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Glacial Flooding & Disaster Risk Management Knowledge Exchange and Field Training July 11-24, 2013 in Huaraz, Peru HighMountains.org/workshop/peru-2013

What prevents  to  make  a  reliable  long-­‐term  forecast  of  glacial   and  climatic  changes  in  Central  Asia?  Paleoglaciological  base   for  long-­‐term  forecasting  from  new  starting  positions  by  the   example  of  the  Tien  Shan,  Pamir  and  Himalayas   Vladimir  I.  Shatravin   Tien  Shan  High-­‐Mountain  Scientific  Center  of  National  Academy  of  Sciences  of  the  Kyrgyz   Republic   E-­‐mail:  Shatravin@yandex.ru   What  prevents  to  make  a  reliable  long-­‐term  forecast  of  glacial  and  climatic  changes   in  Central  Asia?            Deep  contradictions  which  have  place  in  quaternary  geology  and  paleoglaciology   prevent  from  making  a  reliable  long-­‐term  forecast.  During  INQUA  (International  Union  for   Quaternary  Research)  in  1957  was  made  a  conclusion:  “The  request  on  stratigraphic  scale   of  Quaternary  period  sent  to  22  countries  received  22  different  responses”,  and  in  Congress   hold  in  1973  was  stated  that  the  situation  did  not  change  to  a  better  [1].  By  now,  40  years   later,  the  situation  did  not  become  better.  Definitely  this  is  the  result  of  deep   contradictions,  if  they  are  not  eliminated  then  all  attempts  to  make  long-­‐term  forecast  will   be  perspectiveless.            Researchers  have  been  doing  paleoglacial  reconstructions  of  the  Quaternary  for  over   100  years.  However,  they  have  not  definitely  established  even  the  number  of  Pleistocene   glaciations  on  Earth,  and  have  not  clarified  the  very  nature  of  Holocene  glaciation.  Tien   Shan  and  Pamir  are  not  exception  in  this  regard.  The  existing  paleoglacial  information  for   these  regions  is  fragmentary  and  quite  contradictory.  In  general,  this  subject  is  a  big   informative  mess.            Nowadays  there  are  a  lot  of  highly  contradictive  paleoglaciological  schemes,  for  the   Holocene  inclusively.  Among  the  lasts  there  is  a  model  of  stadial  degradation  of  the   Holocene  glaciers  and  the  model  of  their  quasistationary  states,  implicating  relative   stability  of  climate  in  the  Holocene.     General  reasons  of  contradictions            We  have  established  the  general  reasons  which  are  mentioned  below:   1–  the  incorrect  genetic  typing  of  moraines  and  pseudomoraines  which  is  traditionally            carried  out.     2–  the  lack  of  reliable  absolute  datings  of  moraines.   1. Incorrect  genetic  typing  of  moraines  and  pseudomoraines  [4,  5-­‐8].  As  main climatic  and  stratigraphic  marks  of  high  mountain  regions  researchers  use  not  only  true   moraines  but  pceudomoraines,  improperly  take  them  for  moraines.  For  the  Tien  Shan,   Pamir  and  partly  for  the  Himalayas,  on  the  base  of  developed  by  us  quantitative  facial-­‐ lithological  indicators  (geochemical,  granulometric  and  others),  it  was  determined  that  all   morphological  formations  of  mountain  areas,  traditionally  taken  for  early-­‐  and  Middle   Pleistocene  moraines,  as  well  as  significant  part  of  such  formations  taken  for  Late   Pleistocene  moraines,  in  fact  are  Late  Pleistocene-­‐Holocene  pceudomoraines,  which  true  


genesis is  gravitational;  they  are  represented  by  wide-­‐spread  landslides  (by  widely   developed  landslides).  This  finding  allowed  us  to  reveal  the  very  dame  “root  of  evil”  which   makes  difficulties  and  unresolved  contradictions  during  paleoglaciological  reconstructions   of  quaternary  period,  stratigraphical  partition  and  correlation  of  quaternary  deposits  of   high  mountain  areas  with  all  ensuing  consequences  of  paleoglaciological  and  geological   direction.  We  made  such  conclusion  on  the  basis  of  pattern  regularities  determination  for   glacial  (with  formation  of  moraines)  and  gravitational  (with  formation  of  pseudomoraines)   lithogenesis.  Particularly  it  was  established  that  glacial  and  gravitational  types  of   lithogenesis  proceed  in  exactly  opposite  geochemical  conditions:  first  of  them  is  in   reductive  geochemical  conditions,  and  the  second  is  in  oxidizing  conditions.  The  photo   shows  –  examples  of  true  moraines  and  pseudomoraines.  gl  Hs  –  Holocene  moraines.  gl  Ps   III  –  Late  Pleistocene  moraines.  gr  Ps  III-­‐Hs  –  pseudomoraines  (delapsive  gravitational   developments  of  late  Pleistocene    and  Holocene  age).  Fe2+,  Fe3+      -­‐  geochemical  facies  of   ferrous  oxide  and  iron  oxide  accordingly.     Moraines  and  pseudomoraines  in  the  valley  of    Con-­‐Aksu  river  (Noth  Tien  Shan).  The   arrows  (here  and  below)  show  the  direction  and  slumping  area  of  polygenetic  slope,s   deposits  that  formed  pseudomoraines.  In  this  case  from  traditional  perspective  gr  Ps  III-­‐Hs   are  as  moraines  of  Middle  Pleistocene  age.       Pseudomoraines  in   Alay  valley  (North   Pamir).  From   traditional   perspective  they   are  as  Late   Pleistocene   moraines.        

     

  Pseudomoraines  of  the   Central  Pamir.  From   traditional  perspective  they   are  as  Late  Pleistocene   moraines.          


Pseudomoraines in   downstream  of  Muksu  velley   (North-­‐Western  Pamir).  The   symbol  gr  (dl)  shown  in   figure  is  taken  as  the  ultimate   classic  and  coastal   Pleistocene  moraines  of   Fedchenko’s  glacier.  Terraces   claim  to  be  ephemeral   terraces  of  coastal   sedimentary  moraines.  For   deposits  of  terraced   "moraines"  there  were   received  some  RTL-­‐datings  of   260-­‐180  thousand  years,   allegedly  correspond  to  the  Middle  Pleistocene.  According  to  the  facio-­‐lithological  researches  of   the  author  it  is  pseudomoraines  in  the  form  of  huge  landslide  blocked  Muksu  river;  terraces  -­‐  this   river  terraces  formed  on  the  substrate  landslides.         Moraines  and     pseudomoraines  in   Khumbu  valley   (Himalayas).      

 

 2.  About  the  lack  of  reliable  absolute  datings  of  moraines  [5-­‐8].  Traditionally  applied   physical      methods  of  absolute  dating  (14С,  TL,  OSL  and  10Ве)  do  not  allow  to  receive  reliable   dating  of    moraines.    Dating  of  pseudomoraines,  taking  for  moraines  by  mistake,  leads  to   disinformation.       Radiocarbon  method  of  dating.  Moraines  were  not  dated  by  this  method  because  in   moraines  were  not  found  necessary  autochthonous  organic  matter  and  even  there  were  no   possibilities  to  find  it  there.  Due  to  this  all  radiocarbon  datings  of  moraines  were  received   exceptionally  by  allochthonous    organic  matter  or  autochthonous,  found  not  in  moraines  but   neighboring  deposits,  not  of  glacial  genesis.  Meanwhile,  there  is  unresolved  question  –  to   what  extent  datings  are  younger  or  older  then  moraines.  Use  of  surface  soil  for  such   radiocarbon  method  leads  to  paradox.       Thermoluminescent  dating  of  moraines.  Thermoluminescent  dating  of  moraines  (as  well  as   received  by  the  method  of  OSL,  which  represent  kind  of  TL  method)  should  be  considered  as   doubtful  according  to  the  below  mentioned  reasons:     -­‐  the  very  method  of  TL-­‐dating  is  at  the  development  stage,  and  it  is  developed  exclusively  for   loess  deposits;  


-­‐ according  to  interlaboratory  control  tests,  the  margin  of  error  of  this  method  comes  up  to   300-­‐400%  ;   –  except  datings  variations  there  is  significant  overstating  (can  be  more  in  10  times)  of  ages   towards  C-­‐14  datings;     – the  main  and  absolutely  insurmountable  disadvantage  of  TL  and  OSL-­‐methods  of  dating    is   uncertainty  of  “null  moment”  from  which  dated  time  of  underground  disposal  (from  radial   cosmic  energy)  of  material  for  such  dating  (quartz  or  feldspathic  grains).       Method  of  cosmic  isotopes  (10Ве).  Impracticability  of  this  method  for  dating  of  mraines  also   determined  by  “null  moment”.              Therefore,  the  use  of  such  dates  is  only  producing  more  mess  in  this  subject.     How  to  eliminate  reasons  of  contradictions?     1. Difference  between  moraines  and  pseudomoraines  [3,  4].  For  reliable  differentiation  of   moraines  from  pceudomoraines  we  received  genetic  features  of  these  sediments  in  the  form   of  quantitative  facial-­‐lithological  indicators  (geochemical,  granulometric).  In  order  to   differentiate  moraines  from  pseudomoraines  of  mountain  areas  we  have  received  reliable   genetic  traits  of  these  deposits  in  the  form  of  the  below  indicated  quantitative  facio-­‐ lithological  figures.       Geochemical  figures.  Iron  oxide/protoxide  ratio  (protoxidic  coefficient  on  ferrum)  К=   Fe2O3/FeO   These  figures  are:   - moraines                        К  =  0,03  -­‐:  0,07   - pseudomoraines  К  =  0,3  -­‐:  1,0       Granulometric  figures.  Degree  of  clay  content  S=<0,005/(1-­‐0,005)  –  correlation  of  fractions   percentage  <0,005  mm  and  1  -­‐  0,005  mm,  where  <0,005  mm–  clay  fraction,  1  -­‐  0,005  (mm).   These  figures  are:   - Holocene  moraines        S=  0,078   - Pleistocene  moraines  S=  0,107   - pseudomoraines                  S=  0,159       True  to  type  exposure  of   moraine  and   pseudomoraine.   Moraine  deposits  are  of   blue  and  whitish  color,   which  corresponds  to   geochemical  facies  of   2+ ferrous  iron  (Fe ).  The  deposits  of  pseudomoraine  are  of  red-­‐brown  color,  which  corresponds   to  geochemical  facies  of  iron  oxide  (Fe3+).     Mineral  grains  of  moraines   (Fe2+)  and  pseudomoraines   (Fe3+)  under  the  microscope.   Increased  of  80  -­‐and  10-­‐fold   accordingly    


2. The establishment  of  reliable  absolute  ages  of  moraines  [5,  7-­‐9].  In  order  to   receive  reliable  absolute  age  of  moraines  we  have  developed  the  method  of   radiocarbon  dating  of  moraines  with  the  use  of  autochthonous  organic  matter.  In   moraines  we  have  found  autochthonous  glacio-­‐chionophilous  (special  glacial)  fine-­‐ dispersed  organics  disseminated  in  fine-­‐grained  morainic  material;  its  nature  was   identified  and  shown  the  possibilities  for  this  organic  usage  for  radiocarbon  dating   of  moraines.  It  should  be  mentioned  that  the  selection  of  samples  by  this  method  for   radiocarbon  dating  of  moraines  is  very  effortful:  in  order  to  select  own  sample  it  is   necessary  to  carry  out  excavation  in  moraine  attaining  several  cubic  meters.   However,  there  are  no  alternatives  for  this  method  of  moraines  dating.  

New starting  positions  in  paleoglaciology  and  Quaternary  Geology                        The  correct  genetic  typing  of  moraines  and  pseudo-­‐moraines  and  the  method  of  reliable   14С  dating  of  moraines  together  make  the  new  starting  positions  in  paleoglaciology  and   Quaternary  Geology.       Settled  pattern  regularities   1. The  resulting  facial-­‐lithological  data  present  strict  correlative  and  paleoclimatic   criteria  [4,  6,  7].  It  has  been  found  that  during  the  genetic  transformation  of  moraine  and   pseudo-­‐moraine  deposits  into  alluvial/proluvial  deposits,  the  oxide/protoxide  ratio  and   clay  content  of  the  original  deposits  are  well  preserved.                2.  In  the  Tien  Shan,  Pamir  and  Himalaya  there  was  only  one  Pleistocene  glaciation,  and  it   took  place  in  the  Late  Pleistocene  epoch  [4,  6].  There  are  three  major  stages  in  it.  One  must   note  that  in  the  Tien-­‐Shan  and  Pamir,  the  alluvial/proluvial  deposits  of  the  Early  and   Middle  Pleistocene  show  extremely  high  values  of  oxide/protoxide  ratio,  i.e.  they  belong  to   the  geochemical  facies  of  ferric  iron.  The  use  of  these  criteria  allowed  to  establish  definitely   that  there  was  only  one  Pleistocene  glaciation  in  the  Tien-­‐Shan  and  Pamir,  and  it  occurred   in  the  late  Pleistocene.  There  are  three  main  stages.   3.  Morpho-­‐litho-­‐  and  stratigraphically  pattern  regularity  expressed  in  joining  moraines  and   pseudomoraines.  

Conceptual  scheme  of  morpho-­‐lithostratigraphic  segmentation  of  generations  of  late   Pleistocene  and  Holocene  glaciations  and  massive  delapsive  gravitational  formations  in  the   Tien  Shan.   gl  Ps  I,  gl  Ps  II  and  gl  Ps  III  –  late  Pleistocene  moraines  of  the  1st,  2nd,  and  3rd  generations,   accordingly.   gr  –  delapsive  gravitational  formations  (pseudo-­‐moraines).     1-­‐  7  –  morphologically  well-­‐articulated  Holocene  moraines  of  the  1st,  2nd,  3rd,  4th,  5th,  6th,   and    7th,      generations  accordingly.  


4. Morphologically expressed  regularity  disintegration  of  the  Holocene  glaciation  [4,  5,   9].  On  the  example  of  the  Tien-­‐Shan,  Pamir  and  the  Himalayas  we  found  out  that  Holocene   glaciation  disintegrates  stadialy  by  the  principle  of  dying  oscillations.  It  distinguishes  7   main  stages.  The  following  radiocarbon  dating  were  received  for  the  first  three  stadial   moraines  of  Holocene  glaciations  of  one  of  moraine-­‐glacial  complex  of  the  Tien-­‐Shan:    I       stage–  8000  years,  II  stage  –  5000  years,  III  stage–  3400  years.  On  the  base  of  the  received   data  we  offered  the  scheme  of  stadial  degradation  of  the  Holocene  glaciation  in  the   mountains  of  Tien-­‐Shan.  

   

Morphologically apparent  staged  moraines  (I  -­‐VII)  in  Tez-­‐Ter  moraine-­‐glacial    complex  (Tien-­‐ Shan).  

                          Stadial  (I-­‐VI)  generations  of  moraine  -­‐glacial  complex;  Stadial  generations  of  the  Holocene;   moraine-­‐glacial  in  the  valley  of  Altyn-­‐Dara  River  complex  Duw  Glacier  (Himalayas).   (Pamir).  7th  stage  is  out  of  sight.            


Schematic model  of  Tien-­‐Shan  glaciations  degradation  in  the  Holocene   Horizontal  axis  –  time  scale  (thousands  of  years)   I,  II,  III,  IV,  V,  VI,  VII  –  glaciations  stages  related  to  morphologically  expressed  moraines  of  the   Holocene  moraine  and  glacial  complexes.  8000,  5000,  3400  –  radiocarbon  age  of  stadial   moraines,  years;    ?  –  estimated  next  stage  of  the  Holocene  glaciations              This  scheme  may  serve  as  a  paleoglaciological  basis  for  long-­‐term  forecasting  of  glacial  and   climatic  changes  of  Central  Asian  mountain  areas.  The  last  shaft  on  this  schematic  model   (located  beyond  zero  age  mark)  is  extrapolative  by  forecasting,  taking  into  account  really   observed  regularities.  It  represents  the  greatest  interest  in  long-­‐term  forecasting  of  glacial   and  climate  changes,  as  on  its  amplitude  (future  next  splash  of  modern  glaciation),  starting   time  and  duration  will  depend  climate  and  glaciation  in  foreseeable  future  not  only  of  the   Tien-­‐Shan,  but  the  whole  Central  Asian  region.  The  dating  of  the  other  stadial  moraines  –  is  a   way  to  long-­‐term  forecast  of  glacial  and  climatic  changes.              For  more  detailed  paleoglaciological  reconstruction  of  the  Holocene  glaciation  radiocarbon   dating  should  be  combined  with  isotope-­‐oxygen  (basing  on  ratio  of  isotopes  18О/16О)   investigation  of  glaciers.  However,  a  weak  point  of  the  isotope-­‐oxygen  studying  of  glaciers  is   definition  of  absolute  age  of  ice  cores.  It  is  performed  with  the  use  of  ratio-­‐based  models  of   age  and  depth  of  glacial  thicknesses,  constructed  on  the  basis  of  characteristics  of  flow.  The   method  of  radiocarbon  dating  of  moraines  we  offer  allow  to  date  the  isotope-­‐oxygen   temperature  curve  of  past  received  during  drilling  of  mountain  glaciers,  that  is  to  adhere  it  to   reliable  age  scale  [7,  8].  For  this  purpose,  it  is  necessary  to  select  series  of  samples  on  contacts   of  glacial  ice  and  a  superficial  (ablative)  moraine  covering.  Samples  of  ice  will  be  used  for   isotope-­‐oxygen  analyses  and  samples  of  autochthonic  organic  substance  from  moraines  will   be  used  for  radiocarbon  dating.   Conclusion            Studies  of  paleo-­‐glaciology  and  quaternary  geology  are  closely  connected.  Due  to  incorrect   genetic  typing  of  moraines  and  pseudomorains  and  the  lack  of  reliable  absolute  dating  of   moraines  paleoglaciology  and  Quaternary  geology  now  find  themselves  without  reliable   climate-­‐stratigraphic  benchmarks,  which  makes  further  research  in  this  field  hopeless.  The   situation  should  be  viewed  as  a  deadlock.  That  is  why  based  on  all  of  the  above  it  can  be   concluded  that:   We  must  break  the  current  impasse  in  paleo-­‐glaciology  and  quaternary  geology  instead  of   waiting  for  decades  when  supposedly  “quantity  will  be  transformed  into  quality.”            Today  people  need  reliable  long-­‐term  forecast  of  glaciation  and  climate,  and  this  problem  is   getting  more  and  more  acute.  The  only  way  to  overcome  difficulties  and  get  the  necessary  


result quickly  enough  is  to  start  conducting  paleo-­‐glaciological  reconstructions  and  geological   study  of  quaternary  period  with  the  new  starting  positions  (basing  on  quantitative  facial   lithologic  indicators  and  reliable  absolute  dating).  The  answer  to  a  question  “What  prevents   from  doing  this”  may  be  as  follows:  besides  objective  reasons,  revealed  in  this  report  as  well   as  our  researches  data  (www.glaciology.ru,  www.scorcher.ru/glaciology/index.php),   subjective  reasons  –  conservatism  of  scientists  –  take  place.       References     1. Bowen  D,  1981.  Quaternary  Geology.  «Mir»,  Moscow.   2. Shatravin  VI,  1994a.  Facial-­‐lithological  typification  of  main  genetic  generations  of   Quaternary  deposits  of  high-­‐mountain  zones.  In:  Geology  of  the  Cenozoic  and  seismotectonic   of  the  Tien-­‐Shan.  «Ilim»,  Bishkek.  3-­‐15.   3. Shatravin  VI,  1994b.  General  regularities  of  glacial  and  gravitational  types  of  lithogenesis   of  mountainous  areas  In:  Geology  of  the  Cenozoic  and  seismotectonic  of  the    Tien-­‐Shan.   «Ilim»,  Bishkek.  15-­‐26.   4. Shatravin  VI,  2007a.  Reconstruction  of  Pleistocene  and  Holocene  glaciations  in  the  Tien-­‐ Shan  from  new  starting  positions.  In:  Climate,  Glaciers  and  Lakes:  Journey  to  the  Past.  “Ilim”,   Bishkek.  26-­‐46.   5. Shatravin  VI,  2007b.  Radiocarbon  dating  of  moraines  with  the  use  of  dispersed  organics.   In:  Climate,  Glaciers  and  Lakes:  Journey  to  the  Past.  “Ilim”,  Bishkek.  74-­‐92.   6. Shatravin  VI,  Tuzova  TV,  2010.  New  Starting  Positions  in  Paleoglaciological   Reconstructions  at  Long-­‐Term  Forecasting  of  Eurasia  Glaciation  and  Climate.  In:  Collection   of  Scientific  Papers  No  65,  dedicated  to  the  memory  of  Academician  Mirtckhlava  C.E.  Tbilisi.   240-­‐244.   7. Shatravin  VI,  Tuzova  TV,  2011a.  Long-­‐Term  Forecast  of  Glaciation  and  Evaluation  of   Glacial  Resources  of  Central  Asia  with  Use  of  Isotopic  Methods  In:  AASA  Regional  Workshop   on  “The  Roles  of  Academies  of  Sciences  in  Water  and  Energy  Problems  in  Central  Asia  and   Ways  for  Their  Solution»,  NAS  KR,  Bishkek.  85-­‐90.   8. Shatravin  VI,  Tuzova  TV,  2011b.  Long-­‐Term  Forecast  of  Glaciation  and  Evaluation  of   Glacial  Resources  of  Central  Asia  with  Use  of  Isotopic  Methods.  Journal  «Izvestiya  of  the   National  Academy  of  Sciences  of  the  Kyrgyz  Republic».  Series  of  physics  and  technical,   mathematical,  mining-­‐and-­‐geological  sciences.  NAS  KR,  Bishkek  2(4):  24-­‐27.   9. Shatravin  VI,  2012.  Establishment  of  regularity  of  disintegration  of  the  Holocene   glaciations  through  radiocarbon  dating  of  dispersed  organic  matter  from  moraines.  In:   Andean-­‐Asian  Mountains  Global  Knowledge  Exchange  On  Glaciers,  Glacial  Lakes,  Water  &   Hazard  Management.  Field  Expedition  to  Imja  Glacial  Lake.  September  3-­‐24.  ICIMOD,   Katmandu.  123-­‐125.    

Vladimir Shatravin: Paleoglaciological base for long-term forecasting in Tien Shan, Pamir & Himalaya  

Deep contradictions which have place in quaternary geology and paleoglaciology prevent from making a reliable long-term forecast. During INQ...

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