early Frasnian time an active phase of intra- and pericratonic rifting took place in the eastern part of the Barents-Kara region. In the west, denudation and erosion of the Caledonian orogen continued, and the extensive land areas over most of the western Barents Sea were gradually peneplaned. In the east, the pre-existing marine basin expanded during the Late Devonian.

Coral boundstone in the lower part of a thick 12 m thick biostrome in the Voronin Formation in the vicinity to the Russian Harbour, northwest Novaya Zemlya. Photo: Geir Birger Larssen

tructures in the SW Barents Shelf are

Josef Land. Petrochemical data from Devonian

generally orientated NE-SW, following

maﬁc igneous rocks on Novaya Zemlya suggest

Caledonian trends. In Finnmark, the

a close similarity to oceanic basalts.

ESE-WNW-trending Trollfjorden - Komagelva

In the eastern part of the Barents Sea region,

deposited in deltaic and estuary settings, was

Fault Zone was reactivated in an extensional

a marine shelf and more distal, deeper marine

gradually replaced by lagoonal and littoral clay-

phase in Late Devonian to earliest Carbonifer-

conditions prevailed in the Late Devonian, the

ey and clayey-carbonate sediments.

ous time. To the north, contemporaneous rift-

deepest parts of the basin lying east of Novaya

In eastern Barents Sea region, there are lat-

ing initiated the formation of the Nordkapp

Zemlya. Moving from west to east, a prograd-

eral environmental changes from shallow-water

Basin.

ing deltaic system developed, with deposition

carbonate shelf settings towards the intra-shelf

In Frasnian time, land areas still occupied

of shallow marine sediments. During Early Fras-

depressions. In the depressions, domanic-type

almost the whole territory of the western Bar-

nian time, a marked marine ﬂooding signiﬁ-

deposits represented by bituminous lime-

ents Sea. In the intracratonic basins, extensive

cantly enlarged the areal extent of the marine

stones, calcareous mudstones and cherts ac-

continental siliciclastic deposition continued.

basins.

cumulated. The deep-marine black shales of

This is well documented on Svalbard where Old

A shallow-marine carbonate platform oc-

Red Sandstones of the Andrée Land Group are

cupied the south, west and north of Novaya

(TOC) content of 3-6%, and constitute a proliﬁc

preserved in half-grabens in central and north-

Zemlya and the greater part of the Timan-Pecho-

hydrocarbon source rock in the Timan-Pechora

ern Spitsbergen. It is likely that these Frasnian

ra area. South and west of Novaya Zemlya, la-

area. In the eastern part of the Timan-Pechora

rift basins were wider than the Early Devonian

goonal environments existed. During Frasnian

area, deposition of the domanic-type sediments

molasse basins. On Spitsbergen, the Frasnian

time, Lower and Middle Devonian strata were

continued throughout the Late Devonian.

sediments of the Mimerdalen Formation were

eroded in the southern part of Novaya Zemlya,

In the east, thick carbonate build-ups were

deposited in a lacustrine environment and con-

whereas Silurian to Middle Devonian strata

formed along the edges of the marine carbonate

tain common ﬁsh and plant remains.

was removed in the north. Shallow-marine sedi-

platform and on local elevated areas. They gen-

the domanic facies have a total organic carbon

From seismic and gravity data it appears

mentation was typical for the western-central

erally represented isolated bioherms, but reefs

that Late Devonian rift basins, similar to the

part of Novaya Zemlya. Here, the limestone

and barrier systems are also present. In the Late

half-grabens, were also developed oﬀ the coast

beds contain marine faunas and biostromes

Devonian, domanic deposits also accumulated

of Finnmark. Similar rift basins possibly exist-

built by rugose corals.

along the western coast of Novaya Zemlya in

ed farther to the north in the area of the western Barents Sea.

Vertical oriented limestones of the basal part of the Late Devonian Voronin Formation in the vicinity to the Russian Harbour, northwest Novaya Zemlya. Photo: Geir Birger Larssen

Numerous volcanoes formed a continuous

the outer shelf environments near the bound-

belt along the western coast of Novaya Zemlya,

ary to the deep-water basin. Organic-rich calcar-

In the eastern part of the Barents Sea, includ-

and separated a deep-water depression in the

eous shales, with intercalations of clayey and

ing the Novaya Zemlya and Timan-Pechora re-

eastern part of the island from a shallow-water

organogenic goniatite limestones, constitute

gion, Givetian to Early Frasnian tectonic move-

basin to the west. In this depression, there are

the main lithology of these strata. Some of the

ments were followed by a general subsidence

numerous basalt pillow-lava ﬂows with interca-

shales have TOC values up to approximately

of variable extent. In some places the fracturing

lation of siliceous shales.

6%. Thin, black, phosphate-bearing siliceous

of the continental crust led to intensive basaltic

In the Timan-Pechora area, the Lower Fras-

shales, commonly with abundant radiolarians,

eruptions, as documented on Novaya Zemlya,

nian succession records an increased trans-

were deposited in the inner part of the Novaya

possibly with some maﬁc magmatism on Franz

gression, and the succession of silts and sands

Zemlya marginal basin.

Frasnian

Frasnian 385.3—374.5 Ma

78°0'0"N 76°0'0"N

== == == == == == == == == == == == == == = = == == == == == == == == == == == == == == == = =

72°0'0"N

74°0'0"N

+ + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = ==+ ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == + + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == = + + + + + + + + +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == = ==+ ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = + +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == = ==+ ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == + + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = + + + + + + + + +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = ==+ ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = + +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == = =+ ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == + + + + + + + + + == + == + == + == + == + == + == + == == == == == == == = +== +== +== +== +== +== +== +== == == == == == == == + + + + + + + + + ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == == = ==+ ==+ ==+ ==+ ==+ ==+ ==+ ==+ == == == == == == ==

= =

== == == == == == == == == == == == == == = = == == == == == == == == == == == == == == == = = =

70°0'0"N

= =

68°0'0"N

= =

30°0'0"E

40°0'0"E

50°0'0"E

Highlands / Denudation areas

Shallow-water shelf

Lava

Limestone / Dolomite

Lacustrine / Fluvial

Shelf

Sandstone

Limestone

Marsh / Lacustrine

Deep-water shelf

Clay, sandstone, limestone

Marl

Alluvial

Deep basin

Cherty shales

Build-ups

= =

Frasnian

Chapter 7 The upper packstone-dominated part of the Ledyanogavan Formation at Gavan, northwest Novaya Zemlya. Photo: Geir Birger Larssen

Visean Extensive alluvial plains in the west and marine carbonate shelves and deep basins in the east

Lower Carboniferous deposits, with coals seams, at Pyramiden, Svalbard. Photo: Morten Smelror

In the Visean, the depositional conditions of the Barents Sea â&#x20AC;&#x201C; Kara Sea region varied considerably from continental environments in the west to marine carbonate shelves in the east. The climate was generally tropical and humid.

Sigillaria stem, Lemstrømfjellet, SW Ny-Friesland, Svalbard. Photo: Winfried Dallmann

Ledyanogavan Formation at northern Ledyanaya Gavan Bay, showing interbedded oolitic grainstones and green silt overlain by more thickly bedded oolitic grainstone. North East Novaya Zemlya. Photo: Geir Birger Larssen

Lower Carboniferous sandstone and coaly shale alternations, Cowanodden, Billefjorden, Svalbard. Photo: Winfried Dallmann

he general large-scale picture, with an

heterolithic marsh deposits contain coals and

a transition towards deposition of more ﬁne-

emergent continental regime in the

carbonaceous shales.

grained carbonates.

west and a broad marine carbonate

Towards the end of the Visean, activity along

Shallower-marine carbonate regimes exist-

shelf in the east, is the dominant feature of the

the lineaments ceased and erosion of the high-

ed northwest of Novaya Zemlya, over the east-

Visean. However, the post-Caledonian depo-

lands gradually led to the development sedi-

ern Barents Shelf, and in the western part of the

sitional regime gradually changed from intra-

mentary systems dominated by braided plains,

Timan-Pechora Region. In the shallow-marine

montane molasse environments to a landscape

building out eastwards into wide ﬂood-plains

environments, wackestones, packstones and

more dominated by ﬂuvial plains.

and coal-bearing marshes. The sedimentary

grainstones were deposited.

In the western parts of the Barents Shelf

systems of the central Barents Shelf, such as

The northernmost part of Novaya Zemlya

there was a complex system of highlands, al-

the Nordkapp Basin and Bjarmeland Platform,

appears to have been emerged at this time. This

luvial and ﬂuvial plains, marshes and pre-

were probably similar to those found on Spits-

is suggested by the tongue of shallow-marine

dominantly easterly prograding deltas, and the

bergen and Bjørnøya, but not subject to the

deposits trending eastwards across the north-

sedimentary systems were partly controlled by

same frequent strike-slip inversions. The ﬂu-

ern part of the island, where mudstones and

active horst-graben tectonics and basin forma-

vial plains and coal marshes graded eastwards

sandstones with oolitic iron ore dominate the

tion. The western margin of the Barents Shelf,

into broad delta plains towards the marine

stratigraphic record.

including western Spitsbergen and Bjørnøya,

realms of the eastern Barents Sea. Initial ﬂood-

The marine carbonate shelves which cov-

was located in a strike-slip transfer setting with

ing of the Finnmark Platform from the east is

ered the eastern Barents Sea, Kara Sea and Ti-

horst and graben development along N-S trend-

evident from thin Upper Visean carbonate beds

man-Pechora areas graded into continental en-

ing lineaments. Farther east, in the Nordkapp

(Blærerot Formation) recovered near the coast

vironments towards the west and northwest.

Basin, Bjarmeland Platform and surround-

oﬀ eastern Finnmark.

Westwards, the carbonate shelf passed into the

ing areas, the basin geometries were control-

In the east, various types of carbonate shelf

ﬂuvial and deltaic plains of the post-Caledonian

led by NE-SW trending lineaments associated

conditions existed. Relatively deep marine

continental landscape. Towards the northwest,

with transitional transform/extensional move-

carbonate deposition took place over most of

the shallow-marine carbonate environments

ments.

Novaya Zemlya and the western Kara Sea. In

passed into a coastal regime, and farther into

Subsidence along the lineaments and basin

the deep basin to the east, the Lower Visean

alluvial plains that covered Franz Josef Land.

margins was a typical feature of this Visean

deposits comprise black phosphate-bearing

In the southwest, the carbonate shelf margins

landscape, with alluvial systems grading later-

chert and siliceous shales, with radiolarians

terminated against the Fennoscandian Shield,

ally into ﬂuvial plains, lakes and marshes. The

and conodonts. Later in the Visean there was

which was emergent at the time.

Visean

Visean 345.3—326.4 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

30°0'0"E

40°0'0"E

50°0'0"E

Highlands / Denudation area

Shallow-water shelf

Sandstone

Limestone, sandstone

Marsh / Lacustrine

Shelf

Sandstone, siltstone, clay, coal

Limestone

Alluvial

Deep-water shelf

Shale

Pelagic limestone

Deep basin

Build-ups

Visean

Chapter 8 Cabiniferous and Lower Permian strata exposed at Cowanodden, Billefjorden, Svalbard. Photo: Morten Smelror

Moscovian Rising sea level and drier climate

Thinly to massive bedded, variably cherty limestones with textures ranging from grainstones to wackestones in the Efuglvika Member reflects the establishment of carbonate shallow shelf sedimentation. A phylloid algal reef in the upper layer in one of the closest cliffs. Efuglvika, South West BjĂ¸rnĂ¸ya. Photo: Geir Birger Larssen

At the onset of the Moscovian, the sea areas had expanded so that carbonate shelf conditions also reached into the western Barents Shelf. The climate had changed from tropical humid to sub-tropically arid and major evaporate deposits formed.

The 265 m high Fortet at Rudmosepynten, Billefjorden, Spitsbergen. Thick collapse breccias and important large-scale collapse structures are developed at this locality. Photo: Geir Birger Larssen

he northward drift of Pangaea during

The Hornsund fault zone was still active,

ditions existed. To the west, the Troms-Finnmark

the Carboniferous resulted in a climatic

shedding alluvial-fan and braided-plain clastic

Platform and Nordsel High were probably also

shift from tropical humid to semi-arid

deposits eastwards. Similarly, the Billefjorden

emerged at this time.

and arid throughout most of the Barents Sea and

fault zone was active, spreading debris eastwards

Shallow-water carbonate shelf environments

Kara regions in the Moscovian. Combined with

onto an adjacent narrow evaporite belt. Similar

occupied most the eastern Barents Shelf and the Ti-

an overall regional transgression, the climatic

facies are observed in the Landnøringsvika and

man-Pechora area. Oolitic limestones, calcareous

change had signiﬁcant eﬀects on the depositional

Kapp Kåre formations on Bjørnøya, and are also

sandstones, detrital wackestones and packstones

environments in the area. A major consequence

present on the Loppa High.

formed on shallower parts of the shelf, whereas

of these events was an expansion of the carbon-

The western part of the Barents Shelf was

ate shelf and widespread evaporite deposition in

partly transgressed during the Bashkirian, and

deep marine basins, as well as in shallow salinas

by Early Moscovian times carbonate shelf condi-

Deep and distal-marine environments existed

and marginal sabkhas.

ments accumulated in the depressions.

tions prevailed over the entire Barents-Kara Sea

over most of Novaya Zemlya and the eastern Pay

On Svalbard and in the westernmost parts

region, including parts of the previously conti-

Khoy. In these areas, there are deep water silici-

of the Barents Shelf, there was a return to depo-

nental, Visean, post-Caledonian landscape. At the

clastic deposits with manganese-bearing clayey

sition along narrow zones of subsidence along

onset of Moscovian time, continental conditions

siltstones interpreted as turbidites.

the major faultlines, similar to the conditions in

were presumably limited to horst-like features

the Tournaisian and Early Visean. En échelon ar-

along major tectonic lineaments in the west.

Farther to the east, the Hercynian folding resulted in the formation of a mountain range, and a

rangements of these troughs and local inversions

In the more central parts of the western Bar-

huge supply of clastic sediments was shed into the

indicate that strike-slip movements also occurred

ents Shelf, thick successions of evaporites, includ-

Kara Sea area. This led to an advance of continen-

in Bashkirian and Moscovian time. Alluvial fan

ing halite, accumulated in the deeper basins, such

tal environments across the eastern and central

deposits accumulated along the margins of the

as the Tromsø and Nordkapp basins. The salts of

parts of the Kara Sea. To the west, shallow-marine

relatively narrow basins. The fans graded later-

these basins were probably fringed by sabkhaic

environments continued to exist, and the sedi-

ally into ﬂoodplains, and farther out into marine

mixed carbonate and evaporite deposits.

mentary record is dominated by sandstones, bio-

environments. This resulted in a succession of interbedded clastics, carbonates and evaporites.

clayey deposits with sporadic silty and sandy sedi-

Moscovian

The Finnmark East area was partial emergent, but in some places salinas and possibly desert con-

clastic sandy limestones, siltstones and mudstones containing bryozoans, gastropods and bivalves.

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ = = =

N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N

74°0'0"N

^ ^ ^ ^^^^^^ ^^^^^^ ^ ^ ^

= =

= = =

= =

70°0'0"N

72°0'0"N

= = = =

= =

= = =

= =

== == == = = = = = = = = = = = = == == == = = = = = = = = = = = =

= =

== == == == == == == == = = = = = = = = = = = = = = = = = = = = = = =

= =

== == == == == == == == = = = = = = = = == == == == == == == == = = = = = = = =

= =

== == == == == == == == = = = = = = = = == == == == == == == == = = = = = = = =

= =

== == == == == == == == = = = = = = = = == == == == == == == == = = = = = = = =

=== === === === === = = = = = = = = = = = = = = == == == == == == == == = = = = = = = =

== =

== === === === === === = = = = = = = = = = = = = = == === === === === === === = = = = = = = = = = = =

= =

== == == == == == = = = = = = = = = = = == === === === === === === = = = = = = = = = = = =

= =

^ ^ ^ ^ ^ ^ ^ ^ ^^^^^^^^^^^^^^^^ ^ ^ ^ ^ ^ ^ ^ ^N ^N^ N^ ^N ^N^ N^ ^ ^ ^ ^ ^ ^ ^ ^N^NN^ØN^NN^ØN^NN^ØN^NN^Ø ^ Ø ^ ^ ^ ^ ^ ^ ^N^Ø N^ ^ØN ^N^Ø N^ ^ØN ^^^Ø^ ^Ø^ ^ ^ ^ ^ ^ ^ ^ ^N ^ØN^ N^Ø ^N ^ØN^ N^Ø^^N^Ø^ ^ ^ ^ ^ ^ ^ ^ ^N^Ø N^ ^ØN ^N^Ø N^ ^ØN ^^N^Ø^N^Ø^ ^ ^ ^ ^ ^ ^ ^ ^ N N^ N ^N N^ N ^ ^ N^ ^N ^N^ N^ N ^ ^ ^Ø ^ ^Ø ^ ^Ø ^ ^Ø^^ Ø^ ^N ^N^ N^ ^N ^N^ N^ N ^ N^ N ^ N ^N N^ N ^ ^NN^N^NN^N^NN^NN ^ N^Ø ^ ^Ø ^ ^Ø ^ ^Ø ^ ^Ø ^ØN^NN^N^NN^N^NN^N^NN^NN ^ ^N ^N^ N^ ^N ^N^ N^ ^ ^N ^N^ N^ ^N ^N^ N^ ^Ø ^ ^Ø ^ ^Ø ^ ^Ø ^ Ø^N^ N^ ^N ^N^ N^ ^N ^N^ N^ N ^ ^N ^N^ N^ ^N ^ ^ ^ N^ ^N ^N^ N^ N ^ ^Ø ^ ^Ø ^ ^Ø ^ ^Ø ^ ^Ø ^Ø^N ^N^ N^ ^N ^N^ N^ N ^ ^N ^N^ N^ ^N ^N^ N^ ^ ^N ^N^ N^ ^N ^N^ N^ ^ ^ ^ ^ ^ ^ ^ ^ ^N^ N^ ^N ^N^ N^ ^N ^N^ N^ N ^N N^ N ^N ^ N ^N^ N^ ^N ^N^ N^ ^ ^ N^ ^N ^N^ N^ N ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^N ^N^ N^ ^N ^N^ N^ N ^ N^ N ^ N ^N N^ N ^ N N N N N N N N N N N N N ^ N^ ^N ^N^ N^ N ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^N ^N^ N^ ^N ^N^ N^ N ^^^NN^^N^N^^N^ ^ ^N ^N^ N^^^NN ^N ^N^ N^ ^N ^N^ N^ ^ ^ ^ ^ ^ ^ ^ ^ ^N^ N^ N ^ ^N^ ^ N^ ^N ^N^ N^ N ^^^^^^^^^^ ^N ^ ^N^N^ N^ ^^^^^^^^^^^^^^^^ ^N^ N^ N ^N^ N^N N ^N ^^^^^

= =

Moscovian 311.7—306.5 Ma

76°0'0"N

78°0'0"N

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

= =

== == == = == == == == == = = == == = =

68°0'0"N

= =

30°0'0"E

40°0'0"E

50°0'0"E

Highland / Denudation area

Shallow-water shelf

Sandstone

Limestone, dolomite

N N N Halitic N N N N

Alluvial

Shelf

Siltstone / Clay

Limestone

Coast

Deep-water shelf

Limestone, sandstone

^^^^^ ^ ^ ^ ^ ^ Anhydritic / gypsiferous

Sabkha

Marl

Organogenic limestone

Ø =

= =

Cherty shale

Moscovian

Chapter 9

Stacked Palaeoaplysina build-ups from the upper build-up complex at Amfi on the northwestern part of BjĂ¸rnĂ¸ya. Photo: Geir Birger Larssen

Asselian Shallow carbonate shelves and deep basins

Palaeoaplysina packstone. Photo: Geir B. Larssen

In the Asselian, extensive shallow-marine carbonate shelves, intersected by deeper basins, covered the Barents Sea and Kara regions. The Svalbardian tectonics in the west had ceased, and deposition of warm-water carbonates took place in an icehouse world, with high-frequency and high-amplitude, eustatic sea-level changes. During sea-level highs, the entire shelf areas were flooded and shallow water platform carbonates with stacked organic build-ups developed in some areas.

predominately by evaporites with sabkha evap-

The distal turbidites are represented mainly by

Polygonal reef-pattern on the Loppa High

orites near the margins and local bioherms on

siliceous mudstones bearing carbonate manga-

structural highs. Contemporaneously, shales

nese ores (Kazarkinskaya and Mollerovskaya

3D seismic images on certain parts of the Loppa High have revealed a coherent polygonal reef pattern probably consisting of palaeoaplysinid-phylloid algal build-ups. The areas between the build-ups comprise dolomitised bioclastic wackestones and packstones with minor silt and sand and anhydrite nodules, suggesting a lagoonal to tidal-flat depositional environment. During sea-level lows, most of the structural highs were subaerially exposed, with a local development of karst. The majority of the margins of the Barents Sea region remained emergent throughout Asselian time, providing a thin, siliciclastic or mixed carbonate and siliciclastic rim around the basin. Local sources of clastic sediment e.g. the Loppa High, were temporarily exposed and acted as source areas during regressions (From StatoilHydro; Elvebakk et al.)

and carbonate mudstones were deposited in

formations). A maximum of manganese accu-

the deep basins in the eastern Barents and Kara

mulation has been observed in the Rogachev-

seas. A thick succession of salt was deposited in

Taynin and Sulmenev areas. Calcareous tur-

the Nordkapp Basin. Later, the salt developed

bidites contain conodonts of Asselian age

into 2-4 km-thick diapirs, and salt diapirs are

similar to those in the South Urals. Dark grey mudstones of the Glazov Forma-

sins. Evaporitic deposits are also known from

tion with few beds of carbonaceous siltstones

time-equivalent deposits on Svalbard.

are exposed along the western coast of Novaya

In the Asselian, the deposition of warm-wa-

Zemlya. Numerous carbonaceous, phosphatic

ter carbonates took place in a climate charac-

and barytic manganocalcite concretions are

terised by icehouse conditions, with high-fre-

also typical of this succession. A second facies

quency and high-amplitude, eustatic sea-level

type is represented by the Sesym Formation,

changes driven by glaciations in the southern

which consists of marls, claystones and orga-

hemisphere. During periods with high sea

nogenic limestones and mudstones, and is ex-

level, the entire shelf areas were ﬂooded and

posed in the eastern and northern parts of the

shallow-water platform carbonates with up to

Timan-Pechora Plate. These marine sediments

100 m-thick, stacked, palaeoaplysinid-phylloid

contain rare small foraminifers, ammonoids

algal build-ups were developed on structural

and bivalves.

highs such as the Finnmark Platform, Loppa

Numerous organic build-ups of diﬀerent

and Stappen highs, possibly the Sentralbanken

morphologies are traced along the margin of

High, and the eastern margin of the South Bar-

the Cis-Uralian trough, in the western part of

ents Basin. Interbedded, subtidal, high-stand

Novaya Zemlya, on the Kolguev Island and

carbonates and low-stand anhydrite deposits

also on the highs located within the oﬀshore

characterise the deeper parts of the platform.

and onshore parts of the Timan-Pechora area.

Halite deposition in the basin centres is suggest-

Based on deep drilling and seismic data, reefs

ed to have taken place during major low-stands,

were identiﬁed on the Barents Shelf where they

when platforms were subaerially exposed and

border the southern part of the South Barents

the basins were partly or totally separated from

Basin. Palaeoaplysina-, phylloid algae- and bry-

the open sea.

ozoan-dominated build-ups occur frequently.

4 km

also interpreted on seismic lines from other ba-

n the Late Carboniferous, the western

In central Spitsbergen, build-ups developed

Based on the analysis of structural and thick-

Barents Sea experienced a shift to gentle

parallel to the Billefjorden Lineament along

ness maps and seismic data, other areas of pos-

regional subsidence, as the Svalbardian

the eastern margin of the earlier Nordfjorden

sible development of reef structures are also

horst-graben tectonics had ceased. A close cor-

Block, and also extended some distance out

indicated on the paleogeographic map.

relation between Carboniferous rift structures

into the adjacent basin. On Bjørnøya, the lateral

Clastic deposits derived from the incipient

and the distribution of evaporite and carbonate

extent of the build-ups is more uncertain, but

Uralian Orogen to the east continued to accu-

deposits in the overlying Permian succession,

both axial and accretionary trends conform to

mulate in eastern parts of Novaya Zemlya and

suggests a component of diﬀerential subsid-

the basin pattern suggested by the underlying

started to appear in the distal, parts the Timan-

ence, probably induced by the earlier phase of

Kapp Hanna Formation.

Pechora Basin. Locally, inversion structures

crustal extension. The pattern of subsidence ap-

Shallow-water carbonate shelf settings with

that formed as a consequence of incipient Ural-

pears to ﬁt into a much broader regional picture

shoal, sand-bar and biostrom facies was also

ian compression, could have acted as sources

of a huge interior sag basin which by the end

developed at the southern and southwestern

of sediment during relative regressions. In the

of the Palaeozoic, came to encompass the entire

margins of the Timan-Pechora area. Towards

northeastern part of the Barents Sea region,

Barents Sea. The geodynamics of the regional

the central part of the Barents Sea there was

terrigenous deposits such as mudstones, sand-

sag is probably related to the closure of the Ural-

a transition from inner to outer shelf settings,

stones, siltstones, conglomerates and bioclastic

ian Ocean along the eastern margin of Baltica.

entering into a deep-water basin in the central

limestones of the Eksovskaya Formation were

The continent collision between Baltica and

eastern part of the area.

accumulated. In the eastern part of Novaya

the West Siberian Craton began in the south

Deep-water settings are indicated by the

Zemlya and Pay-Khoy, turbidites of the Tolbe-

around Middle Carboniferous times. The col-

distribution of distal and proximal turbidites

jakh and Kech-Pel formations are exposed. The

lision propagated northwards and reached the

in the eastern part of Novaya Zemlya and in

carbonate deposits in these formations contain

eastern Barents Sea in the Late Carboniferous

Pay-Khoy, where they can be traced towards

phylloid algae, bryozoans, corals, brachiopods,

to Early Permian.

the west. The proximal turbidite succession of

molluscs, crinoids and vertebrates. Close bio-

The western Barents Sea basins were semi-

the Tolbejakh and Kech-Pel formations reveals

geographic aﬃnities between Novaya Zemlya,

enclosed, with sea connections towards the

a cyclic alternation of gradationally bedded

Svalbard and Arctic Canada are indicated by

east through narrow straits, and were ﬁlled

sandy limestones, siltstones and mudstones.

the similarity of the fossil faunas.

Asselian

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ ^ ^ ^ ^ ^ ^ ^

Ø Ø

^ ^ Ø ^ ^ Ø ^ ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ Ø ^ ^ Ø ^ ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^ ^ ^ ^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^ ^ ^^ ^ ^^ ^ ^^ ^ ^^ ^^N ^^N^^ N^^ ^N ^ ^N ^^ ^^N ^^N^^ N^ ^ ^ N^^NN N N N N ^^^^^^^ ^ ^ ^ ^ ^ ^ ^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^ ^^^^^^^

Ø Ø

74°0'0"N

= =

Ø Ø

= =

Ø Ø

70°0'0"N

72°0'0"N

Ø Ø

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^

Ø Ø

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^

N ØN NØ N ØN ØNØ N N N N N N NØ N ØN NØ N N N N N N N N N N ØN NØ N ØN NØNN N N N N N Ø NN N N N N N N NØ N ØN NØ N N N N N N N N N N N N N N N N N N N N N N NØ ØN ØNØ NØ ØN Ø N N N N N N N N N N N N N N N N N N N N N ØN NØ N ØN N N N N N N N N ØN NØ N ØN Ø

Ø Ø

N N N N N N N N N N N N N N N ØN NØ N ØN N N Ø N ØN NØ N N N N N N Ø Ø N N N ØN N N ØN N ØN NØ N N N ØN N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N ØN Ø Ø NØ N N Ø N ØN N Ø N ØN NØ N N ØNØ NØ N Ø Ø Ø Ø Ø Ø Ø Ø N N N N N N N N N N^ N ^N N^ N ^N ^N NØ^ N Ø^N NØ^ NØ N ØN NØ N N Ø NØ N N Ø NØ ^ N^ Ø^N ^NØ^ N^ Ø^N ^ Ø N ØN N Ø N ØN N Ø N ØN NØ N N N N N N N N N N ^N ^N^ N^ ^N ^N^ N^ ØN NØ N Ø ØN N Ø NØ N N N N N ^ Ø Ø^N ØNØ^ NØ Ø^N Ø Ø Ø Ø Ø Ø Ø Ø

68°0'0"N

Ø Ø

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^

^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

ØØ ØØ

^^ ØØ ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

ØØ ØØ

^^ ØØ ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

ØØ ØØ

^^ ØØ ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

Ø Ø

Ø ØØ

ØØ

^^ ØØ ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

ØØ ØØ

^^ ØØ ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

30°0'0"E

Ø ØØ

^^ Ø ^ ^^ Ø ^^ Ø ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^Ø Ø ^ ^^ ^ Ø^ Ø ^^ ^ Ø^ Ø ^^ ^ Ø^ ^ Ø

= =

Ø Ø Ø = Ø= = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

= = = =

= =

^ ^= = Ø Ø = ^ Ø= ^ ^= = ^ Ø= = Ø Ø ^ Ø ^^ ^Ø Ø Ø ^ Ø ^^ ^Ø Ø Ø ^ Ø ^^ ^Ø Ø Ø ^ Ø ^^ ^Ø Ø Ø ^ Ø ^^ ^ Ø^ Ø Ø ^^Ø ^ Ø^ Ø Ø ^^Ø ^ Ø^ Ø ^ Ø

= = = = = = = = = = = = = = = = = = = = = = = = = = = Ø Ø Ø Ø Ø Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= =

Ø Ø Ø Ø Ø Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø

Ø Ø

Ø Ø Ø

Deep-water shelf

Clay, sandstone, siltstone

Ø Ø

Ø ØØ Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø ØØ ØØ Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø

Ø Ø

Coast

Marl

= =

^= = = = = = = = = = = = = = = = = = = = = = = = = = = = = ^ Ø=^ Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø Ø= Ø= Ø = Ø

Sandstone, siltstone, clay

Sabkha

= =

= =Ø = Ø = Ø = =Ø = Ø = Ø = =Ø = Ø = Ø = =Ø = Ø = Ø = =Ø = Ø = Ø = =Ø = Ø = Ø = =Ø = = Ø= Ø = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = = Ø = Ø= = =Ø = Ø = Ø= Ø Ø Ø Ø Ø Ø Ø

Shelf

Limestone

= =

= Ø = Ø= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

Ø Ø

Ø^ Ø^ Ø^ Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø^ Ø^ Ø^ Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø Ø

^ ^ ^ ^Ø ^ ^Ø ^ ^Ø ^

40°0'0"E

Deep basin

= =

= Ø = Ø= =Ø = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

= =

= Ø = Ø= =Ø = = = = = = = = = = = = = = = = = =Ø = Ø = Ø = = = = = = = = = = = == = = = = = =

= =

= Ø = Ø= =Ø = = = = = = = = = = = = = = = = = =Ø = Ø = Ø = = = = = = = = = = = = = = = = = =

Highlands / Denudation area

Shallow-water shelf

= =

Ø Ø

= =

Ø Ø

= =

Ø Ø

= =

Ø Ø

= =

Ø Ø

N N N N N N N N N N N N N N N N N

Ø Ø

^ ^ ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ Ø ^ ^ ^ ^ ^ ^ ^ ^ ^

Asselian 299.0—294.6 Ma

76°0'0"N

78°0'0"N

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

Ø Ø 50°0'0"E

Cherty shale

^ ^ ^ ^ ^ ^ ^ Anhydritic / ^ ^ ^ gypsiferous Build-ups

Limestone, sandstone

Limestone, dolomite =

ØØ

N N N N Halitic N N N N N N N

Ø Ø

Organogenic limestone Mn-ores

Asselian

Chapter 10 Bryozoans and brachiopods in the the Kapp Starostin Formation at AkselĂ¸ya, Svalbard. Photo: Morten Smelror

Wordian Temperate climate and extensive marine shelf

Skansen in Billefjorden, Svalbard. The upper, steep part of the mountain consists of Upper Permian cherts of the Kapp Starostin Formation. Photo: Morten Smelror

At the onset of the Wordian, the Barents Sea and Kara areas had been subject to major transgressions, and an extensive marine shelf with different shallow- and deep-marine depositional environments, covered the region. A shift in the climate during the Late Permian led to temperate conditions in the Wordian.

Bryozoans in the the Kapp Starostin Formation on Akseløya, Svalbard. Photo: Morten Smelror

Upper Permian cherts of the Kapp Starostin Formation exposed at Skansen in Billefjorden, Svalbard. Photo: Geir Birger Larssen

Bryozoans and brachiopods in the Upper Permian deposits at Treskelen, inner Hornsund, Svalbard. Photo: Morten Smelror

t the onset of Wordian time there

perate climate, had created perfect conditions

Throughout most of Novaya Zemlya and

were dramatic changes in the depo-

for swamp colonies, which were abundant

the adjoining Barents Shelf, a thick succes-

sitional scenarios throughout the

throughout the area. The Wordian deposits

sion of shallow-marine sandstones, siltstones

northern regions. The Carboniferous to Early

comprise mainly cherts and siliciﬁed carbon-

and mudstones accumulated. These sediments

Permian carbonate deposition came to an end,

ates, shales and siliciclastics, and are included

contain foraminifers, brachiopods, gastropods,

and was replaced by a siliciclastic regime. The

in the Tempelfjorden Group on Spitsbergen

bivalves and ammonoids. Deeper-water shelf

Wordian was also a period of overall transgres-

and in the Røye Formation on the western Bar-

conditions were to be found in the depressions

sion and an extensive marine shelf, with dif-

ents Shelf. Some areas, such as Bear Island, the

to the west of Novaya Zemlya.

ferent shallow- and deep-marine depositional

Loppa High and Southern Spitsbergen, were

In the central part of the South Island of

environments, covered the Barents Sea and

shallow-marine highs or even emergent at the

Novaya Zemlya, local slope settings were devel-

Kara regions.

time. These locations were dominated by banks

oped (Karamakulskaya Formtion). Here, a thick

In the Late Permian, the climate became

of bryozoans and brachiopods, and some of the

succession of sediments of gravity-ﬂow origin

cooler and changed from warm and arid to tem-

emergent sites also show evidence of marginal

has been identiﬁed, marked by turbidites and

perate. The gradual change from carbonates

marine mixed bioclastic and siliciclastic depo-

debris-ﬂow deposits. The ﬁne-grained deposits

to clastics was accompanied by a geographi-

sition.

in this succession contain large amounts of or-

cally widespread blooming of sponge species,

In the eastern shelf areas, a similar great va-

which came to inﬂuence the characters of the

riety of lithofacies can be distinguished. Near-

In the Timan-Pechora area, continued Late

main lithofacies of the Wordian succession.

shore marine conditions most likely existed in

Permian regression led to an expansion of the

An extensive spreading of silica spicules from

the northern part of the Timan-Pechora area, to

terrestrial areas. To the south, alluvial, lacus-

the sponges resulted in later siliciﬁcation of

the north of Novaya Zemlya, and in Severnaya

trine and lagoonal deposits were accumulated,

the sediments. Siliciﬁed carbonate lithologies

Zemlya. In the northern part of the Timan-Pe-

while in the northeast, coals and polymictic

dominate the Wordian deposits in many key

chora area, the thick Wordian succession shows

sands, silts and clays were deposited in alluvi-

locations, but a break towards siliciﬁed clastics

alternations of mudstones, deltaic sandstones,

al, swamp and lacustrine environments. Higher

and mud-dominated facies is seen in the upper

conglomerates and coals. In the northern part

up in the sequence they were replaced by talus

parts of the Wordian successions.

ganic matter.

of Novaya Zemlya the dominant lithology

cone deposits consisting mostly of boulders

A deep-water shelf environment existed in

comprises variously coloured sandstones and

and pebbles, possibly reﬂecting the evolving

the westernmost part of the Barents region. The

siltstones, with shallow marine faunas and ter-

Uralian orogeny to the east.

deeper-marine conditions, along with the tem-

restrial ﬂoras.

Wordian

# #

72°0'0"N

# #

68°0'0"N

# #

70°0'0"N

# #

# # #

# #

30°0'0"E

40°0'0"E

Highland / Denudation area

Wordian 268.0—265.8 Ma

78°0'0"N 76°0'0"N 74°0'0"N

50°0'0"E

Siltstone, clay

Sandstone, siltstone, clay, coal #

Lacustrine / Fluvial plain

Coast

Sandstone

Marsh / Lacustrine

Shelf

Clay, sandstone, siltstone

Delta

Deep-water shelf

Limestone, sandstone

Cherty shale #

Cherty limestone, shale Spiculite

Wordian

Chapter 11 The boundary between the Upper Permian Kapp Starostin Formation and the Lower Triassic Vikinghøgda Formation in Lusitaniadalen, Spitsbergen; marked by a red glow. Photo: Atle Mørk

Steep forset in a coarse-grained sandstone on Trondsennesset, Sørkappøya, Svalbard. Photo: Geir Birger Larssen

Induan Uralian uplift in the east and progradation into the shallow-water siliciclastic shelf

The Lower Triassic heterolithic succession of the Vardebukta Formation at Treskelen, Inner Hornsund, Spitsbergen. Photo: Geir Birger Larssen

In the Induan, an extensive supply of sediments from the developing Uralian orogen caused an extensive northwestward progradation of non-marine deposits in the eastern Barents Sea and Kara Sea regions. The greatest subsidence took place within the South Barents Basin and in the eastern part of Franz Josef Land, resulting in a continuous sedimentation of non-marine, near-shore and minor shallow-marine deposits. In the tectonically more quiescent western Barents Sea area, a shallow-water siliciclastic shelf existed.

North and northeast of the Finnmark Platform, a series of Early Induan shelf-margin progradations are observed on seismic sections as a series of northwest prograding clinoforms. The presence of several channels extending to the shelf margin may reﬂect a subaerial exposure of the shelf margin. Farther westwards in the Barents Sea area, the Triassic was generally a tectonically quiet period, marked by passive regional subsidence. However, minor movements occurred on the Bjarmeland and Finnmark platforms. More active faults are found along the Western Margin, where the Loppa High was uplifted and eroded in the Early Triassic as a consequence of rifting to the west of the high, as indicated by thickening in the Bjørnøya Basin. The Stappen High and parts of the Bjarmeland Platform may also have been exposed at times, forming possible islands with local, minor, sediment transport systems. 3D seismic image of an Early Triassic basin floor fan running northwards on the Finnmark Platform. (From StatoilHydro)

To the south, the Fennoscandian Shield was a sediment source area for the Finnmark Platform, the Hammerfest Basin and the Nordkapp

y the end of the Permian, tectonic move-

Tschernyshev Ridge. The most signiﬁcant sub-

on seismic, e.g. close to the Finnmark Fault

ments of the Uralian orogeny had led to

sidence took place in the Karataikhskaya and

Complex in the southern margin of the Ham-

closure of the marine connection from

Bolshesynjinskaya depressions, while a much

merfest Basin, prograding northwestwards oﬀ

the southeast to the Barents Sea. However, a

slower subsidence is recorded in the Kosju-

the contemporary shoreline.

marine link remained open to the west up to

Rogovsraya and Verkhnepechorskaya depres-

Marine conditions existed in the western

the time of development of the early Atlantic

sions. Basaltic eruptions occurred along faults

parts of the Barents Sea area at this time. The

rift system. This major regional change caused

conﬁned to the Karataikha depression and the

deepest parts possibly stretched through the

a signiﬁcant re-organisation of the basin physi-

Tschernyshev and Chernov ridges. Unlike in

Hammerfest Basin and across northern parts

ography. The rapid subsidence of the Russian

the Late Permian, the Triassic sedimentation in

of the Finnmark Platform and the Nordkapp

North and South Barents basins, which started

the Timan-Pechora area exhibits a transgressive

and Tiddly basins into the South Barents Ba-

in the Late Permian, continued throughout Early

trend. This is shown by the change from allu-

sin. Submarine fans may have developed from

Triassic time.

vial and stream-ﬂow deposits, into lacustrine-

the margins and towards the basin axis. The

swamp and deltaic sediments.

eastward extension of the sea is documented by

The Barents region received sediments from

Basin. Angular clinoforms are locally observed

the uplifted Novaya Zemlya, from the Uralian

In the Early Triassic, conglomerates, gravel-

shallow-water grey and black mudstones and

highlands in the east, from the Fennoscandian

stones and coarse-grained sandstones accumu-

siltstones on Franz Josef Land, which contain

Shield in the south, and possibly from local ex-

lated within the Cis-Uralian Trough. The thick-

foraminifers, pelecypods and ﬁsh remains.

posed areas to the west and northwest. Isotopic

ness of the succession diminishes from about

In the far west, sediment was supplied east-

and geochemical data from Lower to Middle Tri-

700 m to 200 m in a northerly direction. On the

wards from Laurentia into the northwestern

assic sandstones recorded from boreholes in the

Pechora shelf, the Lower Triassic strata (Chark-

Barents and Svalbard regions, as documented

Barents Sea and on Franz Josef Land show that

abozhskaya Formtion) comprise red mudstones

by relatively coarse-grained shoreface sands in

the Hercynian Uralian orogenic belt in the east-

and, less commonly, siltstones and sandstones,

the Sørkapp Land area. Farther north and east

ern part of the region was the main provenance

containing vertebrates, conchostracan, lingulids

on Svalbard, the Induan deposits are more ﬁne-

area. From this source area, Carboniferous to

and plants.

grained and contain common marine fossils

Triassic granites are recorded, and basic mag-

An alluvial plain existed in the eastern part

such as bryozoans, brachiopods, ammonoids,

matic complexes there show strong chemical

of the Barents Shelf and to the west of Novaya

pelecypods, gastropods, conodonts and ﬁsh re-

weathering and evidence of erosion.

Zemlya, on which predominantly alluvial and

mains.

Non-marine depositional conditions oc-

some lagoonal, red and variegated sandstones,

To the northeast, in the present position of

curred in the Timan-Pechora area and in the east-

siltstones and mudstones accumulated. The sed-

the Lomonosov Ridge in the Eurasia Basin and

ern part of the Barents Sea. The Urals and Pay-

iments contain plant remains, terrestrial verte-

the Arctic Ocean, an exposed land area was the

Khoy were the main provenance areas, though

brates and brackish-water bivalves. Thin layers

source of sediment supply into the northern

clastic material also came from the Timan up-

of tuﬀ occur in the lowermost parts of Triassic

Barents Shelf and towards Franz Josef Land.

lifts, the Pechora-Kozhvinski Mega-high and the

sections in Novaya Zemlya.

Induan

Induan 251.0—249.7 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

30°0'0"E

Highland / Denudation area

40°0'0"E

Shelf

50°0'0"E

Basaltic

Lacustrine / Fluvial plain

Sandstone

Marsh / Lacustrine

Siltstone, Clay

Fluvial / Deltaic

Clay, sandstone, siltstone

Induan

Chapter 12 Findings of free oil in septarian concretions from the Botneheia Formation on Svalbard led pioneering workers in the area to describe the dark,organic rich,mudstones as ”oil shales”. During a field excursion to Svalbard in the summer 2006 we found an ammonite (Aristoptychites trochleaeformis) coated with oil in the Botneheia Formation at Blanknuten on Edgeøya. When the ammonite was split in two the septa proved to be full of thick, degraded oil. At several places where the Blanknuten Member of the Botneheia Formation is exposed on Edgeøya we can recognise a distinct smell of oil. It should also be noted that early workers reported small seeps of oil in Upper Triassic sandstones elsewhere on Svalbard. (Photo: Hermann M. Weiss)

Anisian Enclosed, restricted basins in the west, near-shore and continental environments in the east

The Triassic succession on the NE side of Milne Edwardsfjellet. Anisian dark shale of the Botneheia Formation is exposed in the steepest parts of the mountain, with grey shale of the VikinghĂ¸gda Formation below. Photo: Atle MĂ¸rk

In the Anisian, organic-rich mudstones accumulated in a restricted, anoxic basin in the west, while non-marine deposits were replaced by near-shore sediments in the east. Continental siliciclastic deposits continued to be shed from elevated areas to the south and east (Fennoscandian Shield, Urals and Novaya Zemlya).

Dark, organic-rich, shales of the Botneheia Formation, Edgeøya. Photo: Geir Birger Larssen

uring Mid-Triassic times, the Barents

total organic carbon), and constitute a proliﬁc

and in the Murmanskaya area, where they con-

Sea comprised a central marine shelf

hydrocarbon source rock. The organic matter

stitute good hydrocarbon reservoir rocks. In

bordered by land areas to the north-

mostly comprises algal material. The organic-

the Murmanskaya area, the largest gas deposit

west, east and south. Open marine connec-

rich mudstones contain common marine fos-

is conﬁned to the Middle Triassic sandstones.

tions probably existed southwestwards into the

sils, including ammonites and marine reptiles,

In the East Barents Sea Basin there are

North Atlantic rift system.

and were deposited in an environment with a

widespread, grey, plant-bearing mudstones,

In the southwestern shelf area, sands were

restricted bottom-water circulation and high bi-

siltstones and sandstones deposited in alluvi-

derived from provenance areas on the Fennos-

otic production in the overlying water-column.

al-plain settings. The occurrence of siltstones

candian Shield and in the Urals and deposited

Southwards on the western Barents Shelf, simi-

and sandstones, with algae, foraminifers, rare

along the NE-SW-trending coastline. During

lar and time-equivalent, mudstone deposits are

molluscs and ostracods, is indicative of periods

maximum regression in the Early-Middle Ani-

assigned to the Steinkobbe Formation. The

when the coastal plain was transgressed and

sian, a northeast-directed system of clinoforms

total organic carbon content of these deposits

ﬂooded.

extended over the Finnmark Platform and

reaches up to 9%, and the mudstones are in-

Shallow-marine deposits (Matusevichskaya

Hammerfest Basin and on to the Bjarmeland

terpreted to have been deposited in a similar

Formation) are found in several places on

Platform. Sands, siltstones and shales were

restricted basin as the Botneheia Formation on

Franz Josef Land and the adjacent shelf area.

deposited in delta-front to shoreface environ-

Svalbard.

On Cheisa Island the formation shows a cyclic

ments along the paleocoastline (i.e., the Kobbe Formation).

In the eastern Barents Sea area, the Mid-

sedimentation with an overall shallow-marine

dle Triassic succession is represented mainly

regressive development. Dark grey and black

In western Spitsbergen, a series of mud-

by non-marine clayey siltstones, and in places

silty mudstones, with subordinate siltstone and

stones, siltstones and sandstones were de-

by variegated sandstones (Anguranskaya For-

sandstone beds, constitute the base of each cy-

posited in delta-front to pro-deltaic marine

mation). These deposits were accumulated in

cle. The content of organic matter is usually

settings (i.e., the Bravaisberget Formation).

lacustrine and ﬂood-plain settings within the

no more than 1%, and consists of more humus

Eastwards on Svalbard (Botneheia Formation),

Timan-Pechora area, including the southern

than sapropel. In the upper parts of the cycles,

and southwards on the Barents Shelf (i.e, the

part of the Pechora Sea shelf and the Kola Shelf.

siltstones and polymictic sandstones dominate.

Kobbe Formation equivalent), there was a re-

Sands were deposited in alluvial plain environ-

The biotas found in these deposits include fo-

stricted, anoxic basin with dominantly dark,

ments in central and eastern parts of the Khore-

raminifers, bivalves, ammonites and marine

organic-rich, phosphatic mudstones and cal-

jverskaya and Morejuskaya depressions.

phytoplankton.

careous siltstones. The mudstones locally have

Channel-ﬂow sands are found at the base of

high contents of organic matter (up to 12%

the Middle Triassic sequence on Kolguev Island

Anisian

* * * * * * * * * * * * * * * *

78°0'0"N

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

Anisian 245.0—237.0 Ma

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

* * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

76°0'0"N

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

74°0'0"N

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

72°0'0"N

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

70°0'0"N

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

68°0'0"N

30°0'0"E

40°0'0"E

50°0'0"E

Highland / Denudation area

Periodically flooded area

Basalts

Conglomerate, sandstone

Lacustrine / Fluvial plain

Coast

Sandstone

Organic-rich claystone

Fluvial

Shallow-water shelf Shelf

* * * * *

Sandstone, siltstone, clay Siltstone, clay

Anisian

Chapter 13 Carnian deposits of the De Geerdalen Formation on Edgeøya. Photo: Jan Stenløkk

Carnian Uplift in the east, with extensive westward coastal progradation

Deltaic sandstone lobes with growth faults in the lower part of the De Geerdalen Formation, Kvalpynten, EdgĂ¸ya. Photo: Geir Birger Larssen

Uplift and erosion in the eastern Barents Sea-Kara Sea region led to extensive westward coastal progradation and the development of continental and coastal-plain environments over the major part of the Barents Sea area, while marine environments were restricted to the westernmost parts. A volcanic province existed in the northeast.

he Carnian interval was generally marked by an overall regional regression in the entire Arctic region, and in

the Barents Sea area is characterised by an extensive westward progradation of near-shore and coastal depositional environments. The palaeogeographic reconstruction reflects the distribution of the depositional settings during the time of maximum progradation of the coastline. The seismic reflectors of this age continue westwards from the eastern Barents Sea to northwest of the Loppa High where they are downfaulted along post-Triassic faults possessing offsets of several kilometres. This implies that a widespread coastal plain probably stretched all the way from Novaya Zemlya and the Timan-Pechora area into the Hammerfest Basin and Fingerdjupet Subbasin to the west, with continental siliciclastic deposits also prograding from the northern Fennoscandian Shield. In the southwestern Barents Sea, sandstones and interbedded mudrocks of inferred estuarine - fluvial nature apparently form a persistent multistorey - multilateral sheet of amalgamated channellised deposits, separated from the underlying shoreface by a possible sequence boundary of intra-Early Carnian age. These deposits are, in turn, overlain by Upper

Root structures in Carnian delta plain facies. Hopen, Svalbard. Photo: Geir Birger Larssen

Carnian - Lower Norian, coal-bearing, coastalplain sediments with common red-bed development, interﬁngering westwards into more

ing incursions, but only in thinner metre-scale

The palaeogeographical development in

marine strata.

occurrences, indicative of minor transgressive

the eastern Barents Sea was mainly control-

In the northern Barents Sea, the marine ex-

cycles. The southwestern coast of Spitsbergen

led by the Pay-Khoy – Novaya Zemlya part of

tension stretched west of Hopen and Edgeøya,

reveals outcrops of near-shore settings prograd-

the Uralian Orogen, which led to an increased

thus providing a relatively narrow seaway to

ing oﬀ Laurentia from the westerly derived sys-

supply of clastic material from the uplifted ar-

Laurentia in the west. The extension farther

tems.

eas in the east. During the regional regressive

northwards across central Svalbard is more

West of Franz Josef Land a volcanic province

stage of development, continental, ﬂood-plain

uncertain, and it is possible that this marine

developed, and coastal-plain and deltaic sedi-

and deltaic environments were rapidly estab-

corridor extended to the northeast in Svalbard

ments with volcanic debris covered the north-

lished over the major part of the eastern Bar-

and into the area which later became the Atlan-

ern areas, including the eastern islands of the

ents Sea and Kara Sea areas. Here, the Carnian

tic rift system.

Svalbard Archipelago (i.e., the De Geerdalen For-

successions comprise interbedded mudstones,

mation), where they overlie Lower Carnian pro-

siltstones and sandstones with some beds or

delta deposits (Tschermakfjellet Formation).

lenses of coal. In the inner part of the South

Outcrop studies on eastern Svalbard (the De Geedalen Formation) reveal the same types

of lithology as seen in the southwestern Bar-

On Franz Josef Land the Carnian deposits

ents Sea and help to conﬁrm the regional depo-

are characterised by rhythmic alternations of

sitional picture of an extensive regional coastal

mudstones, siltstones and sandstones. This suc-

In the Kara Shelf area, Carnian deposits

plain and ﬂood-plain area. Excellent exposures

cession was deposited in a periodically ﬂooded,

have so far been identiﬁed only on seismic data.

in the steep coastal cliﬀs on western Edgeøya

nearshore environment. Interbeds of coal occur

In the Late Triassic, an epicontinental sedimen-

show sandstones deposited in a delta-front set-

in the upper part of the succession. Furthermore,

tary complex covered most of the South Kara

ting with an overall heterolithic coastal-/delta-

the strata contain common plant remains. The

Basin. This complex is 2-4 km thick, and can be

plain background environment. Also on Hopen,

upper part of the Gream Bell Formation consists

recognised at 4-6 km depth. The character of

well exposed lensoid channel geometries in a

predominantly of sandstones and siltstones,

the wave ﬁeld and layer velocity suggests the

dominantly heterolithic ﬂood-plain background

with plants fragments, marine bivalves and re-

presence of continental and near-shore marine

facies are revealed in the steep coastal cliﬀs. De-

mains of pleisosaurs. Fossiliferous Carnian de-

deposits comparable with those of the Tampey

tailed studies have shown that this depositional

posits are also found oﬀshore in the southern

complex in Western Siberia.

scenario is punctuated by smaller marine ﬂood-

and eastern parts of the Franz-Victoria Trough.

Carnian

Barents Basin, a brackish-water, intra-continental basin existed.

Carnian 228.0—216.5 Ma

68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

76°0'0"N

78°0'0"N

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

30°0'0"E

40°0'0"E

50°0'0"E

Basalt

Shale

Periodically flooded area

Sandstone

Coal

Coast

Conglomerate, sandstone

Shallow-water shelf

Siltstone, clay

Highland / Denudation area

Marsh

Lacustrine / Fluvial plain Alluvial

Carnian

Extensive channellised deposits on the western Barents Shelf

3D-seismic image from the Carnian delta off Finnmark, showing a large, sinuous meander belt. The meander belt is about 30 km wide, and the scrollbars are cut by a younger straight channel. The total area of the Carnian delta exceeded 90 000 kmÂ˛, nearly three times the area of the present-day Mississippi Delta.

Regional 2D seismic, with an extensive infill of 3D seismic areas, combined with well data and detailed interpretation of drillcores on the Finnmark Platform, in the Nordkapp Basin and on the Bjarmeland Platform, provide a unique possibility to assess the architecture and geometry of the Carnian channellised deposits. Lateral accretion of point bar migrations have been detected on seismics. On the Finnmark Platform, cross-bedded and massive sandstones of meandering, multistorey-stacked channels running from the Norwegian mainland are cutting into the underlying, fine-grained coastal-plain and floodplain deposits. This background environment (also revealed on the Bjarmeland Platform), with in situ coal beds and red/grey mottled paleosols, indicates a humid - temperate climate during this period. In the Nordkapp Basin, amalgamated tidal-influenced channels and bars were formed in a widespread estuary, overlying heterolithic tidal-flat deposits. Other 3Dâ&#x20AC;&#x201C;seismic morphological features indicate that the coastal-plain associations interfinger distally with marginal marine deposits in storm-dominated shoreline systems with possible barrier islands and linear beach ridges. (From StatoilHydro).

Carnian

Deltaic sandstone lobes in the lower part of the De Geerdalen Formation, Kvalpynten, EdgĂ¸ya. Photo: Morten Smelror

Chapter 14 Condensed cross-bedded sandstone of the SvenskĂ¸ya Formation at WilhelmĂ¸ya, eastern Svalbard. Photo: Geir Birger Larssen

Hettangian Wide continental lowlands

Sandstone with large-scale cross-stratification exposed at HĂĽrfagrehaugen, KongsĂ¸ya, eastern Svalbard. Photo: Geir Birger Larssen

In the Hettangian, wide continental lowlands covered most of the Barents Sea shelf area. Shallow-marine depositional environments were restricted to smaller basins in the west, where the coastal plains were periodically flooded.

Hettangian shales in the Wilhelmøya Subgroup at Domen, Sabine Land, east coast of Spitsbergen. Photo: Winfried Dallmann

uring the Late Triassic-Early Jurassic

northwest-prograding Tubåen Formation may

tal succession in many areas of the Barents Sea

time, large areas of the Barents Sea

interﬁnger laterally with marine shales. To-

region. In the east of the Barents Sea region,

Shelf were uplifted and eroded. In

wards the west, coastal plains aﬀected by brief

no Hettangian faunas have been found, but

the Hettangian, the central parts of the Barents

marine transgressions resulted in the accumu-

the non-fossiliferous deposits underlying the

Sea area, including the Loppa High, Svalbard,

lation of sands in tidal and estuarine channels.

Sinemurian-Plienbachian strata have conven-

Franz Josef Land, and the Timan-Pechora area,

The southern Hammerfest Basin was a major

tionally been assigned to the Hettangian. In the

comprised wide continental lowlands. Due to

depocentre, and the main provenance area was

inner part of the South Barents Basin, a Lower

the uplift and erosion, sedimentary rocks from

probably located to the south on the Fenno-

Jurassic sequence of sandstones with conglom-

this time interval are absent over large parts of

scandian mainland.

erate layers and coal lenses is correlated with

the region. Areas with shallow-marine environ-

On Svalbard, Hettangian deposits are rep-

the Hettangian and Sinemurian stages. Obser-

ments were restricted to smaller areas in the

resented by the Sjögrenfjellet Member of the

vations on seismic sections suggest that this

west, which were partially ﬂooded from time

Svenskøya Formation on Kong Karls Land.

sequence is thinning out towards the borders

to time.

Hettangian deposits might also be present on

of the basin. In the southeast of the Barents Sea,

During the Hettangian, sequences consist-

Wilhelmøya and Olav V Land on Spitsbergen,

the occurrence of ﬂuvial deposits and deltaic

ing predominantly of sand and assigned to the

but there are no speciﬁc datings to conﬁrm

sands, with sporadic thin beds of ﬂood plain

Tubåen Formation were deposited on the west-

this. The formation is dominated by sandstones

heterolithic deposits, indicates a coastal-plain

ern Barents Shelf. The formation represents

which most likely were deposited in tidal-ﬂat,

depositional environment.

tidal inlets, estuaries and lagoons, and is typi-

tidal-channel and coastal-plain environments.

In the South Kara Synecline, Hettangian-

cal for the Tromsø, Hammerfest and Nordkapp

The Sjögrenfjellet Member grades laterally into

Sinemurian deposits are recognisable on seis-

basins. In places, the formation contains coal

sandstones and conglomerates of the Teistber-

mic data. Here, the widely distributed Lower

layers, which are generally most abundant near

get Member of the Knorringfjellet Formation.

Jurassic succession of sandstones, siltstones

the southeastern basinal margins and die out to

The lack of age-diagnostic, biostratigraphic

the northwest. The shale content increases to-

guide-fossils precludes any reliable stratigraph-

wards the west and northwest, where the west-

ic subdivision of the Lower Jurassic continen-

Hettangian

and mudstones reaches up to 2 km in thickness.

Hettangian 199.6—196.5 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

30°0'0"E

40°0'0"E

Highland / Denudation area

Conglomerate, sandstone

Lacustrine / Fluvial plain

Sandstone

Marsh / Lacustrine

Sandstone, siltstone, clay

Periodically flooded area

Siltstone, clay

50°0'0"E

Hettangian

Chapter 15 Ammonites and bivalves in the KongsĂ¸ya Formation, WilhelmĂ¸ya. Photo: Morten Smelror

Toarcian Extensive coastal plains transgressed from east and west

The KongsĂ¸ya Formation at WilhelmĂ¸ya displaying unlithified heavily bioturbated fine grained sandstones deposited in an open marine shelf to a lower shoreface palaeoenvireonment. Photo: Geir Birger Larssen

In the Toarcian, the low-lying peneplains that developed during the Early Jurassic were transgressed from both the east and the west. A maximum transgression was reached in the Late Toarcian when shallow marine conditions were established in the Kara Sea area and in the western basins of the Barents Sea.

The mountain Hårfagrehaugen at Kongsøya displaying the uppermost Triassic to the lowermost Cretaceous sedimentary succession. Sandstone of the Kongsøya Formation is exposed in the middle part of the mountain slope. Photo: Geir Birger Larssen

Upper Toarcian sandstones of the Stø Formation in IKU core 7230/05-U-02 from the Nordkapp Basin. Photo: SINTEF Petroleum Research

n the latest Early Jurassic, most of the Bar-

Formation. By the Late Toarcian, these depos-

depositional environments were established

ents Region was dominated by low-lying

its were replaced by shallow-water mudstones,

over most of the western basins of the Barents

peneplains following the Late Triassic to

siltstones and clayey sandstones of the Gan-

Sea region. Sandstones, siltstones and minor

Early Jurassic denudation of the hinterlands.

zinskaya Formation, which contains common

shale of the Stø Formation were deposited in

During the Toarcian, a global sea-level rise led

foraminifers, bivalves and ammonites.

the Hammerfest, Nordkapp and Bjørnøya Ba-

to the establishment of shallow-marine condi-

During the Early Toarcian, deltaic and near-

sins and on the Bjarmeland Platform. The Stø

tions in the eastern and western parts of the

shore sands were deposited also in the eastern

Formation generally consists of stacked shore-

region.

Barents Sea Basin. Here, the sandstone succes-

face deposits with excellent reservoir qualities

In the east, the Kara Sea area was trans-

sion contains some siltstone layers that formed

in most localities where it has been targeted by

gressed from the Palaeo-Paciﬁc, while the west-

during transgressive pulses. Based on isotopic

drillholes.

ern basins were transgressed from the sea in

studies of sedimentary zircons from Barents

On Svalbard, shallow-marine sandstones of

the southwest. The western connection prob-

Sea wells, it is likely that the foldcomplexes of

the Wilhelmøya Subgroup were deposited in

ably also included an open seaway to the north-

Novaya Zemlya were the source of the sands. In

similar prograding coastal systems. The Bille-

west into the Proto-Canada Basin (Sverdrup Ba-

addition, the Pechora Plate could have served as

fjorden Fault Zone was active at this time, and

sin). The connection in the east is documented

an additional provenance area.

on the platform to the west of it the succession

by the similarity of the marine faunas of the

In the southeastern area, the Toarcian marine

is highly condensed and incomplete. East of the

Barents and Kara seas and the Northeast Rus-

deposits were represented by thin phosphate-

active fault zone, thicker and more continuous

sia, while the connection in the west is marked

bearing clays with rare siltstone and sandstone

successions are found in the basinal areas, as on

by the close similarities between Toarcian mi-

layers containing foraminifers, bivalves and re-

Kong Karls Land. Over the platform areas of the

croplankton assemblages from the western

mains of plants. On the Jamal Peninsula within

western Barents Shelf the Toarcian deposits are

Barents Sea, North Sea and the Central Europe

the South Kara Basin, Lower Toarcian deposits

unevenly preserved, partly due to the dynamic

domain.

comprise dark grey and black shale of the mid-

coastal depositional regime and partly because

In Toarcian time, the Kara Sea and Barents

dle Dzhangotskaya Formation. In the Late Toar-

of subsequent erosion following the initiation

Sea basins were separated by the mountain

cian, the marine basin became shallower, and

of diﬀerential tectonic movements in the Mid-

ranges of Novaya Zemlya. To the southwest

the typical marine mudstones were replaced

Jurassic. Phosphatic conglomerates are found

of these mountains, a lowland existed in the

by siltstones and sandstones, and minor mud-

in the Upper Toarcian succession at several

Pechora area and in the southern Barents Sea

stones of the upper Dzhangotskaya Formation,

locations (Hammerfest and Nordkapp basins,

region.

deposited in coastal environments.

Wilhelmøya, Sørkapp Land on Spitsbergen).

In the Early Toarcian, shallow-water condi-

In southwestern Barents Sea area, an Early

Nodules of these conglomerates are commonly

tions occupied Franz Josef Land, where there are

Toarcian transgression led to a change from

found preserved as remanié deposits of the Ba-

sands, sandstones with conglomerate interbeds

ﬂood-plain environments to prograding coastal

thonian Brentskardhaugen Beds on Svalbard.

and coal lenses assigned to the Tegetkhovskaya

settings. In the Late Toarcian, shallow-marine

Toarcian

Toarcian 183.0—175.6 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

Highland / Denudation area

Sandstone

Periodically flooded area

Siltstone, clay

Coast

Clay, siltstone, sandstone

Shallow-water shelf

Sandstone, siltstone, clay

Toarcian

Chapter 16 Detail of the lithology at the boundary between the underlying Svenskøya Formation and the overlying Kongsøya Formation at Hårfagrehaugen, Kongsøya, eastern Svalbard. Photo: Geir Birger Larssen

Bajocian Central uplift, maximum regression and prograding coastlines in the west and east

Megaripples in the very condensed Knorringfjellet Formation, a few metres below the Bathonian Brentskarhaugen conglomerate, at Tilasberget, Van Keulenfjorden, Svalbard. Photo: Winfried Dallmann

During the Bajocian, the Middle Jurassic regression reached its maximum. The central areas of the Barents Sea were uplifted and exposed to winnowing and variable erosion. The coastline prograded towards both east and west, leading to continental and near-shore shallow-marine conditions over major parts of the Barents Sea region.

Provenance of Middle Jurassic sandstones The provenance area that provided the sediment for the Middle Jurassic sandy members in the Shtokman area is still under discussion. It is suggested that the reservoir sands were eroded from intra-basinal uplifts located to the west during the Early-Middle Jurassic. Accessory detrital zircons recently separated from the Lower Jurassic sandstones in the Shtokman deposit show the ages of 173 Ma, 189 Ma, 255 Ma, while Middle Jurassic sandstones have 12 separate U-Pb zircon age populations as follows: 211 Ma, 227 Ma, 220 Ma, 262 Ma, 301 Ma, 332 Ma, 348 Ma, 383 Ma, 414 Ma, 448 Ma, 465 Ma and 507 Ma. These ages suggest that the Lower Jurassic sandstones in the Shtokman Field deposit were formed as a result of erosion of fold complexes on Novaya Zemlya, where Late Permian to Early Jurassic, acidic magmatic rocks are present. The erosional truncation within the denudation area was insignificant when the Early Mesozoic sedimentary-magmatic complex was eroded. The Mid Jurassic sandstones contain, together with Late Triassic zircons, also a large number of zircons with widely varying ages. These reveal an increasing erosional truncation in Middle Jurassic time, and point to erosion of Cambrian to Permian rocks, which are widely distributed in northern Novaya Zemlya.

Bajocian shallow marine sandstones of the Stø Formation from borehole 7230/05-U-02, Nordkapp Basin. Photo: SINTEF Petroleum Research

n the Bajocian, the Middle Jurassic regres-

Barents Region and in the Timan-Pechora area,

more distal locations, sandy, silty and clayey

sion reached its maximum. Large parts of

mostly coarse-grained, continental to marginal

non-marine deposits of the Syssol Formation

the shelf were exposed to erosion, and a

marine, clastic sediments were deposited. The

were distributed over the rest of the Timan-

depositional gap is observed over most of the

content of siltstone and shale increases north-

Pechora area. During the Bajocian, subsidence

western Barents Shelf. Marine environments

wards into the marine South Barents Basin.

commenced in the Pechora area, which was

were restricted to western and eastern areas.

In the South Barents Basin, a thick cyclic

transgressed from the south. The non-marine

The presence of Bajocian shallow-marine de-

clay-sand sequence, consisting of four to six

deposits were replaced by marine sands and

posits in the Nordkapp Basin and the western-

transgressive-regressive cycles, was deposited

clayey-silty deposits which contain phyto-

most parts of the South Barents Basin suggests

in a shallow shelf environment during the

plankton and foraminifers together with con-

the existence of an open seaway connecting the

Middle Jurassic. The cycles begin with pre-

tinental ﬂoras.

western and eastern marine basins.

dominantly silt-clay or clay units, grading up-

The Middle Jurassic sedimentary basin of

Due to the syn-depositional uplift and win-

wards into sands. The thickness of the sandy

the South Kara Region had restricted connec-

nowing, and also to later Mid-Late Bathonian

layers varies from 25 to 70 m. The porosity of

tions with the sea, being surrounded in both

diﬀerential erosion, Bajocian sediments are

the sands reaches 16 to 19%, and productive

the west and the east by the Pay-Khoy-Novaya

generally missing or poorly preserved in the

gas-bearing horizons (Shtokman, Ludlow and

Zemlya mountain belt. Based on results from

western and central Barents Sea area. Shallow-

Ledovoje areas) are conﬁned to these units.

drillings on Sverdrup Island, it has been sug-

marine sandstones assigned to the Stø Forma-

To the north, on the Franz Josef Land ar-

gested that the North Siberian Rapids was sub-

tion are found in the westernmost part of the

chipelago, the Bajocian strata are dominated by

jected to erosion and denudation. In Bajocian

Hammerfest Basin and in the Nordkapp Basin.

clays in the south and southwest, and by mud-

time, the Jamal Peninsula on the east side of the

On Svalbard Bajocian, deposits are generally

stones and siltstones in the east. The sediments

Kara Sea was covered by a shallow sea. There,

only found as reworked pebbles, often con-

contain marine faunas such as foraminifers, bi-

predominantly dark grey mudstones and clay-

taining marine fossils, in the subsequent Late

valves, belemnites and ammonites.

ey siltstones (Leontievskaya Formation) were

Bathonian Brentskardhaugen Beds.

102

The Urals and the Timan Range were prob-

deposited, together with thin sandstone layers

In the eastern part of the Barents Sea, a ma-

ably the main provenance areas for the con-

containing plant detritus and marine shelly

rine basin existed in the area of the South Bar-

tinental sediments which accumulated in the

faunas.

ents Basin. The elevated areas of Novaya Zemlya

Timan-Pechora area, and the accumulations of

separated this basin from the marine basin in

sands, gravels and conglomerates were prob-

the Kara Sea area. In the southern parts of the

ably deposited on extensive alluvial plains. In

Bajocian

Bajocian 171.6—167.7 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

30°0'0"E

40°0'0"E

50°0'0"E

Highland / Denudation area

Coast

Conglomerate, sandstone

Siltstone, clay

Lacustrine / Fluvial plain

Shelf

Sandstone

Clay

Alluvial

Sandstone Sandstone, siltstone, clay

Bajocian

103

Chapter 17 Ammonites in the Upper Jurassic Agardhfjellet Formation on Spitsbergen. Photo: Hans Arne Nakrem

Tithonian Maximum transgression on an extensive shelf

Upper Jurassic dark shales at Janusfjellet (in front) and Konusfjellet (behind) on Spitsbergen. Photo: Hans Arne Nakrem

During the Tithonian, the Late Jurassic transgression reached its maximum. This resulted in deposition of predominantly clayey sediments in open marine environments over most of the Barents Region. Near-shore environments existed in the southeastern parts of the Pechora area, while deep-water environments prevailed in the central and northern parts. Sandy, coastal, Middle Tithonian sediments on central Spitsbergen suggest the presence of a palaeo-coastline to the north and northwest, with deeper basins towards the south and southeast.

Remains of a plesiosaur found in the Upper Jurassic Agardhfjellet Formation on Spitsbergen. Photo: Hans Arne Nakrem

106

Bivalves of the genus Buchia in the Upper Jurassic Agardhfjellet Formation on Spitsbergen. Photo: Hans Arne Nakrem

uring the Tithonian, the Late Jurassic

developed in the central parts of Spitsbergen.

the Izhma-Pechora Synecline, Malozemelsko-

sea-level reached its maximum, and an

The unit thins laterally both eastwards and

Kola Monocline, Kolva Megahigh and Khorey-

extensive marine shelf covered most

westwards. The sandy, coastal, Middle Titho-

ver Depression, a bituminous mud accumulat-

of the Barents Sea and Kara Sea. On this open

nian sediments on central Spitsbergen suggest

ed, which later became a proliﬁc oil-shale. On

marine shelf, dominantly shales and mudstones

the presence of a palaeo-coastline to the north

Kolguev Island, the Middle to Upper Tithonian

were deposited, with subordinate thin inter-

and northwest, with deeper basins towards the

Paromesskaya Formation contains a thick bitu-

beds of limestones, siltstones and sandstones.

south and southeast. Overlying the Oppdal-

minous clay member in the lower part, and silt-

The depositional environment varied from rel-

såta Member is the Middle-Upper Tithonian

stone beds in the middle part. The northeastern

atively shallow to deep marine, with inferred

Slottsmøya Member, which comprises domi-

part of the Barents Sea area is characterized by

water depths of 200-300 m over large areas.

nantly black shales, in some places developed

more shallow-water marine environments.

Bottom-water conditions were predominantly

as paper shales, deposited in a restricted shelf

On Franz Josef Land, the Tithonian sedi-

dysaerobic to anoxic, due to local submarine

environment. The total organic content of these

ments are assigned to the Gansijskaya Forma-

barriers and basins resulting from Cimmerian

deposits peaks at 5% in some layers.

tion. It is composed of dark grey and black

tectonic movements. Low sedimentation rates

In the western and northwestern parts of

mudstones in the lower part, and siltstones and

and an input of mostly ﬁne-grained clastic sedi-

the Barents Shelf, Tithonian deposits comprise

ﬁne-grained sandstones with bivalves and am-

ments, combined with a relatively high organic

dark shales of the Hekkingen Formation (Krill

monites in the upper part.

productivity in the overlying water-column, led

Member). The formation typically represents

To the south, black silty and organic-rich

to signiﬁcant accumulations of organic matter

an open marine shelf depositional environ-

clays were deposited in a deep shelf environ-

in the bottom sediments.

ment, with oxygen-depleted bottom-water con-

ment that extended across the Murmanskaya

In the western Barents Sea, the Cimmerian

ditions. On the Bjarmeland Platform, the Titho-

and Severo-Murmanskaya areas. To the north

movements initiated a continued uplift of the

nian-Berriasian boundary is marked by a thin,

at the Arcticheskaya, Shtokmanskaya, Lud-

Loppa High and the Stappen High. The Sentral-

very organic rich unit with a proliﬁc accumula-

lowskaya and Fersmanskaya areas, Tithonian

banken High, the Hopen High and the Hjalmar

tion of algal material, possibly originating from

deposits are represented by dark carbonaceous

Johansen Dome were inferred to have been up-

an algal bloom induced by the Mjølnir meteor-

shales, with a total organic content (TOC) up to

lifted and partly eroded during this period.

ite impact. The unit is termed the Sindre Bed of

16.5%. Upwards in the succession these organ-

On Svalbard, the Tithonian deposits are rep-

the Ragnarrok Formation and contains ejecta

ic-rich deposits are replaced by organic-poor

resented by dark grey to black silty mudstones

material with iridium anomalies and shocked

grey mudstones with TOC generally below

and minor siltstones and ﬁne sandstones of the

quartz grains from the Mjølnir impact. The unit

2.5%. In the South Barents Basin, the Tithonian

Agardhfjellet Formation. The most silty and

marks a distinct Tithonian-Berriasian bound-

succession is composed of carbonaceous clays.

sandy unit is the Middle Tithonian Oppdalsåta

ary marker across the Barents Sea.

The thickness of the succession is signiﬁcantly

Member, which constitutes the middle part of

In the east on the Barents Shelf and in the

reduced on the Central Barents highs due to a

the formation. This member represents shallow

Kara Sea area, similar depositional environ-

cumulative eﬀect of syn-depositional uplift and

shelf, sandbar-associated deposits and is best

ments existed. In some isolated areas within

subsequent Berriasian erosion.

Tithonian

I I

30°0'0"E

40°0'0"E

Tithonian 150.8—145.5 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

50°0'0"E

Highland / Denudation area

Shallow-water shelf

Sandstone

Lacustrine / Fluvial plain

Shelf

Sandstone, siltstone, clay

Coast

Deep-water shelf

Clay, sandstone, siltstone

Organic-rich claystone I

Black shale (organic-rich)

Tithonian

107

Chapter 18 Photos of thin-sections from the Klippfisk Formation in the type section, core 7430/10-U-01, Bjarmeland Platform. Photos: Atle MĂ¸rk

Core with condensed carbonates of the Klippfisk Formation from borehole 7430/10-U-01 on the Bjarmeland Platform. Photo: Atle MĂ¸rk

Valanginian Open marine shelf

Louiseberget on Svalbard, Lower Cretaceous dark shale of the Rurikfjellet Formation, with overlying sandstones of the Helvetiafjellet Formation above an erosional unconformity. Photo: Ivar Midtkandal

During the Valanginian, most of the Barents Sea area was an open marine shelf. The well-aerated basins received mainly fine-grained clastic deposits, whereas the structural highs and platforms separating the basins were the sites of condensed carbonate deposits.

Cool Valanginian sea-temperatures Our current knowledge of the palaeoclimate and oceanic circulation patterns for the Cretaceous is sparse and contradictory. The traditional view of warm, equable, global climates has been challenged in recent years as new evidences of Early Cretaceous icehouse conditions, or at least cool climates, have been gathered. Such evidence includes the finding of glendonites in Valanginian strata from the Sverdrup Basin (Arctic Canada), the occurrence of ice-rafted deposits in Australia, Siberia and on Spitsbergen, and isotope studies on endemic belemnites from the Valanginian of Kong Karls Land. The studies on belemnites has revealed cool, high latitude, marine isotopic palaeotemperatures (7.7°C) during the Early to Middle Valanginian times and suggest the presence of high-latitude ice.

n the earliest Cretaceous, the overall re-

stones with bivalves (Buchia) and belemnites.

elsewhere close to the uplifted structural highs

gression which began in the latest Jurassic

Comparable condensed carbonate units are also

and along the shelf-edge.

continued. The opening of the Amerasian

found on structural highs on the Bjarmeland

To the east in the Timan-Pechora area, there

Basin in the Arctic Ocean caused an uplift and

Platform and along the margin of the Nordkapp

are marine near-shore deposits consisting

gentle tilting in northern parts of the Barents-

Basin to the south. A pronounced unconform-

mostly of silts and rare sands and clays. During

Kara region. This again led to an increased

ity occurs between Upper Jurassic dark shales

the Valanginian, an increasing supply of terrig-

terrigenous supply from the north. Compared

and the overlying units of Lower Cretaceous

enous sediments resulted in lithological chang-

with the Late Jurassic, the areas of marine sedi-

(Valanginian to Early Barremian) condensed

es in the inner parts of the South Barents Basin.

mentation were reduced, but an open marine

carbonates and marls on these elevated areas.

In the Early Valanginian, clay deposits with fo-

connection was maintained through into the

The condensed units also contain several ma-

raminifers, bivalves and arthropods were wide-

Tethys Ocean in the south. In Early Cretaceous

jor and minor stratigraphic gaps reﬂecting a

ly distributed in the basin, whereas in Late Va-

time, icehouse conditions with repeated glacia-

complex interplay between local tectonic move-

langinian time silts and sands with a variety of

tions are considered to have existed based on

ments and eustatic sea-level changes during the

marine faunas and plants appeared. As deltaic

the presence of possible ice-rafted deposits on

Early Cretaceous.

deposits continued to prograde in the transi-

Spitsbergen and from isotope studies on endemic belemnites from Kong Karls Land.

110

Belemnites from Kong Karls Land. Photo: Morten Smelror

On Spitsbergen, Valanginian clay deposits

tion from Valanginian to Hauterivian time, ex-

with minor carbonates were accumulated in

tensive clinoforms were developed. The largest

In the northernmost part of the region, near-

shallow-marine to prodeltaic environments

clinoforms, which are hundreds kilometers in

shore marine environments existed at this time.

(i.e., the Wimanfjellet Member of the Rurik-

strike length and up to 100 m thick, occur in

On Franz Josef Land, marine sedimentation

fjellet Formation). The earliest Early Creta-

the northern part of the mega-trough. Smaller

was restricted to areas south and southeast of

ceous succession shows an upward-shallowing

clinoforms are known in the Kola-Kanin Mono-

the islands. Here, quartz sandstones and sandy

trend due to the initial uplift of the areas to the

cline and close to the local Severomurmansk,

limestones with ammonites and bivalves were

north.

Murmansk and probably Kurentsov uplifts. On

deposited in near-shore environments (i.e., the

In the deeper parts and outer shelf environ-

the arches of these uplifts, the Berriasian and

Lamonskaya Formation). The northern and

ments on the southwestern Barents Shelf (Ham-

Lower Valanginian deposits are usually absent,

western parts of the archipelago were elevated,

merfest Basin, Bjørnøya Basin), thicker units of

and the Lower Cretaceous succession starts

and on this land area with semi-humid envi-

clay deposits, with thin limestone and dolomite

with Upper Valanginian -Hauterivian strata.

ronments, a ferrisialic weathering crust was

layers, were deposited (i.e., the Knurr and Kolje

During Early Cretaceous time, marine sand-

developed.

formations). Here, the sedimentation was more

stones and mudstones were deposited over

Westwards on Kong Karls Land, the Val-

continuous than on the structural highs and

most of the South Kara Basin. Seismic proﬁles

anginian is represented by condensed inner

platform areas, the clastic content was higher,

show the presence of clinoforms extending

shelf deposits comprising silty limestones and

and there were fewer carbonate beds. Down-

from the east and southwest (Pay-Khoy and

marls (i.e., the Tordenskjoldberget Member of

ﬂank of the Loppa High towards the Hammer-

Novaya Zemlya region) into the axial part of

the Klippﬁsk Formation). The condensed de-

fest Basin, there is a thick sandy unit of sub-ma-

the basin.

posits contain bivalve coquina interbeds. Up-

rine Lower Cretaceous sub-marine fan deposits.

wards in the formation there are sandy lime-

Similar fan deposits were probably deposited

Valanginian

Valanginian 140.2—136.4

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

30°0'0"E

40°0'0"E

50°0'0"E

Lithology

Enviroment Highland / denudation area

Shelf

Sandstone, siltstone, clay

Coast

Deep-water shelf

Siltstone, clay

Shallow-water shelf

Deep basin

Clay

Limestone

Valanginian

111

Chapter19 On Svalbard, there are several records of dinosaur tracks in the Barremian Helvetiafjellet Formation. The first tracks were discovered at Festningen in 1960, followed by later findings at Kvalvågen, Grønfjorden and Austerbogen on Sørkapp. The tracks include both ornithopods and theropods. So far, no body remains have been found. Consequently, we cannot say exactly which dinosaurs lived on the coastal plains of Svalbard in the Barremian. However, the discovery of the tracks raises the question as to how such large reptiles were able to live in climatic conditions as far north as 60°N palaeolatitude. More recently, the tracks from Svalbard have been followed by discoveries of dinosaur remains from Alaska, northern Canada and Siberia, and the common picture of dinosaurs as tropical animals, which lived under warm to temperate climates in the Mesozoic, is now being questioned.

Dinosaur track in the Barremian Helvetiafjellet Formation at Austbogen on Spitsbergen. Photo: Morten Smelror

The lower boundary of the Helvetiafjellet Formation at Myklegardfjellet, east Spitsbergen. Photo: Ivar Midtkandal

Barremian Tectonic uplift and prograding deltas in the north

Lower Cretaceous basalts capping Bell Island, Franz Josef Land. Photo: VSEGEI

In the Barremian, tectonic uplift of the northern Barents Shelf area continued and caused an overall regression and development of more continental conditions. Large deltas prograded from the uplifted areas in the north towards the subsiding basins in the south. On Svalbard and Franz Josef Land, the vertical tectonic movements were accompanied by volcanic activity.

Barremian sandstones of the Helvetiafjellet Formation, Spitsbergen. Photo: Morten Smelror

114

Lower Cretaceous basalts on Bell Island, Franz Josef Land. Photo: VSEGEI

n the Barremian, the tectonic uplift of the

To the south on the western Barents Shelf,

number of silt and sand layers increased. At the

northern Barents Shelf area continued.

distal open marine conditions prevailed, with

Shtokman-Luninski area, close to the northern

On Svalbard, the marine Valanginian-

predominantly muddy sedimentation (Kolje

margin of the South Barents Basin, about 50%

Hauterivian sedimentation was replaced by

Formation). A marked regional transgression

of the Barremian strata consist of sand and silt.

Barremian continental and near-shore marine

took place in the Mid Barremian, leading to a

In addition to the marine fauna (foraminifers,

deposition of the Helvetiafjellet Formation.

marked shift in facies from condensed carbon-

bivalves and ostracods), plant remains are also

Here, sands, silts and coal layers (50-135 m

ates to dark shales on the structural highs and

recorded in the sediments.

thick) with abundant plant remains were de-

platform areas.

On the South Kara Shelf, Barremian deltaic

posited. Similar deposits, representing interact-

In Early Barremian time, near-shore marine

sands and silts accumulated in the upper Neo-

ing ﬂuvial, delta-plain and shallow marine en-

environments prevailed in the Timan-Pechora

comian clinoform complex. On the Jamal Pe-

vironments, are recorded on Kong Karls Land.

area. Here, clays and silts, with foraminifers,

ninsula and Belyi Island, there is a succession

The Barremian succession represents one long-

bivalves, ammonites and belemnites, were de-

of clays, silts and sands of the Tanopchinskaya

term cycle of falling and rising sea-level caused

posited. By the end of the Barremian, an uplift

Formation, with the amount of coarse-grained

by the tectonic uplift, tilting and subsidence of

of the entire region had taken place, resulting

sediments decreasing towards the north.

the Svalbard Platform.

in an overall change from marine to continen-

The climate in the Early Barremian is tra-

On Svalbard and Franz Josef Land, the ver-

tal conditions. Glauconitic clays, with rare sand

ditionally thought to have been humid, as sug-

tical tectonic movements were accompanied by

lenses containing foraminifers, bivalves, am-

gested by the numerous coals deposits derived

volcanic activity. On Franz Josef Land there are

monites and rare plant remains (Moshjugin-

from a rich vegetation cover. The Barremian,

10-70 m-thick ﬂows of basaltic lava with inter-

skaya Formation), were typical sediments on

humid, boreal rain forest was composed pri-

relations of coal-bearing, ﬂuvio-deltaic strata

the Pechora Shelf. A succession of clays with

marily of seasonally deciduous conifers and

forming the lower Armitidzhskaya Formation.

interbeds of silts and glauconitic sands shows

ginkophytes with a lower-level vegetation of

Coal beds are most common in the upper part

that similar near-shore marine settings also ex-

ferns, sphenophytes, pteridosperms and cyca-

of the succession. The sediments were deposit-

isted in the southern part of the Barents Sea

dophytes. At this far north (60°N) there was

ed in swamps and marshes, lakes, and in brack-

(i.e., in the Severo-Kildinskaya, Murmanskaya

probably a marked seasonality in climatic con-

ish water and shallow-marine environments.

and Severo-Murmanskaya areas).

ditions, with signiﬁcant periods of darkness.

Together with the extrusive basalts, pyroclastic

In the South Barents Basin, a shallowing of

However, there are no indications of any ex-

and conduit volcanic rocks are widely distrib-

the epicontinental sea occurred during the Bar-

tensive ice caps. In Late Barremian time, in NE

uted in the southeastern parts of Franz Josef

remian. In the marginal inner part, a predomi-

Europe there seems to have been a signiﬁcant

Land.

nantly clay sedimentation continued but the

change in climate to more arid conditions.

Barremian

Barremian 130.0—125.0 Ma

78°0'0"N 68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

76°0'0"N

+ ++ ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ ++ +

+ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ + + ++ ++ ++ ++ ++ ++ ++ + + ++ ++ ++ + + ++ ++ ++ ++ ++ ++ + + + + + + + + + + ++ ++ ++ + + ++ ++ ++ + + + + + + ++ ++ ++ ++ + + ++ ++ ++ + + ++ ++ + + ++ ++ ++ +

30°0'0"E

40°0'0"E

50°0'0"E

Highland/ Denudation area

Shallow-water shelf

Basalts

Siltstone, clay

Fluvial / Deltaic

Shelf

Sandstone

Shale

Coast

Deep-water shelf

Sandstone, siltstone, clay

Deep basin

Barremian

115

Chapter 20 Albian sediments (Kolmule Formation) in IKU core 7230/05-u-09 from the Nordkapp Basin. Photo: SINTEF Petroleum Reseach

Albian Uplift in the northeast, deeply subsiding basins in the west

Albian open marine deposits in the upper part of the Carolinefjellet Formation, below a prominent cliff of Tertiary Firkanten sandstone, at Zillerberget, Torell Land, Svalbard. Photo: Winfried Dallmann

During the Albian, the northeastern Barents Sea area was uplifted and large amounts of sediment were shed from the uplifted continental areas in the northeast into deeply subsiding basins in the west. Volcanism continued on Franz Josef Land and Kong Karls Land.

n Albian time, the Barents Sea region com-

of the East Barents Basin, the Upper Aptian-

(i.e. the Kolmule Formation). Syn-rift sedimen-

prised uplifted land areas in the northeast

Lower Albian sandstones, siltstones and clays

tary wedges are recognised in several of the

and marine shelves in central and west-

were followed by Middle and Upper Albian

rapidly subsiding western basins. Towards the

ern parts. As a result of the uplift, sediments

clays and silts containing abundant foraminif-

proximal areas in the north, northeast and east,

prograded from the northeastern areas into

ers and radiolarians.

the amount of sand increases as the deltaic and

rapidly subsiding basins along the western

In the southeast, the Pechora Basin was

margin (i.e., the Harstad, Tromsø and Bjørnøya

uplifted, and the marine connection to Tethys

On Svalbard, near-shore and shallow-ma-

basins). These basins were decoupled from the

across the Russian Platform was restricted. In

rine, clayey, silty and sandy sediments were

rest of the Barents Shelf during the Early Creta-

the Timan-Pechora area, the Aptian deposits

deposited during Aptian-Albian times (i.e., the

ceous rifting events. Franz Josef Land and the

unconformably overlie Tithonian strata. The

Carolinefjellet Formation). The Albian deposits

areas to the west, including the northern part

Urals, Timan Range and intrabasinal highs

consist predominantly of clayey siltstones with

of Spitsbergen, were uplifted and supplied sedi-

became the main denudation areas, and allu-

rare lenses of bivalve coquina. In the upper part

ments to deltaic systems and sandy shelves to

vial sediments were deposited on their slopes.

of the succession glauconitic sands appear. The

the south. A basin developed, bounded to the

Within the intraplate depressions, alluvial-la-

succession of varying and alternating sand-

southwest by the Sørkapp-Horsund High.

custrine sands, silts and clays accumulated.

stone and claystone interbeds suggest a shal-

On Franz Josef Land, the Barremian-Albian

During the Aptian, the marine settings on

low-marine environment inﬂuenced by subtle

uplift was associated with volcanism. The ba-

the South Kara Shelf were replaced by near-

changes in sea-level and sediment supply. The

saltic sheets that formed during Aptian-Albian

shore marine and terrestrial depositional envi-

shallow-water nature of the sediments is evi-

time were more numerous than during Bar-

ronments. By the end of the Aptian, coal-bear-

dent from the occurrence of storm-inﬂuenced

remian times, and their thicknesses decreased

ing terrigenous sediments were deposited all

deposits. The deposits also contain relatively

from 20-30 m in the Barremian to 4-5 m in Ap-

over the South Kara Basin. In the central part

common marine fossils, including ammonites,

tian-Albian time. Intercalated with the basalt

of the inner basin (Leningradskaya and Rusa-

bivalves, marine phytoplankton and foramini-

sheets there are rare carbonaceous clayey lay-

novskaya areas), carbonaceous clays, siltstones

fers. Abundant terrestrial organic debris and

ers bearing large wood remains.

and sandstones were deposited in alluvial to la-

palynomorphs are also found in the succes-

The uplifted area also included Novaya

custrine environments. In the marginal parts

sion.

Zemlya, which was an area of erosion during

of the basin (Jamal Peninsula), alluvial sands

On the shelf, there appears to have been

the Albian. To the east, in the Kara Sea area,

and silts, with subordinate coals, dominated

relatively stable, marine depositional environ-

continental basins developed, with alluvial

the sedimentation (i.e., the Tonopchinskaya

ments, with open oceanic circulation and oxy-

plain, lakes and marshes, and in places with

Formation).

genated sea-bottom conditions. In the western-

coal deposits.

118

uplifted continental areas are approached.

At the beginning of Albian time, an exten-

most and deepest part of the Russian sector of

Farther to the south in the eastern part of the

sive transgression resulted in marine condi-

the shelf, the paleo-water depth reached up to

Barents Sea, an extensive coastal plain existed

tions occupying the entire South Kara Shelf.

400 m. In the deepest parts of the basins to the

in Mid Cretaceous time. This was characterised

Shallow-marine, predominantly clayey depos-

west, the water was probably even deeper. By

by changing depositional conditions, as shown

its with foraminifers, ammonites, bivalves and

Aptian-Albian times, the Barents Shelf was lo-

by alternations of marine and terrestrial set-

arthropods occur widely throughout the area

cated at approximately 50°N. Paleo-temperature

tings. In this area, the maximum regression was

(i.e., the Jarongskaya Formation). By the end of

measurements from isotopes in Early Aptian

reached in the Late Aptian, and a lacustrine-al-

the Albian, a regression had led to accumula-

bivalves on Spitsbergen are in the range 6.5-

luvial plain covered the whole of the East Bar-

tion of near-shore marine and deltaic deposits.

10.1°C.These temperatures are comparable with

ents Shelf including most of the Timan-Pechora

In contrast to the eastern areas, open-ma-

those reported from the Valanginian, and sup-

area. A new transgression started at the end of

rine shelf environments prevailed in the west-

port the view of an ice-house world with rela-

the Aptian, and reached its maximum in the

ern Barents Sea area. The western basins were

tively cool conditions at high palaeolatitudes.

Albian. Due to this change, a wide area of the

decoupled from the rest of the Barents Shelf

Barents Shelf was covered by sands and coal-

during the Early Cretaceous rifting events.

bearing silts, deposited in shallow-marine and

Due to the uplift in the north, large amounts

coastal-plain environments.

of sediment prograded from the northeastern

In the southern Barents Sea (i.e., the Mur-

areas into rapidly subsiding basins along the

manskaya and Severo-Murmanskaya areas),

western margin (i.e., the Harstad, Tromsø and

near-shore sands and coal-bearing silts were

Bjørnøya basins). Here, thick Aptian-Albian

replaced by shallow-marine clays with bivalves

successions accumulated, consisting predomi-

by the end of the Albian. In the central parts

nantly of shale, siltstone and minor sandstones

Albian

Albian 112.0—99.6 Ma

+ + +

+ +

68°0'0"N

70°0'0"N

72°0'0"N

74°0'0"N

76°0'0"N

78°0'0"N

30°0'0"E

40°0'0"E

50°0'0"E

Highland / Denudation area

Coast

Basalt

Shale

Marsh / Lacustrine

Shallow-water shelf

Sandstone, siltstone, clay

Marl

Periodically flooded area

Shelf

Sandstone, siltstone, clay, coal

Deep-water shelf

Siltstone, clay

Albian

119

Chapter 21 Eocene fossil leaves from Svalbard. Photo: Jan StenlĂ¸kk

Eocene Expanded hinterlands and shrunken basins

The Palaeogene succession at Pilarberget, Spitsbergen: Photo: Arvid NĂ¸ttvedt

Following the initial events linked to the Atlantic opening and general uplift, the eastern and central parts of the Barents â&#x20AC;&#x201C; Kara Region became a stable uplifted hinterland in the Eocene, and major sediment deposition was confined to the westernmost basins.

Wave-rippled bedding surface in Eocene sandstone deposits in the Central Basin on Spitsbergen. Photo: Jan Stenløkk

ajor rifting with continental break-

evidence remaining to help establish models

tances, indicating that the entire Sørvestsnaget

up commenced in the Late Creta-

for the Eocene paleogeography of the Barents

Basin was the site of deposition of sandy grav-

ceous along the North Atlantic rift

Sea platform and the Kara Sea.

ity ﬂows.

and in the Amundsen Basin to the north. As a

Due to the above-mentioned decoupling of

Palaeocene and Lower Eocene marine mud-

result of this rifting, a dextral stress ﬁeld was

the Barents Shelf from the areas on the other

stones are present in the Hammerfest Basin and

set up along the Senja-Hornsund lineament,

side of the de Geer Zone, the major eastern

western parts of the Nordkapp Basin, resting

and during the Palaeogene, this mega-fracture

and northern parts of the shelf were uplifted,

unconformably on the Cretaceous succession

acted as a relay zone between the spreading

but the basins of the westernmost Barents

with a marked hiatus. However, the Cenozoic

centres. The compressional component of the

Shelf continued to subside and received sig-

is entirely absent below the base of the Quater-

movements along the Hornsund Fault Zone,

niﬁcant amounts of sediment. The Harstad Ba-

nary in surrounding platform areas such as the

between the Svalbard region and North Green-

sin, Tromsø Basin, Sørvestsnaget Basin, Vest-

Finnmark and Bjarmeland platforms and parts

land, is manifested by the Fold- and Thust-Belt

bakken Volcanic Province and the areas west

of the Loppa High, as well as in the northern

on Svalbard. Sea-ﬂoor spreading began in the

of the Knølegga and Hornsund Fault Zones,

parts of the Barents Sea.

Norwegian-Greenland Sea south of the Green-

were principal areas of clastic deposition. Large

On Svalbard, western Spitsbergen was the

land-Senja Fracture Zone in the Early Eocene.

volumes of sediment derived from the newly

site of the Spitsbergen Orogeny. The orogeny

Signiﬁcant reorganisation of the spreading pat-

uplifted areas of the shelf were deposited here

itself took place in the Palaeocene, but it set the

terns occurred in the Mid Eocene, and spread-

during Eocene times.

scene for the subsequent Eocene deposition in

ing expanded farther north to the southern limit of the Hornsund Fault Zone.

122

Fossil cone preserved in Eocene sandstone, Svalbard. Photo: Jan Stenløkk

Whilst the Palaeocene record is entirely

the foreland basin of the mountain range, com-

made up of grey to olive-coloured claystones,

monly referred to as the Spitsbergen Central

Little is known about Eocene palaeogeogra-

the Eocene succession reﬂects episodes of con-

Basin. During the Eocene, the Central Basin

phy in the Pechora and Kara seas and eastern

siderably more active clastic deposition. Basi-

was a marine embayment apparently linking

parts of the Barents Sea. These areas probably

nal blocky sandstones of gravity ﬂow origin are

up with the oceanic conditions in the western

constituted a tectonically stable epicontinen-

encountered in drillcores in the central parts of

Tertiary basins. As in the Sørvestsnaget Basin

tal mega-region, and were either uplifted con-

the Sørvestsnaget Basin. Furthermore, Eocene

in the south, the Eocene was also the major

tinental hinterlands or shallow-marine seas

gas-bearing sandstones have been recorded on

epoch of active deposition in the Spitsbergen

with very limited net deposition. Sediments

the northwestern margin of the Sørvestsnaget

Central Basin where siliciclastics sediments

that may have been deposited, were subse-

Basin, probably deposited in upper slope to out-

prograded in from the orogenically elevated

quently removed due to later Neogene uplift

er-shelf settings. The seismic signature of the

western margin.

and erosion. Consequently, there is very little

sandstones can be extrapolated over large dis-

Eocene

Eocene 55.8—33.9 Ma

78°0'0"N 76°0'0"N 74°0'0"N 72°0'0"N 70°0'0"N 68°0'0"N

30°0'0"E

40°0'0"E

50°0'0"E

Highland / Denudation areas

Shallow-water shelf

Clays, sandstones, siltstones

Lacustrine / Fluvial plains

Shelf

Siltstones, clay

Marsh

Deep-water shelf

Sandstones, siltstones, clays Sandstones, silltstones, clays, coal

Eocene

123

Chapter 22

Late Neogene uplift and glaciations In the Neogene, large-scale plate movements caused uplift and erosion along the western Barents Shelf. During the Late Pliocene and Pleistocene, the geological development of the Barents Sea region was largely controlled by Northern Hemisphere glaciations. The entire Barents Shelf was eroded and large amounts of sediment were shed into major, submarine, depositional fans along the western margin.

ver the Barents Shelf there is a major

transitional growth phase lasting from 2.4 Ma

unconformity between the Mesozoic-

to about 1.0 Ma, the ice sheet expanded towards

Tertiary strata and overlying glacial

the southern Barents Sea and also reached the

deposits, marking the onset of the Northern

northwestern Kara Sea. During this period,

Hemisphere glaciations in the Late Pliocene.

the supply of sediments from the Siberian riv-

During the Late Pliocene-Pleistocene, the en-

ers into the Barents Sea decreased, while the

tire Barents Shelf was uplifted and eroded

growth rate of the sedimentary wedge along

and large amounts of sediment were shed into

the western shelf margin increased. The third

major, submarine, depositional depocentres

phase began at about 1.0 Ma with the exten-

along the western margin. Particularly large

sive glaciation in the Barents Sea and major

accumulations are found in the trough mouth

glacial expansion in the circum-Arctic region.

fans (Bjørnøya and Storfjorden fans) that con-

An intensiﬁcation of glaciation and a shift to a

tain up to 4 km-thick packages of glacigenic

dominant 100 000 year cyclicity in ice-volume

sediments, including glacimarine debris-ﬂow

ﬂuctuations is evident from the increased ﬂux-

deposits of 2000 km³, with run-out distances of

es of ice-rafted deposits and from the oxygen

up to 200 km. This proliﬁc succession resulted

isotope records. From this time and onwards,

from repeated glaciations and subsequent pe-

there were repeated ice withdrawals and new

riods of isostatic uplift. Maximum uplift and

ice-sheet advances to the shelf edge. There

erosion took place in the northern platform

is evidence that

areas and around Svalbard, where 2-3 km of

formed at the time of major terminations of the

sediments have been removed. To the south,

ice-sheets, and these suggest that at least ﬁve

in the Hammerfest and Nordkapp basins and

or six shelf-edge glaciations took place over the

on the Loppa High, the amount of uplift and

past 800 000 years in the Barents Sea.

massive melt-water pulses

erosion was less, generally no more than 2 km. Large amounts of Neogene outer shelf to slope sediments have been penetrated in wellbores in the Vestbakken Volcanic Province and in the Sørvestsnaget Basin. Due to the Neogene uplift and erosion, Neogene deposits are of limited extent in the Eastern Barents Sea region. On Franz Josef Land, Neogene shallow-marine sediments of presumed Late Pliocene age are restricted to a 14 km² rectangular area on Hoﬀman Island. The sedimentary rocks show signs of post-depositional, small-scale folding which is probably associated with late uplift. Possible MiddleUpper Pliocene deposits are also preserved in the deeper basins in the Eastern Barents Sea area. In the South Barents Basin, the package of unconsolidated Cenozoic sediments show seismic velocities ranging from 1.5 to1.8km/s. Pleistocene marine clays of variable thickness are widely distributed on the entire shelf. Generally, the Late Pliocene to Pleistocene glaciation history of the Barents Sea region can be divided into three major phases of ice growth. The initial phase started at approximately 3.6 Ma and lasted to about 2.6 Ma. During this time, the glaciers covered the mountainous regions and reached the coastline and shelf edge in the northern Barents Sea during short periods of intense glaciation. In the following

126

Late Neogene uplift and glaciations

Schematic model of the lateral ice extension in the Barents Sea region during Late Pliocene and Pleistocene time. Black stippled lines indicate the maximum extent of the ice-sheet, white transparent polygons indicate the minimum ice extent. A) Phase 1 at approximately 3.5-2.4 Ma, B) Phase 2 at approximately 2.4-1.0 Ma, C) Phase 3 at approximately 1.0 Ma and later Pleistocene time. It is important to note that within each of the three phases, glaciers have fluctuated between being almost completely absent to times when they reached their respective maximum extents.

Photo: Bjarne Riesto, edelpix Late Neogene uplift and glaciations

127

Acknowledgements We would like to thank several organizations and individuals for their kind support through the GeoBaSe project and contributions to this Atlas. Financial support to the GeoBaSe project has been provided by the Geological Survey of Norway (NGU), A.P. Karpinsky Russian Geological Research Institute (VSEGEI), StatoilHydro and the Petromaks program of the Norwegian Research Council. Special thanks are due the Erik Henriksen (StatoilHydro), Vidar B. Larsen (StatoilHydro, until 2007), Else Ormaasen (NPD) and Andrey F. Morozov (Roznedra) for their participation in the Steering Committee of the GeoBaSe project. Data acquisition and interpretation in individual areas, which have been integrated in this atlas, have been funded by diﬀerent industry partners over the years and in cooperation with diﬀerent institutes, too numerous to list all here. Winfried Dallmann, Ivar Midtkandal, Atle Mørk, Hans-Arne Nakrem, Arvid Nøttvedt, Jan Stenløkk and Hermann M. Weiss kindly provided photos from Svalbard. Ron Hackney and David Roberts contributed with useful comments and assisted in improving the English language. Jochen Knies provided the ice extension maps and gave useful comments on chapter 22. We are indebted to them all.

128

Acknowledgements

Literature – References Alsgaard, P.C. 1993. Eastern Barents Sea Late Palaeozoic setting and potential source rocks. In Vorren, T.O. et al. (Eds.), Arctic Geology and Petroleum Potential. NPF Special Publication 2, 405-418. Andreassen, K., Nilssen, L.C., Rafaelsen, B. & Kuilman, I. 2004. Three-dimensional seismic data from the Barents Sea margin reveal evidence of past ice streams and their dynamics. Geology, 32, 729-732. Andreassen, K., Ødegaard, C. & Rafaelsen, B. 2007. Imprints of former ice streams, imaged and interpreted using industry 3D seismic data from the south-western Barents Sea. In Davies, R.J., Posamentier, H.W., Wood, L.J. & Cartwrigh, J.A. (eds.), Seismic Geomorphology: Applications to Hydrocarbon Exploration and Production. Geological Society of London Special Publication, 151-169. Andreeva, I.A., Bondarev, V.I., Krasikov, E.M., Patrunov, D.K. & Tscekoldin R.S. 1979. Geological structure of Schmidt Peninsula (Northern Island of Novaya Zemlya. In Bondarev, V.I. (Ed.), Geology and Stratigraphy of Novaya Zemliya, NIIGA Publishing House, Leningrad, 18-37. Aplonov, S.V., Shmelev, G.B., Krasnov, D.K. 1996. Geodynamics of the Barents-Kara shelf (based on geophysical data). Geotectonica 4, 58-76. (In Russian). Bäckström, S.A. & Nagy, J. 1980. Depositional history and fauna of a Jurassic phosphorite conglomerate (the Brentskardhaugen Bed) in Spitsbergen. Norsk Polarinstitutt Skrifter, 183-1-61. Barrére, C., Ebbing, J. & Gernigon, L. 2009. Offshore prolongation of Caledonian structures and basement characterisation in the western Barents Sea from geophysical modelling Tectonophysics, 470, 71-88. Basov, V., Nikitenko, B. & Kupriyanova, N. 2008. Lower and Middle Jurassic foraminiferal and ostracod biostratigraphy of the eastern Barents Sea and correlation with northern Siberia. Norwegian Journal of Geology 88-259-266. Bergan, M. & Knarud, R., 1993. Apparent changes in clastic mineralogy of the Triassic-Jurassic succession, Norwegian Barents Sea: possible implications for palaeodrainage and subsidence. In: Vorre, T.O. et al. (Eds.), Arctic Geology and Petroleum Potential. NPF Special Publication 2, 481-493. Bergh, S.G. & Grogan, P. 2003. Tertiary structure of the Sørkapp-Hornsund region, south Spitsbergen, and implications for the offshore extension of the fold-thrustbelt. Norwegian Journal of Geology 83, 43-60. Birkenmajer, K. 1980. Jurassic-Cretaceous succession at Agardhbukta, east Spitsbergen. Studia Geologica Polonica, 66, 35-52. Birkenmajer, K., Pugaczewska, H. & Wierzbowski, A. 1982. The Janusfjellet Formation (Jurassic – Lower Cretaceous) at Myklegardfjellet, East Spitsbergen. Palaeontlogica Polinica, 43, 107-140. Blendinger, W., Bowlin, B., Zijp, F.R., Darke, G. & Ekroll, M. 1997. Carbonate buildup flank deposits: an example from the Permian (Barents Sea, northern Norway) challenges classical facies models. Sedimentary Geology, 112, 89–103.

Blomeier, D.,Wisshak, M., Joachimski, M., Freiwald, F. & Volohonsky, E. 2003. Calcareous, alluvial and lacustrine deposits in the Old Red Sandstone of central north Spitsbergen (Wood Bay Formation, Early Devonian). Norwegian Journal of Geology, 83, 281-298.

Colpaert, A., Pickard, N., Mienert, J., Henriksen, L.B., Rafaelsen, B. & Andreassen, K. 2007. 3D seismic analysis of an Upper Palaeozoic carbonate succession of the Eastern Finnmark Platform area, Norwegian Barents Sea. Sedimentary Geology, 197, 79-98.

Breivik, A.J., Gudlaugsson, S.T. & Faleide, J.I. 1995. Ottar-Basin, SW Barents-Sea - a Major Upper Paleozoic Rift Basin Containing Large Volumes of Deeply Buried Salt. Basin Research, 7, 299-312.

Corfu, F., Roberts, R.J., Torsvik, T.H., Ashwal, L.D. & Ramsay, D.M. 2007. Peri-Gondwanan elements in the Caledonian Nappes of Finnmark, Northern Norway: Implications for the paleogeographic framework of the Scandinavian Caledonides. American Journal of Science, 307, 434-458.

Breivik, A.J., Faleide, J.I. & Gudlaugsson, S.T. 1998. Southwestern Barents Sea margin: late Mesozoic sedimentary basins and crustal extension. Tectonophysics 293, 21-44. Breivik, A.J., Mjelde, R., Grogan, P., Shimamura, H., Murai, Y., Nishimura, Y. & Kuwano, A. 2002. A possible Caledonide arm through the Barents Sea imaged by OBS data. Tectonophysics, 355, 67– 97.

Crane, K., Eldholm, O., Myhre, A. M. and Sundvor , E., 1982. Thermal implications for the evolution of the Spitsbergen transform fault. Tectonophysics, 89, 1-32. Crane, K., Foucher, J. P., Hobart, M., Myhre, A. M. and Ledouaran, S., 1988. Thermal evolution of the western Svalbard margin. Marine Geophysical Researches, 9, 165-194.

Breivik, A.J., Mjelde, R., Grogan, P., Shimamura, H., Murai, Y. & Nishimura, Y. 2005. Caledonide development offshore-onshore Svalbard based on ocean bottom seismometer, conventional seismic, and potential field data. Tectonophysics, 401, 79-117.

Cutbill, J.L. & Challinor, A. 1965. Revision of the stratigraphical scheme for the Carboniferous and Permian rocks of Spitsbergen and Bjørnøya. Geological Magazine, 102, 418-439.

Brekke, H., Sjulstad, H.I., Magnus, C. & Williams, R.W. 2001. Sedimentary environments offshore Norway – an overview. In Martinsen, O.J. & Dreyer, T. (Eds.), Sedimentary Environments Offshore Norway – Palaeozoic to Recent. NPF Special Publication 10, 211-232.

Dagys, A., Weitschat, W., Konstantinov, A. & Sobolev, E. 1993. Evolution of the boreal marine biota and biostratigraphy of the Middle/Upper Triassic boundary. Mitteilungen, Geologisch-Palaeontologisches Institut der Universitat Hamburg, 75, 193-209.

Brigaud, F., Vasseur, G. and Caillet, G., 1992. Thermal state in the north Viking Graben (North Sea) determined from oil exploration well data. Geophysics, 57, 69-88.

Dalland, A., 1975. The Mesozoic rocks of Andøya, Norhern Norway. NGU Bulletin 316, 271-287.

Bugge, T., Elvebakk, G., Fanavoll, S., Mangerud, G., Smelror, M., Weiss, H.M., Gjelberg, J., Kristensen, S.E. & Nilsen, K. 2002. Shallow stratigraphic drilling applied in hydrocarbon exploration of the Nordkapp Basin, Barents Sea. Marine and Petroleum Geology 19, 13-37. Bugge, T., Mangerud, G., Elvebakk, G., Mørk, A., Nilsson, I., Fanavoll, S. & Vigran, J.O. 2003. The Upper Palaezoic succession on the Finnmark Platform. Norsk Geologisk Tidsskrift, 75, 3-30. Buiter, S.J.H. & Torsvik, T.H. 2007. Horizontal movements in the eastern Barents Sea constained by numerical models and plate reconstructions. Geophysical Journal International, 171, 1376-1389. Bungum, H., Ritzmann, O., Maercklin, N., Faleide, J., Mooney, W.D. & Detweiler, S.T. 2005. Three-Dimensional Model for the Crust and Upper Mantle in the Barents Sea Region. EOS, 86, doi: 10.1029/2005EO160003. Butt, F.A., Elverhøi, A., Solheim, A. & Forsberg, C.F. 2000. Deciphering Late Cenozoic development of the western Svalbard Margin from ODP Site 986 results. Marine Geology, 169, 373-390. Colpaert, A., Henriksen, L.B. & Mienert, J. 2004. Recognition of Upper Palaeozoic carbonate build-up facies on 3D seismic data: an example from the Eastern Finnmarl Platform, Nowegian Barents Sea. In Smelror, M. & Bugge, T.(Eds.), Arctic Geology, Hydrocarbon Resources and Environmental Challenges, Abstracts and Proccedings of the Geological Society of Norway, 2, 21-23.

Dalland, A., Worsley, D. & Ofstad, K. 1988. A lithostratigraphic sheme for the Mesozoic and Cenozoic succession offshore mid- and northern Norway. Norwegian Petroleum Directorate Bulletin 4, 65 p. Dallmann, W.K. (Ed.) 1999. Lithostratigraphic Lexicon of Svalbard. Norsk Polarstitutt, Tromsø, 318 p. Daragan-Suschova, L.A., Pavlenkin, A.D., Poselov, V.A., Murzin, R.R., Daragan-Suschov, Ju.I. 2000. Geological history of the Barents-Kara Region resulted from integration of regional geologic and geophysical data. In: G.P. Avetisov, G.P., Pogrebitsky, Ju.E. (Eds.), Geologic and geophysical characteristics of the Arctic Region lithosphere. VNIIOkeangeologia Publishing House, vyp. 3, St. Petersburg, 145-160. (In Russian). Demongodin, L., Vasseur, G. and Brigaud, F., 1993: Anisotropy of thermal conductivity in clayey formations. In A.G. Doré et. al. (Eds.), Basin Modelling: Advances and Applications. Norwegian Petroleum Society Special Publications. No 3, 209-217. Dengo, C.A. & Røssland, K.G. 1992. Extensional tectonic history of the Western Barents Sea. In Larsen, R.M. et al. (Eds.), Structural and Tectonical Modelling and its Application to Petroleum Geology. NPF Special Publication, Elsevier, Amsterdam, 91–107. Dibner, V.D. 1998. Geology of Franz Josef Land. Norsk Polarinstitutt Meddelelse 146, 190 p. Ditchfield, P.W. 1997. High northern palaeolatitude Jurassic-Cretaceous palaeotemperature variation: new data from Kong Karls Land, Svalbard. Palaeogeography, Palaeoclimatology, Palaeoecology, 130, 163-175.

Literature - References

129

Dodin, D.A. & Surkov, V.S. 2002. The Russian Arctic: geological history, mineragenesis, environmental geology. VNIIOkeangeologia, 960 p. (In Russian). Doré, A.G. 1991. The structural foundation and evolution of Mesozoic seaways between Europe and the Arctic, Palaeogeography, Palaeoclimatology, Palaeoecology, 87, 441–492. Doré, A.G., 1995. Barents Sea Geology, Petroleum Resources and Commercial Potential. Arctic, 48, 207-221. Doyle, P. & Kelly, S.R.A. 1988. The Jurassic and Cretaceous belemnites of Kong Karls Land. Norsk Polarinstitutt Skrifter, 189, 77 pp. Dypvik, H. 1980. The sedimentology of the Janusfjellet Formation, Central Spitsbergen (sassenfjorden and Agardhfjellet areas). Norsk Polarinstitutt Skrifter, 172, 97-134. Dypvik, H. 1985. Jurassic and Cretaceous black shales of the Janusfjellet Formation, Svalbard, Norway. Sedimentary Geology, 41, 235-248. Dypvik, H. 1992. Sedimentary rhythms in the Jurassic and Cretaceous of Svalbard. Geological Magazine, 129, 93-99. Dypvik, H., Nagy, J., Eikeland, T.A., Backer-Owe, K. & Johansen, H. 1991. Depositional conditions of the Bathonian to Hauterivian Janusfjellet Subgroup, Spitsbergen. Sedimentary Geology, 72, 55-78. Dypvik, H., Gudlaugsson, S.T., Tsikalas, F., Attrep, M., Ferrell, R.E., Krinsley, D.H., Mørk, A., Faleide, J.I. & Nagy, J. 1996. Mjølnir structure: An impact crater in the Barents Sea. Geology, 24, 779-782. Dypvik, H., Mørk, A., Smelror, M., Sandbakken, P.T., Tsikalas, F., Vigran, J.O., Bahiru, G.M. & Weiss, H. 2004. Impact breccias and ejecta from the Mjølnir Crater in the Barents Sea – The Ragnarrok Formation and the Sindre Bed. Norwegian Journal of Geology, 84, 143-167. Ebbing, J., Braitenberg, C., Wienecke, S. 2007. Insights into the lithospheric structure and tectonic setting of the Barents Sea region from isostatic considerations. Geophysical Journal International, 171, 1390-1403. Edwards, M.B. 1976. Depositional environments in Lower Cretaceous regressive sediments, Kikutodden, Sørkapp Land, Svalbard. Norsk Polarinstitutt Årbok 1974, 35-50. Ehrenberg, S.N., Nielsen, E.B., Svånå, T.A. & Stemmerik L. 1998. Depositional evolution of the Finnmark carbonate platform, Barents Sea: results from wells 7128/6-1 and 7128/4-1. Norsk Geologisk Tidsskrift, 78, 185–224. Ehrenberg, S.N.,Nielsen, E.B., Svånå, T.A. & Stemmerik L. 1998. Diagenesis and reservoir quality of the Finnmark carbonate platform, Barents Sea: results from wells 7128/6-1 and 7128/4-1. Norsk Geologisk Tidsskrift, 78, 225–252. Ehrenberg, S.N., Pickard, N.A.H., Svånå, T.A., Nilsson, I. & Davydov, V.I. 2000. Sequence stratigraphy of the inner Finnmark carbonate platform (Carboniferous-Permian), Barents Sea – correlation between well 7128/6-1 and the shallow IKU cores. Norsk Geologisk Tidsskrift, 80, 129–162.

130

Literature - References

Ehrenberg, S.N., Pickard, N.A.H., Henriksen, L.B., Svånå, T.A., Gutteridge,P. & McDonald, D. 2001. A depositional and sequence stratigraphic model for cold-water, spiculitic strata based on the Kapp Starostin Formation (Permian) of Spitsbergen and equivalent deposits from the Barents Sea. American Association of Petroleum Geologists Bulletin, 85, 2061–2087. Eidvin, T., Jansen, E. & Riis, F. 1993. Chronology of Tertiary fan deposits off the western Barents Sea: Implications for the uplift and erosion history of the Barents Shelf. Marine Geology, 112, 109-131. Eidvin, T., Goll, R.M., Grogan, P., Smelror, M. & Ulleberg, K. 1998. The Pleistocene to Middle Eocene stratigraphy and geological evolution of the western Barents Sea continental margin at well site 7316/5-1 (Bjørnøya West area). Norsk Geologisk Tidsskrift, 78, 99-123. Eliassen, A. & Talbot, M.R. 2003. Sedimentary facies and depositional history of the mid-Carboniferous Minkinfjellet Formation, Central Spitsbergen, Svalbard. Norwegian Journal of Geology, 83, 299-318. Eldholm, O., Sundvor, E., Vogt, P. R., Hjelstuen, B. O., Crane, K., Nilsen, A. K. and Gladzenko, T. P., 1999. SW Barents Sea continental margin heat flow and Håkon Mosby Mud Volcano. Geo-Marine Letters, 19, 29-37 Elvebakk, G., Hunt, D.W. & Stemmerik, L. 2002. From isolated buildups to buildup mosaics: 3D seismic sheds new light on Upper Carboniferous – Permian fault controlled carbonate buildups, Norwegian Barents Sea. Sedimentary Geology, 152, 7–17. Fairchild, I.J. 1982. The Orustdalen Formation on Brøggerhalvøya, Svalbard: A fan delta complex of Dinantian/Namurian age. Polar Research, 1, 17. Faleide, J.I., Vågnes, E. & Gudlaugsson, S.T. 1993. Late Mesozoic – Cenozoic evolution of the southwestern Barents Sea. In Parker, J.R. (Ed.), Petroleum geology of the Northwest Europe: Proceedings of the fourth conference. Geological Society of London, 933-950. Faleide, J.I., Solheim, A., Fiedler, A., Hjelstuen, B.O., Andersen, E. & Vanneste, K. 1996. Late Cenozoic evolution of the western Barents Sea-Svalbard continental margin. Global and Planetary Change, 12, 53-74. Faleide, J.I., Tsikalas, F., Breivik, A.J., Mjelde, R., Ritzman, O., Engen, Ø., Wilson, J. & Eldholm, O. 2008. Structure and evolution of the continental margin off Norway and the Barents Sea. Episodes, 31, 82-91. Federovsky, Ju F., Tronov, Ju A., Vinnikovsky, V.S., Evsukov, V.T., Tanygin, I.A., Zalivchiy, O.A. 1993. Significant results from prospecting/exploration works in the Barents-Kara Region. Geodynamic and Oil-Gas Potential in the Arctic Region. Nedra, Moscow, 15-19. (In Russian). Fichler, C., Rundovde, E., Johansen, S. & Sæter, B.M. 1997. Barents Sea tectonic structures visualized by ERS1 satellite gravity with indications of an offshore Baikalian trend. First Break, 15, 355-362. Gabrielsen, R.H., Færseth, R.R., Jensen, L.N., Kalheim, J.E. & Riis, F. 1990. Structural elements of the Norwegian continental shelf. Part 1, The Barents Sea region. Norwegian Petroleum Directorate Bulletin, 6, 33 p. Gautier, D., Bird, K. J., Charpentier, R., Grantz, A., Houseknecht, D.W., Klett, T.R., Moore, Pitman, J.

K., Schenk, J., Schuenemeyer, J.H., Sørensen, K., Tennyson, M. E., Valin, Z.C., Wandrey, C.J. 2009. Assessment of Undiscovered Oil and Gas in the Arctic. Science, 324, 1175-1179. Gavrilov, V.P. (Ed.), 1993. Geodynamics and hydrocarbon potential of Arctic Nedra, Moscow, 324 p. (In Russian). Gee, D.G. & Pease, V. 2004. The Neoproterozoic Timanide Orogen of eastern Baltica: introduction. In Gee, D.G. and Pease, V. (Eds.), Timanides –Neoproterozoic Orogeny Along the Eastern Margin of Baltica. Geological Society, London Memoirs, 1-4. Gee, D.G., Fossen, H., Henriksen, N.& Higgins, A.K. 2008. From the early Paleozoic platforms of Baltica and Laurentia to the Caledonide orogen of Scandinavia and Greenland. Episodes, 31, 44-51. Gernigon, L., Ringenbach, J.C., Planke, S., Le Gall, B. & Jonquet-Kolstø, H. 2003. Extension, crustal structure and magmatism at the outer Vøring Basin, Norwegian margin. Journal of the Geological Society, 160, 197-208. Gernigon, L., Marello, L., Mogaard, J.O., Werner, S.C. & Skilbrei, J.R. 2007. Barents Sea Aeromagnetic Survey BAS - 06: Acquisition-processing report and preliminary interpretation. NGU Report 2007.035, Geological Survey of Norway, Trondheim. Gjelberg, J.G. 1981. Upper Devonian (Famennian) – Middle Carboniferous succession of Bjørnøya. A study of ancient alluvial and coastal marine sedimentation. Norsk Polarinstitutt Skrifter, 174, 1-67. Gjelberg, J.G. & Steel, R.J. 1981. An outline of LowerMiddle Carboniferoues sedimentation on Svalbard: effects of climate, tectonic and sea level changes in rift basin sequences. In Kerr, J.W. & Ferguson, A.J. (Eds.), Geology of the North Atlantic Borderlands. Canadian Society of Petroleum Geologists Memoir, 7, 543-561 Gjelberg, J. and Steel, R.J. 1995. Helvetiafjellet Formation (Barremian-Aptian), Spitsbergen: characteristics of a transgressive succession. In Steel, R.J. et al. (Eds.), Sequence Stratigraphy on the Northwest European Margin. NPF Special Publication, 5, 571-593. Gjelsvik, T. & Ilyes, R. 1991. Distribution of Late Silurian (?) and Early Devonian grey-green sandstone in the Liefdefjorden-Bockfjorden area, Spitsbergen. Polar Research, 9, 77-87. Gobett, D.J. 1963. Carboniferous and Permian brachiopods of Svalbard. Norsk Polarinstitutt Skrifter, 127, 1-201. Goutorbe, B., Lucazeau, F., and Bonneville, A., 2007. Comparison of several BHT correction methods: a case study on an Australian data set. Geophysical Journal International, 170, 913-922. Gramberg, I.S. (Ed.) 1988. The Barents Shelf Plate. In Alekin et al. (Eds), “Nedra”, Leningrad, 263 p. (In Russian). Gramberg, I.S., 1997. Barents Sea paleorift in PermoTriassic and its bearing for the hydrocarbon potential of the Barents-Kara Plate. Doklady RAN, 352, (6), 789791. (In Russian). Gramberg I.S. & Ushakov, V.I (Eds) 2000. Geological structure and metallogeny. VNIIOkeangeologia, St.Petersburg, 187 p.

Gramberg, I.S., Glebovsky,V. Y., Grikuro, G.E., Ivanov, V.L., Korago, E.A., Kos’ko, M.K., Maschenkov, S.P., Piskarev, A.L., Pogrebitsky, Y.E., Shipelkevitch, Y. V. & Suprunenko, O.I. 2001. Eurasian Artic Margin: Earth Science Problems and Research Challenges. Polarforschung, 69, 3-15. Gramberg, I.S, Ivanov, V.L., Pogrebitsky, Ju.E. (Eds.), 2004. Geology and mineral deposits of Russia. Book 5. Arctic seas. VSEGEI Publishing House, St. Petersburg, VNIIOkeangeology), 468 p. (In Russian). Grogan, P., Nyberg, K., Fotland, B., Myklebust, R., Dahlgren, S. & Riis, F. 2000. Cretaceous Mamatism South and East of Svalbard: Evidence from Seismic Reflection ad Magnetic Data. Polarforschung, 68, 25-24. Grogan, P., Østvedt-Ghazi, A.M., Larssen, G.B., Fotland, B., Nyberg, K., Dahlgren, S. & Eidvin, T. 1999. Structural elements and petroleum geology of the northern Barents Sea. In Fleet, A.J. & Boldy, S.A.R. (Eds.), Petroleum geology og North-West Europe and Global Perspectives – Proceedings of the 6th Petroleum Geology Conference. Geological Society of London, 247-259. Grøsfjeld, K. 1992. Palynological age constraints on the base of the Helvetiafjellet Formation (Barremian) on Spitsbergen. Polar Research, 11, 11-19. Gudlaugsson, S.T., Faleide, J.I., Johansen, S.E. & Breivik, A.J. 1998. Late Paleozoic structural development of the south-western Barents Sea. Marine and Petroleum Geology 15, 73-102. Gurari, F.G., 1981. Domanikites and their oil and gas content. Soviet Geology., 11, 3-12. ( In Russian). Gustavsen, F.B., Dypvik, H. & Solheim, A. 1997. Shallow geology of the Northern Barents Sea: Implications for Petroleum Potential. AAPG Bulletin, 81, 1827-1842. Harland, W.B. 1997. The Geology of Svalbard. Geological Society of London. Memoir, 17, 521 p. Harland, W.B. & Dowdeswell, E.K. 1988. Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 176 p. Harland, W.B., 1997. The geology of Svalbard. Geological Society of London Memoir 17. Helland-Hansen, W. 1990. Sedimentation in Paleogene Forland Basin, Spitsbergen. AAPG Bulletin, 74, 260-272. Henriksen, E., Rafaelsen, B., Stoupakova, A. et al. 2007. Stratigaphy of the Barents-Kara region. In Brekke, H., Henricksen, S. & Haukdal, G. (Eds), The Arctic Conference Days. Abstract and Proceedings of the Geological Society of Norway, 2, p. 207. Ivanova, N.M. 1997. Prospective Palaeozoic reefs in the southern part of the Barents Sea Shelf. Petroleum Geoscience, 3, 153-160. Ivanova, N.M., Sakoulina, T.S., Roslov, Yu V. 2006. Deep seismic investigations across the Barents-Kara and Novozemlskiy Fold Belt (Arctic Shelf). Tectonophysics, 420, 123-140. Jensen, L.N. and Sørensen, K. 1992. Tectonic framework and halokinesis of the Nordkapp Basin. In Larsen, R.M., Brekke, H. Larsen B.T. & Talleraas E. (Eds.), Structural and Tectonic Modelling and its Ap-

plication to Petroleum Geology. NPF Special Publications 1, 109-120.

adjacent water areas. Scale 1:5 million. All-Russia Geological Research Institute.

Johansen, S.E., Ostisty, B.K., Birkeland, Ø., Federovsky, Y.F., Martirosjan, V.N., Bruun Christensen, O., Cheredeev, S.I., Ignatenko, E.A. & Margulis, L.S., 1993. Hydrocarbon potential in the Barents Sea region: play distribution and potential. In Vorren, T.O. et al. (Eds.), Arctic Geology and Petroleum Potential. NPF Special Publication 2, 273-320.

Lopatin, B.G., Pavlov, L.G., Orgo, V.V. & Shkarubo, S.I. 2001. Tectonic structure of Novaya Zemlya. Polarforschung, 69, 131-135.

Knies, J., Matthiessen, J., Vogt, C., Laberg, J.S., Hjelstuen, B.O., Smelror, M., Larsen, E., Andreassen, K., Eidvin, T. & Vorren, T.O. 2009. The Plio-Pleistocene glaciation of the Barents Sea-Svalbard region: a new model based on revised chronostratigraphy. Quaternary Science Reviews, 28, 812-829.

Løfaldli, M. & Thusu, B. 1979. Micropalaeontological studies of the Upper Jurassic and Lower Cretaceus of Andøya, northern Norway. Palaeontology, 22, 413-425.

Knutsen, S.-M. & Larsen, K.I. 1997. The late Mesozoic and Cenozoic evolution of the Sørvestsnaget Basin: A tectonostratigraphic mirror for regional events along the Southwestern Barents Sea Margin? Marine and Petroleum Geology, 14, 27-54. Korago, Eu.A., Kovaleva, G.N., Iljin, V.F., Pavlov, L.G. 1992. Tectonics and metallogeny of the Early Kimmerids in Novaya Zemlja. VNIIOkeangeologia, Nedra, Leningrad, 196 p. (In Russian). Korago, Eu.A., Timofeeva, T.N. 2005. Geology and magmatism of Novaya Zemlya (in the framework of geological history of the Barents-North Kara Region). VNIIOkeangeologia Publishing House, St.-Petersburg, 225 p. (In Russian). Kosteva, N.N. 2004. The sources of denudation for the Barents Sea Mesozoic sedimentary provinces. In: Smelror, M. & Bugge, T., Arctic Geology, Hydrocarbon Resources and Environmental Challenges, Abstracts and Proccedings of the Geological Society of Norway, 2 (2004), 74-75. Langrock, U. & Stein, R. 2004. Origin of marine petroleum source rocks from the Late Jurassic to Early Cretaceous Norwegian Greenland Seaway – evidence for stagnation and upwelling. Marine and Petroleum Geology, 21, 157-176. Larssen, G.B., Elvebakk, G., Henriksen, L.B., Kristensen, S.-E., Nilsson, I., Samuelsberg, T., Svanå, T.A., Stemmerik, L. & Worsley, D. 2005. Upper Paleozoic lithostratigraphy of the southern part of the Norwegian Barents Sea. NGU Bulletin, 444, 43 p. Leith, T.L., Weiss, H.M., Mørk, A., Århus, N., Elvebakk, G., Ebry, A.F., Brooks, P.W., Stewart, K.R., Pchelina, T.M., Bro, E.G., Verba, M.L., Danyushevskaya, A. & Borisov, A.V. 1992. Mesozoic hydrocarbon source-rocks of the Arctic region. In Vorren, T.O. et al. (eds.), Arctic Geology and Petroleum Potential. NPF Special Publication, 2, 1-25. Lindstrom, S. 2003. Carboniferous palynology of the Loppa High. Norwegian Journal of Geology, 83, 333349. Lipinski, M., Warning, B. & Brumsack, H.-J. 2003. Trace metal signatures of Jurassic/Cretaceous black shales from the Norwegian Shelf and Barents Sea. Palaeogeography, Palaeoclimatology, Palaeoecology, 190, 459-475. Litvinova, T.P. Trunin, A.A., Negrov, O.B., Dudnik, A.N., Zelenzky, D.S & Tselishceva, L.A. 2004. The map of the anomalous magnetic field of Russia and

Lowell, J.D. 1972. Spitsbergen Tertiary orogenetic belt and the Spitsbergen Fracture Zone. Geological Society of America Bulletin, 83, 3091-3102.

Lønøy, A. 1995. A Mid-Carboniferous, carbonate-dominated platform, Central Spitsbergen. Norsk Geologisk Tidsskrift, 75, 48-63. Løseth, H., Lippard, S. J., Sættem, J., Fanavoll, S., Fjerdingstad, V., Leith, T.L., Ritter, U., Smelror, M., and Stylta, Ø, 1992. Cenozoic uplift and erosion of the Barents Sea -evidence from the Svalis Dome area. In Vorren, T. O., Bergsaker, E., Dahl-Stamnes, O. A., Holter, E., Johansen, B., Lie, E. & Lund, T. B. (eds) Artic Geology and Petroleum Potential. Norwegian Petroleum Society Special Publication, 2, 643-664. Maher, H.D. Jr. 2001. Manifestations of the Cretaceous High Arctic Large Igneous Province in Svalbard. Journal of Geology, 109, 91-104. Mangerud, G. & Konieczny, R.M. 1993. Palynology of the Permian succession of Spitsbergen, Svalbard. Polar Research, 12, 65-93. Mangerud, J., Jansen, E. & Landvik, J.Y. 1996. Late Cenozoic history of the Scandinavian and Barents Sea ice sheet. Global and Planetary Change, 12, 11-26. Manum, S.B. & Throndsen, T. 1986. Age of Tertiary formations on Spitsbergen. Polar Research, 4, 103-131. Maschenkov, S.P. Glebovsky, V.Yu. & Zayonchek, A.V. 2001, New Digital Compilation of Russian Aeromagnetic and Gravity Data over the North Eurasian Shelf. Polarforschung, 69, 35-39. Midttømme, K., Roaldset, E., and Aagaard, P., 1997. Thermal conductivity of argillaceous sediments.n D.M. MacCann, M. Eddleston, P. Fenning & G.M. Reeves (Eds.), Modern geophysics in engineering geology, Geological Society Engineering Geology Special Publication, 12, 355-363. Murascov, L.G. & Mokin, J.I. 1979. Stratigraphic subdivision of the Devonian deposits of Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 249-261. Mutrux, J., Maher, H., Shuster, R. & Hays, T. 2008. Iron ooid beds of the Carolinefjellet Formation, Spitsbergen, Norway. Polar Research, 27, 28-43. Mutterlose, J. Brumsack, H., Flögel, Hay, W., Klein, C., Langrock, U., Lipinski, M., Ricken, W., Söding, Stein, R. & Swientek, O. 2003. The Greenland-Norwegian Seaway: A key area for understanding Late Jurassic to Early cretaceous paleoenvironments. Paleoceanography, 18, 1010, doi: 10.1029/2001PA000625, 2003. Mørk, A. & Elvebakk, G. 1999. Lithological description of subcropping Lower and Middle Triassic rocks from the Svalis Dome, Barents Sea. Polar Research, 18, 83-104.

Literature - References

131

Mørk, A. & Smelror, M. 2001. Correlation and NonCorrelation of High Order Circum-Arctic Mesozoic Sequences. Polarforschung, 69, 65-72.

Nakrem, H.A., Nilsson, I. & Mangerud, G. 1992. Permian biostratigraphy of Svalbard (Arctic Norway) – A review. International Geology Review, 34, 9333-959.

Parker, J.R. 1967. The Jurassic and Cretaceous sequence in Spitsbergen. Geological Magazine, 104, 487-505.

Mørk, A., Knarud, R. & Worsley, D. 1982. Depositional and diagenic environments of the Triassic and Lower Jurassic succession on Svalbard. In Embry, A.F. & Balkwill, H.R. (Eds.), Arctic Geology and Geophysics, Canadian Society of Petroleum Geologists Memoir, 8, 371-398.

Nakrem, H.A., Szaniawski, h. & Mørk, A. 2001. Permian-triassic scolecodonts and conodonts from the Svalis Dome, Central Barents Sea, Norway. Acta Palaeontologica Polonica, 46, 69-86.

Pelina, T.M. 1967. Stratigraphy and some characteristics of the composition of the Mesozoic sediments in southern and eastern regions of Vestspitsbergen. In Sokolev, V.N. (Ed.), Stratigraphy of Spitsbergen, 64-205, NIIGA, Leningard (In English tranl. 1977, The British Library Board).

Mørk, A., Embry, A.F. & Weitschat, W. 1989. Triassic transgressive-regressive cycles in the Sverdrup Basin, Svalbard and the Barents Shelf. In Collison, J.D. (Ed.), Correlation in Hydrocarbon Exploration. Norwegian Petroleum Society, Graham & Trotman, 113-130. Mørk, A., Vigran, J.O. & Hochuli, P.A. 1990. Geology and palynology of the Triassic succession of Bjørnøya. Polar Research, 8, 141-163. Mørk, M.B.E. 1999. Compositional variations and provenance of Triassic sandstones from the Barents Shelf. Journal of Sedimentary Research, 69, 690-710. Mørk, M.B.E. & Duncan, R.A. 1993. Late Pliocene basaltic volcanism on the western Barents Shelf margin – implications from petrology and 40Ar-39Ar dating of volcaniclastic debris from a shallow drill core. Norsk Geologisk Tidsskrift, 73, 209-225. Nagy, J. 1970. Ammonite faunas and stratigraphy of Lower Cretaceous (Albian) rocks in southern Spitsbergen. Norsk Polarinstitutt Skrifter, 152, 58 p. Nagy, J. 2005. Delta-influenced foraminiferal facies and sequence stratigraphy of Paleocene deposits in Spitsbergen. Palaeogeography, Palaeoclimatology, Palaeoecology, 222, 161-179. Nagy, J. & Basov, V.A. 1998. Revised foraminiferal taxa and biostratigraphy of Bathonian to Ryazanian deposits in Spitsbergen. Micropaleontology, 44, 217-255. Nagy, J. & Berge, S. 2008. Micropaleontological evidence of brackish water conditions during deposition of the Knorringfjellet Formation, Late Triassic—Early Jurassic, Spitsbergen. Polar Research, 27, 413-427. Nagy, J., Løfaldli, M., Backström, S.A. & Johansen, H. 1990. Agglutinated foraminiferal stratigraphy of Middle Jurassic to basal Cretaceous shales, Central Spitsbergen. In Hemleben, C. et al. (Eds.), Palecology, Biostratigraphy, Paleocanography and Taxonomy of Agglutinated Foraminifera. Kluwer Academic Press, 969-1015 Nagy, J., Kaminski, M.A., Johnsen, K. & Mitlehner, A.G. 1997. Foraminiferal, palynomorph, and diatom biostratigraphy and paleoenvironments of the Torsk Formation: A reference section for the PaleoceneEocene transition in the western Barents Sea. In Hass, H.C. & Kaminski, M.A. (Eds.), Contributions to the Micropaleontology and Paleoceanography of the Northern North Atlantic. Gryzbowski Foundation Special Publication, 5, 15-38. Nagy, J., Kaminski, M., Kuhnt, W. & Bremer, M.A. 2000. Agglutinated Foraminifera from Neritic to Bathyal Facies in the Palaeogene of Spitsbergen and the Barents Sea. In Hart, M.B., Kaminski, M.A. & Smart, C.W. (Eds.), Proceedings of the Fifth International workshop of Agglurinated Foraminifera. Gryzbowski Foundation Special Publication, 7, 333-361.

132

Literature - References

Nemec, W., Steel, R., Gjelberg, J., Collinson, J.D., Prestholm, E. & Øksneved, E.I. 1988. The anatomy of collapsed and re-established delta slope in the lower Cretaceous of Eastern Spitsbergen: gravitational sliding and sedimentation processes. AAPG Bulletin, 72, 454-476.

Pelina, T.M. 1986. The mineralogical criterions of palaeogeography of Mesozoic deposits of Spitsbergen. In Geology of the sedimentary cover of Spitsbergen archipelago. Leningard, Sevmorgeologia, 60-76 (In Russian).

Nikonov, N.I., Bogatzki, V.I. , Martynov, V.A. et al. 2000. The Timan-Pechora sedimentary Basin. Atlas of geological (litho-facies, structural, and paleogeographic) maps. Ukhta, Timan-Pechora Scientific Research Center, 64 sheets.

Pelina, T.M. & Korčinskaja, M.V. 2008. Palaeogeographic reconstructions of the Russian Boreal area and Svalbard during the Triassic. Polar Research, 27, 491-494.

Nilsen, K.T., Vendeville, B.C. & Johansen, J.T. 1995. Influence of Regional Tectonics on Halokinesis in the Nordkapp Basin, Barents Sea. In Jackson, M.P.A., Robert, D.G. and Snelson, S. (Eds.), Salt tectonics: a global perspective. AAPG Memoir 65, 413-436.

Petrov, O.V., Daragan-Suschova, L.A., Sobolev, N.N. & Daragan-Suschov Ju.I. 2005. Structure of the preJurassic basement of northern part of the West Siberian Plate. Regionalnaya Geologia I Metallogenia, 26, VSEGEI Publishing House, 153-169. (In Russian).

Nilsen, K.T., Hendriksen, E. & Larssen, G.B. 1993. Exploration of the Late Palaeozoic carbonates in the southern Barents Sea – a seismic stratigraphic study. In: Vorren, T.O. et al. (Eds.), Arctic Geology and Petroleum Potential. NPF Special Publication 2, 393-403.

Petrov, O.V., Sobolev, N.N., Koren, T.N., Vasiliev, V. & Petrov, E.O. 2007. Paleozoic and Mesozoic geodynamics and sedimentology in the East Barents Region. In Brekke, H., Henricksen, S. and Haukdal, G. (Eds), The Arctic Conference Days. Abstract and Proceedings of the Geological Society of Norway, 2, p. 54.

Nøttvedt, A., Cecchi, M., Gjelberg, J.G., Kristensen, S.E., Lønøy, A., Rasmussen, A., Rasmussen, E., Skott, P.H. & van Veen, P.M., 1993. Svalbard – Barents Sea correlation: a short review. In Vorren, T.O. et al. (Eds.), Arctic Geology and Petroleum Potential. NPF Special Publication 2, 363-375. Nøttvedt, A., Livbjerg, F., Midbøe, P. & Rasmussen, E. 1993. Hydrocarbon potential of the Central Spitsbergen Basin. In Vorren, T.O. et al. (Eds.), Arctic Geology and Petroleum Potential. NPF Special Publication 2, 333-361. Olaussen, S., Gloppen, T.G., Johannessen, E. & Dalland, A. 1984. Depositional and diagenesis of Jureassic reservoir sandstone in the eastern part of Troms I area. In Spencer, A.M. et al. (Eds.), Petroleum Geology of Northwest European Margin. Graham and Trotman, London, 61-80. O’Leary, N., White, N., Tull, S., Bashilov, V., Kuprin, V., Natapov, L., MacDonald, D. 2004. Evolution of the Timan-Pechora and South Barents Sea basins. Geological Magazine, 151, 141-160. Olesen, O., G., Gellein, J., Håbrekke, H., Kihle, O., Skilbrei, J.R. & Smethurst, M.A. 1997. Magnetic anomaly map, Norway and adjacent ocean areas. Scale 1:3 million. Geological Survey of Norway. Opepjohn, K., Brinkman, L., Gruwing, A. & Kerp, H. 2000. New data on the age of the uppermost ORS and the lowermost post-ORS strata in Dickson Land (Spitsbergen) and implications for the age of the Svalbardian deformation. In Friend, P.F. & Williams, B.P.J. (Eds.), New Perspectives on the Old Red Sandstone. Geological Society London Special Publication, 180, 603-609. Otto, S.C. & Bailey, R.J. 1995. Tectonic evolution of the northern Ural Orogen. Journal of the Geological Society of London, 152, 903-096.

Petrov, O.V., Sobolev, N.N., Koren, T.N., Vasiliev, V.E., Petrov, E.O., Larssen, G.B. & Smelror, M. 2008: Paleozoic and Early Mesozoic evolution of the East Barents and Kara Seas sedimentary basins. Norwegian Journal of Geology, 88, 227-234. Rafaelsen, B., Stoupakova, A., Nielsen, J.K. et al. 2004. Stratigraphy and facies of the Palaeozoic succession in the Barents Sea, Svalbard, Novaya Zemlya and Timan-Pechora region. In Brekke, H., Henriksen, S. and Haukdal, G. (Eds), The Arctic Conference Days. Abstract and Proceedings of the Geological Society of Norway, 2, 177-178. Rafaelsen, B., Elvebakk, G., Andreassen, K., Stemmerik, L., Colpaert, A & Samuelsberg, T. 2008: From detached to attached carbonate buildup complexes 3D seismic data from the Upper Palaeozoic, Finnmark Platform, southwestern Barents Sea. Sedimentary Geology, 206, 17-32. Roberts, D. 2003. The Scandinavian Caledonides: event chronology, palaeogeographic settings and likely, modern analogues. Tectonophysics, 365, 283-299. Roberts, D. & Lippard, S. 2005. Inferred Mesozoic faulting in Finnmark. Current status and offshore links. NGU Bulletin, 443, 55-60. Roberts, D. & Olovyanishnikov, V. 2004. Structural and tectonic development of the Timanide orogen. In Gee D. and Pease V. (Eds.), The Neoproterozoic Timanide Orogen of Eastern Baltica. Geological Society, London, Memoirs, 47-57. Rice, A.H.N. and Frank, W. 2003. The early Caledonian (Finnmarkian) event reassessed in Finnmark: 40 Ar/ 39 Ar cleavage age data from NW Varangerhalvoya, N. Norway. Tectonophysics, 374, 219-236.

Riis, F., Lundschien, B.A., Høy, T., Mørk, A. & Mørk, M.B.E. 2008. Evolution of the Triassic shelf in the northern Barents Sea Region. Polar Research, 27, 318338. Ritzmann, O., Maercklin, N., Faleide, J.I., Bungum, Mooney, W.D. & Detweiler, S.T. 2007. A three-dimensional geophysical model of the crust in the Barents Sea region: model construction and basement characterization. Geophysical Journal International, 170, 417–435. Ryseth, A., Augustson, Charnock., M., Haugerud, O., Knutsen, S.-M., Midbøe, P.S., Opsal, J.G. & Sundsbø, G. 2003. Cenozoic stratigraphy and evolution of the Sørvestsnaget Basin, southwestern Barents Sea. Norwegian Journal of Geology, 83, 107-130. Sakulina, T.S., Roslov, Yu. V. & Ivanova, N.M. 2003. Deep Seismic Investigations in the Barents and Kara Seas. Physics of the Solid Earth, 39, 438-452. Samuelsberg, T.J., Elvebakk, G. & Stemmerik, L. 2003. Late Palaeozoic evolution of the Finnmark Platform, southern Norwegian Barents Sea. Norwegian Journal of Geology, 83, 351-362. Schweitzer, H.-J. 1999. Die Devonfloren Spitzbergens. Palaeontographica, B 252, 1-122. Skilbrei, J.R. 1991. Interpretation of depth to the magnetic basement in the northern Barents Sea (south of Svalbard). Tectonophysics, 200, 127-141. Skilbrei, J.R. 1995. Aspects of the geology of the southwestern Barents Sea from aero-magnetic data. NGU Bulletin, 427, 64-67. Smelror, M. 1994. Jurassic stratigraphy of the western Barents Sea region: a review. Geobios, 17, 441-451. Smelror, M., Mørk, A., Monteil, E., Rutledge, D., Leereveld, H. 1998. The Klippfisk Formation - a lithostratigraphic unit of Lower Cretaceous platform carbonates on the Western Barents Shelf. Polar Research, 17, 181-202. Smelror, M., Mørk, M. B. E, Mørk, A., Løseth, H. & Weiss, H.M. 2001. Middle Jurassic-Lower Cretaceous transgressive-regressive sequences and facies distribution off Troms, northern Norway. In Martinsen, O.J. & Dreyer, T. (eds.), Sedimentary Environments Offshore Norway -Palaeozoic to Recent. NPF Special Publication,10, 211-232. Smelror, M., Kelly, S.R.A., Dypvik, H., Mørk, A., Nagy, J. & Tsikalas, F. 2001. Mjølnir (Barents Sea) meteorite impact ejecta offer a Volgian-Ryazanian boundary marker. Newsletter on Stratigraphy, 38, 129-140. Smith, D.G. 1975. The stratigraphy of Wilhelmøya and Hewaldfjellet, Svalbard. Geological Magazine, 112, 481-491. Smith, D.G., Harland, W.B., Hughes, N.F. & Pickton, C.A.G. 1976. The geology of Kong Karls Land, Svalbard. Geological Magazine, 113, 193-304. Sokolov, D. & Bodylevsky, W. 1931. Jura- und Kreidefaunen von Spitsbergen. Skrifter om Svalbard og Ishavet, 35, 151 p. Solheim, A., Mustatov, E. & Heintz, N. (Eds.) 1998. Geological aspects of Franz Josef Land and the north-

ernmost Barents Sea – the northern Barents Sea geotraverse. Norsk Polarinstitutt Meddelelse, 151, 120 p. Sollid, K., Ashton, N., Gytri, S.R., Henriksen, L.B., Larssen, G.B., Laursen, I. & Rønning, K. 2004. Triassic paleoenvironments, southwestern Barents Sea. New plays emerging from 3D seismic facies mapping. In Smelror, M. & Bugge, T.(Eds.), Arctic Geology, Hydrocarbon Resources and Environmental Challenges, Abstracts and Proccedings of the Geological Society of Norway, 2, 168-170. Spath, L.F. 1921. On ammonites from Spitsbergen. Geological Magazine, 58, 297-305, 347-356. Steel, R. & Worsley, D. 1984. Svalbard’s post-Caledonian strata – an atlas of sedimentological patterns and palaeogeographic evolution. In Spencer, A.M. et al. (Eds.), Habitat of hydrocarbons on the Norwegian continental margin. Norwegian Petroleum Society, Graham & Trotman, 109-135. Stemmerik, L. 2000. Late Palaezoic evolution of the North Atlantic margin of Pangea. Palaeogeography, Palaeoclimatology, Palaeoecology, 161, 95-126. Stemmerik, L. & Worsley, D. 1995. Permian history of the Barents Shelf area. In: Scholl, P.A., Peryt, T.M. & Ulmer-Scholle, D.S. (Eds.), Permian of northern Pangaea, vol. 2: Sedimentary basins and economic resources, Springer Verlag, Berlin, 81-97. Stemmerik, L. & Worsley, D. 2005. 30 years on – Arctic Upper Palaeozoic stratigraphy, depositional evolution and hydrocarbon prospectivity. Norwegian Journal of Geology, 85, 151-168. Stemmerik, L., Elvebakk, G., Nilsson, I. & Olaussen, S. 1998. Comparison of upper Bashkirian – upper Moscovian high frequency sequences between Bjørnøya and the Loppa High, western Barents Sea. In Gradsetin, F.M. et al. (eds.), Sequence Stratigraphy – concepts and applications. NPF Publication, 8, 215-227. Stemmerik, L., Larson, P.A., Larssen, G.B., Mørk, A. & Simonsen, B.T. 1994. Depositional evolution of Lower Permian Palaeoaplysina build-ups, Kapp Duner Formation, Bjørnøya, Arctic Norway. Sedimentary Geology ,92, 161-174. Sundvor, E., 1986. Heat Flow Measurements on the Western Svalbard Margin. University of Bergen. Seismological Observatory, Internal Report. Sundvor, E., Myhre, A. M. and Eldholm, O., 1989. Heat Flow Measurements on Norwegian Continental Margin during the Flunorge Project. University of Bergen, Seismological Observatory, Seismo-series, 27. Sætten, J., Bugge, T., Fanavoll, S., Goll, R.M., Mørk, A., Mørk, M.B.E., Smelror, M. & Verdenius, J.G. 1994. Cenozoic development and erosion of the Barents Sea: Core evidence from southwest of Bjørnøya. Marine Geology, 118, 257-281. Sættem, J., 1988. Varmestrømsmålinger i Barentshavet. 18. Nordiske Geologiske Vintermøde, Geological Survey of Denmark (extended abstract), 406-408. Tessensohn, F. (Ed.) 2001. Intra-Continental Fold Belts. Case 1: West Spitsbergen. Geologisches Jahrbuch, Reihe B, 91, 773 p. Timofeeva, T.N., 1982. Middle and Late Devonian volcanic activity in the South Novaya Zemlya. In V.I.

Bondarev (ed.), Geology of the Novaya Zemlya South Island. PGO “Sevmorgeologia”, Leningrad, 68-77. (In Russian). Torsvik, T.H. & Andersen, T.B., 2002. The Taimyr fold belt, Arctic Siberia: timing of prefold remagnetisation and regional tectonics. Tectonophysics, 352, 335-348. Torsvik, T.H. Carlos. D., Mosar, M., Cocks, L.R.M. & Malme, T. 2002. Global reconstructions and North Atlantic palaeogeography 440 Ma to Recent. In Eide, E.A. (coord.), BATLAS — Mid Norway plate reconstruction atlas with global and Atlantic perspectives. Geological Survey of Norway. p 18-39. Tozer, E.T. & Parker, J.R. 1968. Notes on the Triassic biostratigraphy of Svalbard. Geological Magazine, 105, 526-542. Tugarova, M., Pchelina, T., Ustinov, N. & Viskunova, K. 2008. Lithological and geochemical characteristics of Triassic sediments from the South Barents depression (Arkticheskaya-1 well). Polar Research, 27, 495501. Ulmishek, G., 1985. Geology and Petroleum resources of the Barents-Northern Kara shelf in the light of new geological data. Argonne National Laboratory Report ESS-148, 89 p. Verba, M.L., 1985. The Barents-North Kara megatrough and its bearing to the evolution of Western Arctic. In: M.L. Verba Ed., Geological structure of the Barents-Kara Shelf, Leningrad, 11-29. (In Russian). Verba, M.L. & Sakoulina, T.S. 2001. The Reconstruction of the Early Paleozoic Structure of the Barents Sea Sedimentary Basin Inferred from Geophysical Surveys along profil I-AR. Polarforschung, 69, 85-94. Verba M. L., Juravlev V.A. & Bulgak N. N. 1987. Free-air gravity map of the Barents-Kara shelf. Scale 1:2500000 (unpublished). Verba, M.L., Ivanova, N.M., Katsev, V.A., Roslov, Yu. V., Sakoulina, T.S. & Telegin, A.N. 1999. The results of seismic investigations on the regional profiles AR1 and AR-2 in the Barents and Kara seas. Exploration and Protections of Resources. Nedra, Moscow, 3-7 (In Russian). Vigran, J.O. 1986. The Upper Devonian-Carboniferous succession of Bjørnøya – a review of plant macrofossils, palynology and ages. IKU Report 23.1252.01/01/86, 75 p. Vigran, J.O., Mangerud, G., Mørk, A., Bugge, T. & Weitschat, W. 1998. Biostratigraphy and sequence stratigraphy of the Lower and Middle Triassic deposits of the Svalis Dome, Central Barents Sea, Norway. Palynology, 22, 89-141. Vigran, J.O., Mørk, A., Forsberg, A.W., Weiss, H.M. & Weitschat, W. 2008. Tasmanites algae – contributors to the Middle Triassic hydrocarbon source rocks of Svalbard and the Barents Shelf. Polar Research 27, 360-371. Weitschat, W. & Lemann, U. 1983. Stratigraphy and ammonoids from the Middle Triassic Botneheia Formation (Daonella shales) of Spitsbergen. Mitteilungen. Geol. Paleontol. Inst. Univ. of Hamburg, 54, 27-54. Wierzbowski, A. 1989. Ammonites and stratigraphy of the Kimmeridgian at Wimanfjellet, Sassenfjorden, Spitsbergen. Acta Palaeont. Polon., 34: 355-378.

Literature - References

133

Wierzbowski, A. & Smelror, M. 1993. Ammonite succession in the Kimmeridgian of southwestern Barents Sea, and the Amoeboceras zonation of the Boreal Kimmeridgian. Acta Geol. Polon., 43, 229-249.

Worsley, D., Aga, O.J., Dalland, A., Elverhøi, A. & Thon, A. 1986. The Geological History of Svalbard – Evolution of an Arctic Archipelago. Statoil, Stavanger, 212 p.

Worsley, D. 2008. The post-Caledonian geological development of Svalbard and the Barents Sea. Polar Research, 27, 298-317.

Worsley, D., Agdestein, T., Gjelberg, J.G., Kirkemo, K., Mørk, A., Nilsson, I., Olaussen, S., Steel, R.J. & Stemmerik, L. 2001. The geological evolution of Bjørnøya, Arctic Norway: Implications for the Barents Shelf. Norsk Geologisk Tidsskrift, 81, 195-234.

Worsley, D. & Edwards, M.B. 1976. The Upper Palaeozoic succession of Bjørnøya. Norsk Polarinstitutt Årbok 1974, 17-34.

134

Literature - References

Zakharov, V.A., Surlyk, F. & Dalland, A. 1981. Upper Jurassic - Lower Cretaceous Buchia from Andøy, northern Norway. Norsk Geologisk Tidsskrift, 61, 261.

Ziegler, P.A., 1988. Evolution of the Arctic-North Atlantic and the Western Tethys. AAPG Memoir 43. Zielinski, G.R., Gunleiksrud, T., Sættem, J., Zuidberg, H.M., and Geise, J. M., 1986. Deep heat flow measurements in Quaternary sediments on the Norwegian continental shelf. Offshore Techology Conference Houston, TX 1986, 277-282. Århus, N. 1991. Dinoflagellate cyst stratigraphy of some Aptian and Albian sections from North Greenland, southern Spitsbergen and the Barents Sea. Cretaceous Research, 12, 209-225.

Amfiet, Bjørnøya. Photo: Odd Harald Hansen

Authors:

Valeri A. Basov Jรถrg Ebbing Laurent Gernigon Marianna V. Korchinskaya Tatyana Koren Natalia V. Kosteva Galina V. Kotljar Geir Birger Larssen Tamara Litvinova Oleg. B. Negrov Odleiv Olesen Christophe Pascal Tatyana M. Pchelina Oleg V. Petrov Yugene O. Petrov Hans-Ivar Sjulstad Morten Smelror Nikolay V. Sobolev Victor Vasiliev Stephanie C. Werner

ISBN 978-82-7385-137-6