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GEOLOGY APPLIED TO ENGINEERING Second Edition

Terry R. West Abdul Shakoor

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Data Pertaining

to

Planet Earth

Equatorial Radius

6378 km

3963 mi

Polar Radius

6356 km

3949 mi

Volume

1.083 × 1012 km3

259.4 × 109 mi3

Surface Area

5.10 × 108 km2

1.97 × 108 mi2

Mass

5.9722 × 1024 kg

6.58 × 1021 tons

Density

5.513 g/cm3

344 lb/ft3

Average Land Elevation

622 m

2040 ft

Average Ocean Depth

3.8 km

2.36 mi

Acceleration of Gravity at Equator

9.807 m/sec2

32.088 ft/sec2

Mean Distance to Sun

1.496 × 108 km

92.6 × 106 mi = 1 AU

Escape Velocity

11.2 km/sec

25,054 mi/hr

Mass Ratios

Mass of Sun = 3.329 ¥ 105 Mass of Earth Mass of Earth = 81.303 Mass of Moon

Volume of Sphere

4/3 πr3

Surface Area of Sphere

4 πr2

Geologic Time Scale Era

Period

Quaternary Cenozoic

Neogene Paleogene

Mesozoic

Paleozoic

Precambrian

Epoch

Duration (Years)

Holocene Pleistocene Pliocene Miocene

11,800 2.58 million 2.7 million 17.7 million

Oligocene Eocene Paleocene

10.9 million 21.9 million 9.7 million

Cretaceous Jurassic Triassic Permian Pennsylvanian Mississippian Devonian Silurian Ordovician Cambrian Proterozoic Eon Archean Eon

Origin of Earth

80 million 54.3 million 51.4 million 48 million 19.1 million 41.1 million 56.8 million 27.7 million 44.6 million 53.7 million 1958 million 2642 million

Age of Boundary (Years Before Present)

2.59 million 23 million

65.5 million

251 million

542 million

4.6 billion

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Common Conversion Factors, British Engineering Units British

×

to

SI Units

SI

inch

25.4

millimeters

foot

0.3048

meters

yard

0.9144

meters

mile

1.609

kilometers

square inch

6.452

square centimeters

square foot

0.0929

square meters

acre

0.405

hectares

square mile

2.590

square kilometers

ounce, mass

28.35

grams

pound, mass

0.4536

kilograms

short ton, mass

0.9072

metric tons

pound, force

4.448

newtons

short ton, force

8.896

kilonewtons

psf

47.88

pascals

psi

6.895

kilopascals

psi

6.895 × 10–3

megapascals

short ton/square foot

95.76

kilopascals

ton/square foot

1.024

kilograms/square meters

atmosphere (STP)

101.3

kilopascals

bar

100

kilopascals

fluid ounce

30

milliliters

quart

0.95

liters

gallon

3.8

liters

pound, force per cubic foot

16.018

kilograms/cubic meters

mile per hour

1.609

kilometers/hour

feet per year

0.966 × 10–6

BTU kilowatt-hour

centimeters/second

252

calories

860,421

calories

SI to British conversion factors are the reciprocals of the conversion values shown above.

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GEOLOGY APPLIED TO ENGINEERING Second Edition

Terry R. West Purdue University

Abdul Shakoor Kent State University

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In all things of nature there is something of the marvelous.

Aristotle 388–322 bc

For information about this book, contact: Waveland Press, Inc. 4180 IL Route 83, Suite 101 Long Grove, IL 60047-9580 (847)634-0081 info@waveland.com www.waveland.com

Photo Credits. Chapter 1: Reto Stockli, Alan Nelson, and Fritz Hasler, NASA, Earth Observatory.

Chapter 2: Marcel Clemens, Shutterstock. Chapter 3: onime, Shutterstock. Chapter 4: V. J. Matthew, Shutterstock. Chapter 5: corlaffra, Shutterstock. Chapter 6: Les Palenik, Shutterstock. Chapter 7: Skinfaxi, Shutterstock. Chapter 8: farbled, Shutterstock. Chapter 9: Mehmet Cetin, Shutterstock. Chapter 10: Corrado Baratta, Shutterstock. Chapter 11: Matauw, Shutterstock. Chapter 12: Claudio Del Luongo, Shutterstock.

Chapter 13: Blur Life 1975, Shutterstock. Chapter 14: tony740607, Shutterstock. Chapter 15: Have a Nice Day Photo, Shutterstock. Chapter 16: Matthew J. Thomas, Shutterstock. Chapter 17: Julien Hautcoeur, Shutterstock.

Chapter 18: Andrey VP, Shutterstock. Chapter 19: Labrador Photo Video, Shutterstock. Chapter 20: elvistudio, Shutterstock. Chapter 21: Andrew Zarivny, Shutterstock.

Copyright © 2018 Terry R. West and Abdul Shakoor 10-digit ISBN 1-4786-3500-2 13-digit ISBN 978-1-4786-3500-0 All rights reserved. No part of this book may be reproduced, stored in a retrieval ssytem, or transmitted in any form or by any means without permission in writing from the publisher.

Printed in the United States of America 7 6 5 4 3 2 1

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Contents Preface · · · · · · · · · · · · · · · · · · · xv Acknowledgments· · · · · · · · · · · · · · xvi

1 Origin and Development of the Earth . . . . . . . . . . . . . . . . .

Modern Theory of the Origin of the Universe. . . . . . . . . . . . .

1

2

The Evolving Universe Theory 2 Stages of Star Development 3

Origin of the Solar System . . . . . . . . . . . . . . . . . . . . 3 Nebular Hypotheses 4

The Milky Way . . . . . . . . . .

The Likelihood of Life on Other Planets . .

The Fate of Life on Earth . . . . . . .

Configuration of the Earth’s Surface. . .

. . . . . . . .

Early Developments 8 Melting of the Earth 9 Formation of the Oceans and Atmosphere 9

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . .

Architecture of the Earth’s Surface Today . . . . . . . . . . . . . .

Seafloor Spreading 10 Plate Tectonics 11

5 6 8 8

10

Exercises on the Origin and Development of the Earth 13 References 14

2 Minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Mineral Definition . . .

Mineral Formation. . .

Occurrence of Minerals .

Mineral Identification . .

Rock-Forming Minerals. .

. . . . . . . . . . . . . . . . . . . .

Silicates 24 Oxide Minerals 26 Sulfide Minerals 26 Carbonate Minerals 26 Sulfate Minerals 26 Clay Minerals 27 Zeolites 30

. . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . .

17 18 18 19 24

Engineering Considerations of Minerals. . . . . . . . . . . . . . . 30 Exercises on Minerals 30 References 31 iii

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iv Contents

3 Igneous Rocks . . . . . . . . . . . . . . . . . . . . . . . . . 33 Definitions of Rock. . . . . . . . . . . . . . . . . . . . . .

Geologic Definition 33 Engineering Definition 33

33

Definition and Occurrence of Igneous Rocks . . . . . . . . . . . . . 34 Formation of Igneous Rocks . . . . . . . . . . . . . . . . . . . 34 Types of Volcanoes. . . . . . . . . . . . . . . . . . . . . . 35 Shield Volcanoes 36 Cinder Cones 36 Composite Volcanoes 36 Morphology of Volcanoes 37

Fissure Eruptions. . . . . . . . . . . . . . . . . . . . . . .

Volcanic Deposits. . . . . . . . . . . . . . . . . . . . . . .

Pyroclastic Deposits. . . . . . . . . . . . . . . . . . . . . .

Fumaroles, Geysers, and Hot Springs. . . . . . . . . . . . . . . .

Intrusive Rock Bodies . . . . . . . . . . . . . . . . . . . . .

Igneous Rock Textures . . . . . . . . . . . . . . . . . . . . .

Mineralogy of Igneous Rocks. . . . . . . . . . . . . . . . . . .

Classification of Igneous Rocks. . . . . . . . . . . . . . . . . .

Igneous Rock Descriptions . . . . . . . . . . . . . . . . . . .

Engineering Considerations of Igneous Rocks. . . . . . . . . . . . .

Exercises on Igneous Rocks 48 References 49

37 39 40 40 41 43 45 45 46 47

4 Rock Weathering and Soils. . . . . . . . . . . . . . . . . . . . . 51 Factors Controlling Weathering. . . . . . . . . . . . . . . . . . 51 Role of Water 51 Topographic Expression 52

Processes of Mechanical Weathering. . . . . . . . . . . . . . . .

Differential Expansion and Contraction 52 Frost Wedging 52 Sheeting and Exfoliation 53 Spheroidal Weathering 54 Differential Weathering 54 Other Mechanical Weathering Processes 54

52

Processes of Chemical Weathering. . . . . . . . . . . . . . . . . 56 Surface Area Effects 56 Solution, Oxidation, Hydrolysis, and Effects of Plants 56 Resistance to Weathering 57 Effects of Climate 57

Classification of Weathering Grade. . . . . . . . . . . . . . . . . 58 Soil Profiles. . . . . . . . . . . . . . . . . . . . . . . . . 59 Definitions of Soil 59

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Contents v Factors Controlling Soil Profile Development. . . . . . . . . . . . .

Parent Material 61 Climate 62 Time 63 Topography and Vegetation 63

60

Classification of Soil Particle Size and Texture. . . . . . . . . . . . . 64 Clay Size versus Clay Mineral 64 Textural Classifications 64

Agricultural Soils Maps. . . . . . . . . . . . . . . . . . . . . 64 Engineering Considerations of Rock Weathering and Soils. . . . . . . . . 66 Exercises on Rock Weathering and Soils 68 References 70

5 Sedimentary Rocks . . . . . . . . . . . . . . . . . . . . . . .

Definition and Occurrence of Sedimentary Rocks.

Sediments versus Sedimentary Rocks. . . . .

Lithification. . . . . . . . . . . . . .

Formation of Sedimentary Rocks. . . . . . .

Sedimentary Rock Classification. . . . . . .

Clastic Sedimentary Rocks 73 Coarsely Crystalline Sedimentary Rocks 75 Fine-Grained or Cryptocrystalline Rocks 76 Whole Fossil Rocks 77

. . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . .

71

. . . 71 . . . 72 . . . 72 . . 72 . . . 73

Sedimentary Rock Identification. . . . . . . . . . . . . . . . . . 77 Distinguishing Features of Sedimentary Rocks. . . . . . . . . . . . . 78 Bedding 78 Bedding Plane Features 79 Secondary Structures 83

Environments of Deposition . . . . . . . . . . . . . . . . . . . 85 Continental Environment 85 Mixed Environments 86 Marine Environment 86 Additional Details of Carbonate Deposition 88

Engineering Considerations of Sedimentary Rocks . . . . . . . . . . .

Exercises on Sedimentary Rocks 90 References 91

88

6 Metamorphic Rocks . . . . . . . . . . . . . . . . . . . . . . . 93 Definition and Occurrence of Metamorphic Rocks . . . . . . . . . . .

Types of Metamorphism . . . . . . . . . . . . . . . . . . . .

Geologic Rock Cycle . . . . . . . . . . . . . . . . . . . . .

Textures of Metamorphic Rocks. . . . . . . . . . . . . . . . . .

Types of Metamorphic Rocks. . . . . . . . . . . . . . . . . . .

Metamorphic Grade. . . . . . . . . . . . . . . . . . . . . .

Metamorphic Rock Identification. . . . . . . . . . . . . . . . .

93 93 94 95 95 97 98

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vi Contents Rock Identification for All Three Varieties . . . . . . . . . . . . . .

Hardness 98 Diagnostic Minerals 98 Directional Features 99 Other Features 99

98

Engineering Considerations of Metamorphic Rocks . . . . . . . . . . . 99 Exercises on Metamorphic Rocks 101 References 101

7 Elements of Soil Mechanics . . . . . . . . . . . . . . . . . . . . 103 Index Properties . . . . . . . . . . . . . . . . . . . . . .

Soil Texture 104 Grain Size Distribution 104 Particle Shape and Roundness 106 Phase Relationships 106 Atterberg Limits 114

103

Soil Classification. . . . . . . . . . . . . . . . . . . . . . 116 Unified Soil Classification System 116 AASHTO Classification System 116

Soil Structure . . . . . . . . . . . . . . . . . . . . . . .

Structure of Cohesionless Soils 117 Structure of Cohesive Soils 119

117

Compaction . . . . . . . . . . . . . . . . . . . . . . . . 122 Engineering Significance of Compaction 123 Factors Affecting Compaction 123 Laboratory Tests 123 Properties of Compacted Cohesive Soils 125 Compaction and Excavation Equipment 126 Field Compaction Control 128

Effective Stress . . . . . . . . . . . . . . . . . . . . . . . 130 Definition 130 Basic Calculations 130 Effects of Water Flow 132 Critical Hydraulic Gradient 133

Shear Strength of Soils. . . . . . . . . . . . . . . . . . . .

Stress at a Point 134 Principal Stresses 134 Mohr Circle 135 Mohr–Coulomb Failure Criterion 138

134

Stress Distribution . . . . . . . . . . . . . . . . . . . . . . 144 Two-to-One Method 145 Boussinesq Formula 145 Westergaard Formula 146 Newmark Influence Chart 147

Consolidation. . . . . . . . . . . . . . . . . . . . . . .

148

Engineering Considerations of Soil Mechanics. . . . . . . . . . . .

Exercises on Elements of Soil Mechanics 153 References 158

152

Laboratory Testing 149

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Contents vii

8 Engineering Properties of Rocks. . . . . . . . . . . . . . . . . .

159

Properties of Intact Rock. . . . . . . . . . . . . . . . . . . . 159 Specific Gravity, Absorption, Porosity, Degree of Saturation, and Unit Weight 159 Rock Strength 160 Elastic Properties of Rocks 166 Rock Durability 169

Engineering Classification of Intact Rock. . . . . . . . . . . . . . 170 Rock Mass Properties . . . . . . . . . . . . . . . . . . . . . 172 Engineering Classification of Rock Mass. . . . . . . . . . . . . . 174 Percent Core Recovery 174 Rock Quality Designation 174 Fracture Index 174 Velocity Index 174 Rock Mass Classification Systems 174

Rock Strength and Petrography . . . . . . . . . . . . . . . . . 176 Engineering Considerations of Rock Properties . . . . . . . . . . . . 177 Exercises on Engineering Properties of Rocks 178 References 181

9 Evaluating Construction Materials . . . . . . . . . . . . . . . . .

183

Introduction . . . . . . . . . . . . . . . . . . . . . . . . 183 Testing Construction Materials . . . . . . . . . . . . . . . . . 184 Strength Test 184 Durability Tests 185 Other Tests for Evaluating Aggregates 186

Portland Cement Concrete. . . . . . . . . . . . . . . . . . . 186 Concrete Composition 186 Petrographic Examination of Concrete 188

Engineering Considerations of Construction Materials. . . . . . . . .

Exercises on Evaluating Construction Materials 190 References 190

189

10 Stratigraphy and Geologic Time. . . . . . . . . . . . . . . . . .

Stratigraphy. . . . . . . . . . . . . . . . . . . . . . . . 194 Basic Geologic Principles for Relative Age Dating. . . . . . . . . . . 194 Principle of Original Horizontality and Continuity 194 Principle of Superposition 194 Principle of Faunal Assemblage 195 Principle of Crosscutting Relationships 195 Principle of Baked Contacts 195 Principle of Inclusions 195 Principle of Uniformitarianism 195

Unconformities. . . . . . . . . . . . . . . . . . . . . . . 195 Types of Unconformities 195 Nonconformity versus Intrusive Contact 196

Correlation. . . . . . . . . . . . . . . . . . . . . . . .

Complications in Correlation 198

197

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193

viii Contents Dating the Earth. . . . . . . . . . . . . . . . . . . . . . . 198 Early Speculation and Scientific Estimates about the Earth’s Age 199 Seventeenth-Century Biblical Scholars 199 Eighteenth- and Nineteenth-Century Scientific Studies 199 Geologic Time Scale 201

Absolute or Radiometric Dating. . . . . . . . . . . . . . . . .

Emission of Particles 201 Decay of U238 201 Decay Constants 205 Calculations for Decay Constant and Half-Life 206 Limitations of Isotope Dating 206 Age Dating Based on Uranium, Thorium, and Lead 207 Age Dating Using Rubidium and Strontium 207 Age Dating from Potassium and Argon 208 Radiocarbon Dating 208 Fission Track Dating 209 Absolute Age of the Earth 210

The Awesome Span of Geologic Time . . . . . . . . . . . . .

Human Time versus Geologic Time . . . . . . . . . . . . . .

Geologic Maps . . . . . . . . . . . . . . . . . . . . .

Engineering Considerations of Statigraphy and Geologic Time. . . . .

Exercises on Stratigraphy and Geologic Time 214 References 217

201

. . 210 . . 210 . . 211 . . 212

11 Structural Geology. . . . . . . . . . . . . . . . . . . . . . . 219 Rock Deformation . . . . . . . . . . . . . . . . . . . . . . 219 Folds in Rock. . . . . . . . . . . . . . . . . . . . . . . . 220 Fold Terminology 220 Strike and Dip 220 Anticlines and Synclines 223 Domes and Basins 224 Structural Geology Symbols 225

Types of Rock Fractures . . . . . . . . . . . . . . . . . . . . 226 Joints 226 Shear Zones 226 Faults 227

Folds and Faults Combined . . . . . . . . . . . . . . . . . . . 230 Direction of Stress and Fault Orientation. . . . . . . . . . . . . . 231 Engineering Considerations of Structural Geology . . . . . . . . . . . 233 Exercises on Structural Geology 234 References 235

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Contents ix

12 Running Water and River Systems . . . . . . . . . . . . . . . . . . 241 Hydrologic Cycle and Rainfall Equation . . . . . . . . . . . . . . 241 Factors Influencing Runoff. . . . . . . . . . . . . . . . . . . 242 Types of Runoff . . . . . . . . . . . . . . . . . . . . . . . 243 Laminar Flow 244 Turbulent Flow 244 Jet or Shooting Flow 244 Intermittent and Perennial Streams 244

Stream Flow Terms . . . . . . . . . . . . . . . . . . . . . . 244 Velocity 244 Gradient 245 Discharge 245 Flooding 245 Stream Hydrograph 246 Load 246 Three Views of a Stream 246 The Economy of Stream Flow 247

Work of Streams . . . . . . . . . . . . . . . . . . . . . .

Erosion 250 Transportation 253 Deposition 254

250

Landform Features of Streams. . . . . . . . . . . . . . . . . . 254 Drainage Patterns 254 Drainage Basins and Divides 255 Depositional Forms in Alluvial Valleys 255 Channel Patterns 255 Deltas, Alluvial Fans, and Stream Terraces 256 Erosional Features 257

Engineering Considerations of Running Water and River Systems. . . . . . 259 Problems of Wide Floodplain Areas 259 Problems of Upland Stream Locations 261

Exercises on Running Water and River Systems 262 References 264

13 Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . 265 Origin of Groundwater. . . . . . . . . . . . . . . . . . . .

266

Distribution of Groundwater. . . . . . . . . . . . . . . . . .

267

Connate Water 266 Magmatic Water 266

Subsurface Distribution 267 Vadose Zone 267 Water Table 268 Zone of Phreatic Water 269

Confined and Unconfined Water. . . . . . . . . . . . . . . . . 269 Porosity and Related Properties. . . . . . . . . . . . . . . . . 270 Permeability . . . . . . . . . . . . . . . . . . . . . . . . 271 Darcy’s Law 271 Permeability Units 272 Measuring Permeability 273

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x Contents Springs . . . . . . . . . . . . . . . . . . . . . . . . . . 282 Groundwater Movement. . . . . . . . . . . . . . . . . . . . 284 Production of Groundwater . . . . . . . . . . . . . . . . . . 286 Production from Unconsolidated Materials 287 Production from Bedrock 288

Water Well Terminology . . . . . . . . . . . . . . . . . . . . 288 Legal Details of Groundwater Ownership . . . . . . . . . . . . . . 290 Groundwater Rights Based on Land Ownership 290 Development of Water Rights and Conservation 290 Legal Complications 291

Water Witching . . . . . . . . . . . . . . . . . . . . . . . 292 Groundwater Pollution. . . . . . . . . . . . . . . . . . . . 293 Septic Tank Fields 293 Sanitary Landfills 297 Miscellaneous Groundwater Pollution 298 Saltwater Encroachment 301

Formation of Caves in Carbonate Rocks. . . . . . . . . . . . . . 302 Engineering Considerations of Groundwater . . . . . . . . . . . . . 305 Exercises on Groundwater 306 References 308

14 The Work of Glaciers . . . . . . . . . . . . . . . . . . . . . . 309 Glacial Ice . . . . . . . . . . . . . . . . . . . . . . . . . 309 Types of Glaciers. . . . . . . . . . . . . . . . . . . . . . 310 Results of Glaciation . . . . . . . . . . . . . . . . . . . . . 310 Valley Glaciers 310 Continental Glaciers 315

Glacial History of the United States . . . . . . . . . . . . . . . . 318 Glacial Stages 318 History of the Great Lakes 322

Engineering Considerations of the Work of Glaciers. . . . . . . . . .

Exercises on The Work of Glaciers 324 References 326

322

15 Slope Stability and Ground Subsidence . . . . . . . . . . . . . . . . 327 Classification of Mass Movement. . . . . . . . . . . . . . . . . 327 Types of Slope Movement. . . . . . . . . . . . . . . . . . . 328 Falls 331 Topples 331 Slides 332 Lateral Spreads 344 Flows 346 Creep and Other Flow Type Movements 347 Complex Slope Movements 349

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Contents xi Causes of Slope Movements. . . . . . . . . . . . . . . . . .

350

Prevention and Correction of Slope Movements . . . . . . . . . . .

Ground Subsidence. . . . . . . . . . . . . . . . . . . . .

354 354

Excessive Precipitation 350 Earthquakes 351 Human Activities 352

Compaction and Consolidation 357 Plastic Outflow 360 Underground Opening Collapse 360

Engineering Considerations of Slope Stability and Ground Subsidence . . . . 364 Exercises on Slope Stability and Ground Subsidence 365 References 367

16 Coastal Processes. . . . . . . . . . . . . . . . . . . . . . .

Wave Motion. . . . . . . . . . . . . . . . . . . . . . . . 369 Oscillatory Waves 370 Waves in Shallow Water 371 Wave Paths and Erosive Forces 371

Tides. . . . . . . . . . . . . . . . . . . . . . . . . .

Location and Frequency of Tides 373 Causes of Tidal Fluctuations 375 Spring Tides and Neap Tides 375 Details on Tidal Extremes 375 Locations with Maximum Tidal Effects 375

373

Effects of Severe Storms . . . . . . . . . . . . . . . . . . . . 376 Erosion in Coastal Areas. . . . . . . . . . . . . . . . . . . . 377 Factors in Wave Erosion 377 Landform Features in Massive Rock 377

Deposition in Coastal Areas . . . . . . . . . . . . . . . . . .

378

Estuaries. . . . . . . . . . . . . . . . . . . . . . . . .

381

Beaches 378 Sea Terraces 379 Spits and Sand Bars 379 Barrier Islands 379 Dune Ridges 379

Uses of Estuaries 381 Pollution of Estuaries 381

Classification of Coastlines . . . . . . . . . . . . . . . . . . . 382 Sensitivity of Shoreline Features to Human Activities . . . . . . . . . . 383 Engineering Considerations: Shoreline Protection Structures. . . . . . . 383 Exercises on Coastal Processes 387 References 389

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369

xii Contents

17 Arid Environments and Wind. . . . . . . . . . . . . . . . . . .

391

Arid Climates . . . . . . . . . . . . . . . . . . . . . . . 391 Geologic Processes in Arid Regions. . . . . . . . . . . . . . . . 392 Wind . . . . . . . . . . . . . . . . . . . . . . . . . . 396 Action of the Wind 396 Wind Erosion 397 Wind Deposits 398 Loess Deposits 399

Engineering Considerations of Arid Environments and Wind. . . . . . .

Exercises on Arid Environments and Wind 402 References 403

402

18 Earthquakes and Geophysics . . . . . . . . . . . . . . . . . . .

405

Earthquake Studies. . . . . . . . . . . . . . . . . . . . . . 405 Types of Waves 405 Earthquake Scales 408 Earthquake Damage 410 Geologic Investigations of Earthquake Prone Areas 414 Locating Earthquakes Using Seismology 416 Causes of Earthquakes 417 Earthquake Prediction 417 Earthquake Distribution 418 Earthquakes of the United States 419 Human-Induced Earthquakes 425

The Earth’s Interior . . . . . . . . . . . . . . . . . . . . .

Crust 426 Mantle 427 Core 427

426

Engineering Geophysics. . . . . . . . . . . . . . . . . . . . 428 Seismic Methods 428 Gravity and Magnetic Methods 428 Electrical Methods 429 Ground Penetrating Radar 429 Well Logging Methods 430 Refraction Seismic Method 432 Earth Resistivity Method 437 Selection of Geophysical Exploration Methods 443

Engineering Considerations of Earthquakes and Geophysics . . . . . . .

Exercises on Earthquakes and Geophysics 446 References 449

446

19 Subsurface Investigations. . . . . . . . . . . . . . . . . . . . . 451 Subsurface Model . . . . . . . . . . . . . . . . . . . . . . 451 Reconnaissance. . . . . . . . . . . . . . . . . . . . . . . 452 Office Reconnaissance 452 Field Reconnaissance 455 Procedure for Reconnaissance 458

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Contents xiii Subsurface Exploration: Sounding, Drilling, and Sampling. . . . . . . .

Soundings 458 Drilling Methods 458 Sampling Methods 460

458

Miscellaneous Considerations . . . . . . . . . . . . . . . . . . 473 Site Selection . . . . . . . . . . . . . . . . . . . . . . . 474 Engineering Considerations of Subsurface Investigations. . . . . . . . . 474 Exercises on Subsurface Investigations 475 References 476

20 Physiographic Provinces . . . . . . . . . . . . . . . . . . . . . 477 Physiographic Provinces. . . . . . . . . . . . . . . . . . . . 477 Factors Affecting Physiography . . . . . . . . . . . . . . . . . 480 Rock Type and Geologic Structure 480 Geologic Processes 481 Stage 481

Subdividing Physiographic Provinces . . . . . . . . . . . . . . .

Sections 485 Divisions on a State Basis 485

485

Engineering Considerations of Physiographic Provinces . . . . . . . . . 489 Exercises on Physiographic Provinces 491 References 494

21 Engineering Geology: Highways, Dams, Tunnels, and Rock Blasting . . . . . . . . . . . . . 495 Engineering Geology . . . . . . . . . . . . . . . . . . . . . 495 Examples of Construction Projects Related to Engineering Geology 496

Engineering Geology of Highways . . . . . . . . . . . . . . . .

Highway Location 497 Subsurface Investigations 497 Balancing Cut and Fill Volumes 498 Overbreak and Presplitting 499 Cut-Slope Angle 499 Groundwater Problems 499 Areas Prone to Slope Movements 500 Legal Aspects 500 Construction Materials: Location and Inventory 500 Human Activity Considerations 500

497

Engineering Geology of Dams. . . . . . . . . . . . . . . . . . 500 Classification of Dams 501 Materials for Dam Construction 506 Exploration for Dams 506 Grouting 507 Malpasset Dam Failure—A Case History Illustrating the Role of Geology 508

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xiv Contents Engineering Geology of Tunnels. . . . . . . . . . . . . . . . .

Site Investigations 509 Estimating Overburden Pressure 509 Standup Time 511 Geologic Hazards during Tunneling 511 Tunneling Procedures 512 Tunnel Supports 513

508

Rock Blasting. . . . . . . . . . . . . . . . . . . . . . . . 514 Blast-Damage Criterion 514 Blast-Induced Ground Vibrations 515 Effects of Air Blasts 516

Environmental Geology . . . . . . . . . . . . . . . . . . . . 516 Large-Scale Interpretive Maps 517

Exercises on Engineering Geology: Highways, Dams, Tunnels, and Rock Blasting 519 References 529

Appendix A: Identification of Minerals and Rocks . . . . . . . . . . . . . . 531 Minerals. . . . . . . . . . . . . . . . . . . . . . . . .

Rocks. . . . . . . . . . . . . . . . . . . . . . . . . .

Igneous Rocks 538 Sedimentary Rocks 541 Metamorphic Rocks 542 General Considerations 542

531 538

Appendix B: Topographic Maps . . . . . . . . . . . . . . . . . . . . 544 Elements of Topographic Maps . . . . . . . . . . . . . . . . .

Latitude and Longitude 545 Map Scale 547 Converting Scales 548 Topography 549 Location by the Township and Range System 552 Gradients or Slopes 553 Compass Directions 553

545

Geologic Maps of Horizontal Rocks . . . . . . . . . . . . . . . . 553 Exercises on Topographic Maps 557 Index · · · · · · · · · · · · · · · · · · · 561

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Preface

Geology Applied to Engineering, Second Edition, represents a significant and insightful update of the first edition. Abdul Shakoor, Emeritus Professor, Kent State University, Ohio, has joined Terry West, Professor, Purdue University, Indiana, in the revision of the first edition. Together, they: • Effectively and strategically reorganized the arrangement of chapters so that they are cohesive and build on material that is germane to related subjects.

• Added a new chapter that is solely dedicated to the evaluation of construction materials (Chapter 9).

• Expanded the coverage and scope of important topics such as the engineering properties of rocks (Chapter 8), slope stability and ground subsidence (Chapter 15), and significant fields in engineering geology, such as highways, dams, tunnels, and rock blasting (Chapter 21).

The authors have also taken into consideration the use of the text in the classroom. To benefit instructors and students alike, they have expanded the following features of the text to enhance comprehension of the material.

• Throughout the text SI units and their conversion to British engineering units are provided.

Solutions to the Example Problems are calculated in both units to facilitate the growing need for the implementation of SI units within the engineering geology and geotechnical fields.

• Equations are numbered for easy reference.

• Numerous high-quality images are included to help better illustrate the physical processes at work below and at the Earth’s surface. New examples of minerals, rocks, landforms, engineering structures, and equipment have been supplied.

• In conjunction with the text, the authors have added a new section at the end of each chapter called Engineering Considerations. Insightful and relevant, this material outlines real-world practices, concerns, and issues for today’s engineering geologists and geotechnical engineers.

• Throughout the Second Edition current citations and references to pertinent testing procedures are presented to link the material to a professional setting.

Geology Applied to Engineering represents a thorough and up-to-date textbook for courses in Applied Physical Geology, Geology for Engineers, and Engineering Geology at both the undergraduate and graduate levels. It contains appropriate information for geologists and engineers who are involved in designing and constructing engineering structures, as all structures are located either on the Earth or in the Earth, or composed of earth materials. This textbook also provides the fundamentals of subject material included in the Examination for Professional Licensure of Geologists, a growing need for geologists who work in the public sector. xv

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xvi  Acknowledgments

Acknowledgments Our sincere thanks go to the students, colleagues, teachers, staff, family, and friends who contributed valuable ideas on teaching basic and applied geology at the university level. During the many years that the coauthors have been privileged to teach as university professors, we have taught the basic concepts of geology applied to engineering to hundreds of undergraduate students and dozens of graduate students. This book is a visible product of the lasting feeling of accomplishment that comes with extended university careers.

We wish to dedicate this publication to our wives, Shirley Mueller West and Roohi Shakoor, for their everlasting support and encouragement. Thank you, both.

Terry R. West Abdul Shakoor 2018

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Origin and Development of the Earth

1 Chapter Outline

Modern Theory of the Origin of the Universe Origin of the Solar System The Milky Way The Likelihood of Life on Other Planets

The Fate of Life on Earth Configuration of the Earth’s Surface Architecture of the Earth’s Surface Today

patches of light that a telescope is unable to resolve sharply into a single point. These are nebulae, other galaxies that exist beyond the Milky Way, which is the galaxy in which Earth orbits. Galaxies, the building blocks of the universe, vary in size and form, but many are spiral-shaped with curved arms trailing from their centers. When viewed along their spiral diameter, they appear as a disk that bulges outward at the center. The nearest galaxy to the Milky Way is Andromeda, located 2.2 million light-years away.

Astronomers estimate that up to 200 billion galaxies exist in the universe. Recent studies from the Hubble telescope suggest the number could be significantly higher than this.

The Milky Way is home to all the stars that we can see clearly without a telescope; they number from 100 to 400 billion stars. In the Milky Way, stars are more or less clustered together to form the constellations, which were named centuries ago with reference to animals, mythical gods, famous people, or common objects. About 90 constellations have been

This chapter discusses the Earth’s origin and development, beginning with the universe and then focusing on the details of the Earth itself. Information about the solar system and the universe, with some ideas on their origin, is included in the discussion.

The universe (cosmos) extends in all directions as far as we can detect matter. It is approximately 13.7 billion years old and has an estimated diameter of at least 10 billion light-years (8.8 × 1023 km or 5.5 × 1023 mi) (Liddle, 2003; de Bernardis et al., 2008; Lawrence, 2015). For reference, 1 light-year is the distance light travels in a year and is equal to 9.3 × 1012 km (5.8 × 1012 mi). The speed of light is 2.998 × 105 km/sec (1.863 × 105 mi/sec). From this we conclude that the universe is immense beyond human comprehension, with unit distances measured in light-years and with total dimensions measuring in the billions of light-years.

The points of light we see in the sky at night are mostly stars. Only a few are planets moving visibly across the sky and, occasionally, there are hazy 1

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2 Chapter One

Modern Theory of the Origin of the Universe Light that began its journey hundreds, thousands, millions, and even billions of years ago is only now being received on Earth from different locations in the universe. Because the extent of the universe is so vast, the past is revealed to us on a delayed basis; thus, we can compare the past directly with the present. One fact learned by studying these delayed messages is that energy and matter functioned in the distant past much as they do today. This reinforces the hypothesis proposed by geologists that uniform physical laws have driven the geologic processes throughout the Earth’s history.

We know enough about cosmology (the structure of the universe) to construct theories about the origin of the universe. As with most theory development, one must start with a list of known facts and attempt to build a theory consistent with those basic data. Such facts are as follows: • The universe is vast and extends as far as humans can measure.

• Mass is concentrated into collections of stars known as galaxies.

• Stars undergo stages of development from red giants to white dwarfs.

• The universe is expanding, with stars at the periphery moving away the fastest.

The last item in the above list deserves further consideration. Expansion of the universe is indicated by the Doppler effect. This phenomenon shows that the frequency of light or sound lowers as an object accelerates away from the observer. For example, the pitch (frequency) of an automobile horn decreases as the car accelerates away from a point of reference.

Because light emitted from the farthest stars shifts or displaces toward the red end of the visible spectrum, its frequency reduces (c = λυ, where c is the speed of light [a constant]; λ is the wavelength [in units of length]; and υ is the frequency of the waves [1/time]).

Therefore, the stars must be accelerating away from the observer.

The Evolving Universe Theory If matter is accelerating away from a central location and the rate of acceleration and the distance can be estimated, one can estimate how long ago matter expanded from the common source. This forms the basis of the Evolving Universe or Big Bang theory.

Although several theories about the origin of the universe have been proposed in the past, the Evolving Universe theory is currently the widely accepted theory.

According to this prevailing theory, the universe sprang into existence as an extremely dense and intensely hot singularity. It inflated (Big Bang) and expanded, hurling matter and radiant energy into space and bringing about the creation of the present chemical elements (Chaisson and McMillan, 2016).

This event happened about 13.7 billion years ago.

As expansion occurs, the density of matter becomes less (i.e., volume increases; mass remains constant; mass/volume, or density, decreases).

The initial central mass consisted of subatomic particles not yet organized into elements. The elements formed when protons, neutrons, and electrons united during the expansion process. The elements were built in turn from these building blocks, with neutrons and protons grouping together by fusion to yield elements of greater and greater atomic number.

Hence, the abundance (frequency) of the elements in the universe decreases with increasing atomic number. This relationship is illustrated in Figure 1.1.

Logarithm of relative abundance

named, based on the forms they seemed to resemble.

Today, constellations are used as navigational aids and as a convenience to orient and describe locations in the sky.

8 6 4 2 0 –2 –4 20

40

60

80

100

Atomic number

Figure 1.1 Relative abundances of the elements in the universe plotted against atomic number.

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Origin and Development of the Earth 3 Several questions have been raised about the authenticity of this hypothesis, the first having to do with the relative abundance of elements and iron. There are no stable atoms of mass 5 or 8 and the abundance of iron is greater than the smooth curve would suggest. The second is concerned with the effects of the cataclysmic explosion. If such an immense explosion occurred, why is there no mark on the universe as a result? This question may have been answered, at least in part, by the 1978 Nobel Prize winners in astronomy, Dr. Arno Penzias and Dr. R. W. Wilson (1965), who discovered a faint glow of radiation throughout the universe that could be the aftereffects of the Big Bang.

Stages of Star Development The stages of star development are an observed fact. Gas clouds comprise a large percentage of the matter in the universe. A rotating volume of gas will take on a flattened shape and a spiral will form as a direct consequence of its rotation. As the gas cloud rotates, masses tend to grow by gravitational attraction and, eventually, large masses of about equal size (protostars) will appear. These protostars are not true stars in the sense that they do not give off light. Condensation finally produces dense bodies that begin to glow with light as temperatures reach 1 million °C and their hydrogen undergoes fusion. An initial volume of gas must be compressed (reduced) about a million times to become a star, so that stars in a typical galaxy are separated by great distances.

In the Milky Way, the average distance between stars is about 4.3 light-years.

A supernova is the massive explosion of a star, producing the greatest explosion that occurs in space. It happens at the end of a star’s lifetime, when the star runs out of nuclear fuel and mass flows into its core. The core collapses, producing a giant explosion. Elements with high atomic numbers are generated by the explosion and are hurled out into space.

By this process, a black hole with an extremely high gravitational attraction is created.

Supernovas apparently occur often enough to provide a suitable source of heavy elements for the universe. The abundance and range of heavy elements and related isotopes found on Earth suggests that the matter comprising our solar system has been through at least one supernovation. The Sun, then, is apparently a second- or third-generation

star. In fact, several supernovas have been observed in the Milky Way—for example, in 1054, 1572, and 1604—and each, for a time, was much brighter than any planet. No similar events have occurred in the Milky Way since the telescope was invented. However, since 1885, nearly 80 bright supernovas have been observed by telescope beyond the Milky Way.

Origin of the Solar System The Sun has a family of eight planets and one dwarf planet. The solar system also includes an asteroid belt, which consists of numerous irregularly shaped bodies that lie between the orbits of Mars and Jupiter. The distances from the Sun of the various planets range from 0.4 AU to almost 40 AU and their periods of revolution around the Sun are as short as 88 days (Mercury) and as long as 248.4 years (Pluto). An astronomical unit (AU) is the average distance from the Earth to the Sun, equal to 1.5 × 108 km (9.3 × 107 mi) (Figure 1.2).

A growing body of information, based on recent studies and space probes, now provides a detailed description of the solar system. As in our discussion on the origin of the universe, we begin by listing the facts about the solar system. Any hypothesis must be consistent and explain the known facts about the solar system. These facts are as follows: 1. All the planets revolve around the Sun in elliptical but almost circular orbits that lie nearly in the same plane, and most of the moons revolve in the same direction. Pluto, a dwarf planet only onefifth the diameter of the Earth, has a very eccentric orbit around the Sun. 2. All planets, except for Uranus, rotate in the same direction as they revolve around the Sun, counterclockwise as one views the Earth from the north. Uranus rotates in a clockwise direction.

3. The planets seem to be spaced at regular intervals from the Sun. The Titius–Bode rule was proposed to explain the geometric progression in the distances of planets from the Sun. Stated verbally, the progression is obtained by writing 0, then 3, and continuing the progression by doubling the previous number to obtain 0, 3, 6, 12, 24, 48, 96, and so forth. Adding 4 to each number in the series yields 4, 7, 10, 16, 28, 52, 100, and so forth.

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4 Chapter One AU

1010 Pluto Neptune

39.4 30.6

3 × 109 Uranus

Saturn

19.2

9.5

109 5.2

Jupiter Asteroid Belt

2.7 avg.

Mars

1.52

3 × 108

1.0

Earth

0.72

Venus

108

0.39

Mercury Distance from the Sun (km)

3 × 107

≈ 0

Sun

Bodies not to scale

0

Figure 1.2 The planets, their sizes, and distances from the Sun.

Finally, dividing each number by 10, we get 0.4, 0.7, 1.0, 1.6, 2.8, 5.2, 10, and so forth. This is the approximate distance from the Sun in astronomical units for the planetary orbits. Both Neptune and Pluto deviate from this sequence.

4. Ninety-nine percent of the mass of the solar system is in the Sun but 98% of the angular momentum is in the planets (angular momentum = mass × angular velocity = mass × velocity × distance from center of rotation). Angular velocity is the rate of movement along a path measured as an angle from the center.

5. The terrestrial, or inner, planets (Mercury, Venus, Earth, Mars) are small, dense planets (4 to 5.5 times that of water) and the outer planets (gas or giant planets) have low densities (0.7 to 1.7 times that of water). The outer planets are more similar to the Sun than to the terrestrial planets.

Nebular Hypotheses In general, the various hypotheses that have been proposed to explain the origin of the solar system fall into two groups. The first requires a catastrophic event, the accidental intervention of another star, to

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Origin and Development of the Earth 5 explain the observed facts. These are the so-called “second-body” or “collision” hypotheses. The other group, known collectively as “single-body theories,” requires no influences beyond the Sun or solar system to explain the observed facts. Over time, the twobody hypothesis has been discarded because of the low probability of a two-star encounter and the difficulty of a filament of matter to collapse into planets.

After years of discussion and proposals on the origin of the solar system, the single-body hypothesis is preferred. Now termed the nebular or Kant– Laplace hypothesis (Murray and Dermott, 1999; Freedman, 2013), it suggests that a mass of gas cooled and began to contract. As it did, its rotational speed increased, much like skaters can increase their speed when spinning by drawing their arms inward.

This is a consequence of the law of conservation of angular momentum. Rings of gases spun off from the center and condensed to form the planets.

Interstellar matter is distributed widely throughout space. In this vast region, rarified matter exists that is about 99% gas and 1% dust. The gases are the ever-present hydrogen and helium, and the dust-size particles have compositions similar to terrestrial material. These include silicon compounds (silicates), iron oxides, ice crystals, and a host of other small molecules and compounds, including some organic compounds.

Light pressure from the stars supposedly causes this matter to consolidate to form a cloud about 9600 billion km (6000 billion mi) in diameter. As the cloud condenses it begins to rotate faster and faster. The rotation increases as it collapses slowly under its own gravity until it reaches a diameter of about 5900 million km (3700 million mi) and then collapses rapidly, perhaps in a few hundred years. The increased pressure of the contracting cloud greatly increases the temperature until it reaches about 1 million °C and nuclear fusion begins. The sun begins to radiate as a star and the planets and satellites are derived from minor dust streams in the original cloud before the last stages of collapse occur.

The nebular hypothesis leaves two important features of the solar system unexplained: the spacing of the planets from the Sun and the angular momentum of the Sun and the planets. From research conducted

by Fred Hoyle in 1960 and other related studies, the process of magnetic coupling has been presented to explain the angular momentum problem.

Magnetic Coupling Magnetic coupling is explained in the following way. Stars are known to have magnetic fields that extend into surrounding space. During formation of the solar system, the more rapidly rotating Sun dragged the less rapidly rotating disk of dust with it.

The linkage between the Sun and rotating dust provided a rotating solar magnetic field. Interaction occurred with the gases whose particles served as tiny magnets. The Sun’s angular momentum was transferred to the rotating disk of dust. This increased rotation hurled the gaseous portion to the outer reaches of the solar system where it condensed into the great planets. With this outflow of gases, the remaining particles near the Sun consisted mostly of the heavier materials, iron, silicon, and magnesium oxides. These formed into the small terrestrial planets by collision and gravitational attraction (Hoyle, 1960).

There is also some question about whether magnetic coupling completely answers the complicated aspects of how the Sun slowed its rotation and how the planets incorporated the additional angular momentum. These details require further study.

Spacing of the Planets The spacing of the planets around the Sun still remains to be fully explained. The Titius–Bode rule, discussed earlier, has been proposed as an explanation for planet spacing. It is described as the approximate doubling rule, as each planet is between 1.4 and 2.0 times further away from the Sun than its inside neighbor. Pluto’s position does not fit the rule but, as Pluto is no longer considered to be a planet, this can be excluded from consideration. However, the current consensus is that the Titius–Bode rule is not a good enough fit and an accurate explanation has yet to be proposed.

Finally, regarding the two-body hypothesis, it is more likely that a double star, rather than a single star, would approach the Sun as double stars are much more common. About 1 star in 100, such as the Sun, is a single star. Also, it is dynamically unlikely that double stars are capable of holding planets.

The Milky Way The Milky Way is a spiral-shaped galaxy with two arms extending from its central mass (Marshak, 2013). The diameter of the nebula is about 100,000

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6 Chapter One light-years and the Sun is located about 3/5 the distance from the center (30,000 light-years) in one of the spiral arms. If viewed along its central plane, the galaxy would appear as a flattened disc with a central bulge (Figure 1.3a). The central bulge is about 30,000 light-years thick. In the spiral arms that dimension reduces to about 10,000 light-years. A photograph of a spiral galaxy, found in Ursa Major (the Big Dipper), and located about 4.2 million light-years from Earth, is shown in Figure 1.3b.

In the Milky Way, our galaxy, there are 100 to 400 billion stars. It is estimated that the number of single stars is 4 × 109. Considering the needs of heat supply, light, size, age, and other requirements, stars with planets similar to the Earth would range from 1 in 1000 to 1 in 1 million but there are about 200 billion galaxies in the universe.

The nearest stars to the Sun are in the Alpha Centauri star system, which can be observed in the Southern Hemisphere. They are about 4.3 light-years away, which is the average distance between stars in the Milky Way. Stars in the galaxy rotate slowly about the central mass, and it takes the Sun and its planets about 200 million years to complete one rotation.

On a clear night, the Milky Way can be seen in a band that stretches across the sky. During the summer, our view from Earth is toward the star Sagittarius and the center of the galaxy. In the winter, the view is away from the center and toward the outer portions, along the spiral arm of the Milky Way.

The Likelihood of Life on Other Planets In the Milky Way there are from 1000 to 1 million planets on which humanlike forms could exist.

Despite the apparent abundance of planets that could conceivably support life, we must remember that distances in space are extremely vast. The minimum distance between such planetary systems is measured in distances of tens of light-years or in units of billions of kilometers or miles. These distances are obviously much beyond the capability of human travel in the foreseeable future.

A number of conditions are necessary before a planet can support life-forms as advanced as humans.

The primary requirements include the proper temperature, amount of light, gravity, atmospheric composition and pressure, and water. Other require-

ments, perhaps of lesser significance, involve other life-forms present, wind velocity, dust, and radioactivity. Some conditions that might make a planet uninhabitable are excessive meteorite bombardment, extensive volcanic eruptions, high frequency of earthquakes, and possibly an extreme level of electrical activity (lightning). Consequently, planets must meet some major requirements in order for them to be inhabitable by life-forms similar to humans: • Mass of planet: Must be greater than 0.4 Earth mass to produce and retain a breathable atmosphere and less than 2.35 Earth mass since surface gravity must be less than 1.5 g. The mass of the Earth is approximately 6 × 1024 kg.

• Period of rotation: Must be less than about 96 hours (4 Earth days) to prevent excessively high daytime temperatures and excessively low nighttime temperatures.

• Age of the planet and star about which it orbits: Must be greater than 3 billion years to allow for the appearance of complex life-forms and the production of a breathable atmosphere.

• Axial inclination or inclination of equator to the plane of orbit and level of illumination from its sun: These determine the temperature patterns on the surface. Illumination at low inclinations should lie between 0.65 and 1.35 times the Earth’s norm (between 10 and 20 lumens/cm2). However, certain combinations of illumination up to 1.9 times the Earth’s norm and inclinations up to 81° are compatible under marginal conditions.

• Orbital eccentricity: Must be less than about 0.2 because greater amounts of eccentricity produce unacceptably extreme temperature effects on the planetary surface.

• Mass of the star: Must be less than 1.43 solar mass, because residence time on the main sequence of stars must be more than 3 billion years. Solar mass is the mass of the Sun. It is equal to 3.35 × 105 Earth mass or 2.01 × 1030 kg. Mass also must be more than 0.72 solar mass because smaller stars yield an incompatibility between acceptable illumination levels and tidal retardation of a planet’s rotation.

For the rare class of planets with extremely large or close satellites, the lower range of the star’s mass is extended to 0.35 solar mass.

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Origin and Development of the Earth 7

(a)

(b) Figure 1.3 (a) The Milky Way from the side showing the location of the solar system. (Produced by the European Southern Observatory.) (b) Photograph of a spiral galaxy in Ursa Major, distance about 4.2 million light-years.

(Courtesy of the National Optical Astronomy Observatory/AVRA Image Library.)

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