Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica
Subglacial meltwater facilitates rapid ice flow beneath concurrent ice sheets, and there is widespread evidence for a dynamic subglacial water system beneath the Antarctic Ice Sheet. It steers and affects the pattern of ice flow and is a direct result from boundary processes acting at the base of th...
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ftawi:oai:epic.awi.de:39057 2023-05-15T13:40:27+02:00 Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica Kuhn, Gerhard Hillenbrand, Claus-Dieter Kasten, Sabine Smith, James A. Nitsche, Frank O. Klages, Johann Philipp 2015 https://epic.awi.de/id/eprint/39057/ http://isaes2015goa.in/docs/XII%20ISAES%202015%20Abstract%20Volume.pdf https://hdl.handle.net/10013/epic.46343 unknown Kuhn, G. orcid:0000-0001-6069-7485 , Hillenbrand, C. D. , Kasten, S. orcid:0000-0001-7453-5137 , Smith, J. A. , Nitsche, F. O. and Klages, J. P. orcid:0000-0003-0968-1183 (2015) Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica , XII International Symposium on Antarctic Earth Sciences, Goa, India, 13 July 2015 - 17 July 2015 . hdl:10013/epic.46343 EPIC3XII International Symposium on Antarctic Earth Sciences, Goa, India, 2015-07-13-2015-07-17 Conference notRev 2015 ftawi 2021-12-24T15:40:51Z Subglacial meltwater facilitates rapid ice flow beneath concurrent ice sheets, and there is widespread evidence for a dynamic subglacial water system beneath the Antarctic Ice Sheet. It steers and affects the pattern of ice flow and is a direct result from boundary processes acting at the base of the ice sheet, i.e. pressure induced basal melting. Consequently, the occurrence of subglacial meltwater plays an important role in bedrock erosion, subsequent resedimentation, and in shaping the topography of icesheet beds. Here we present new geological and geochemical data from sediments recovered on the West Antarctic continental shelf in Pine Island Bay that we interpret as reliable indicators for deposition in a palaeosubglacial lake beneath the formerly expanded West Antarctic Ice Sheet, presumably during or following the Last Glacial Maximum. Characteristic changes of sedimentary facies and geochemical profiles within these cores taken on RV Polarstern expeditions ANTXXIII/ 4 (2006) and ANTXXVI/ 3 (2010) support the presence of an active subglacial lake system during the late stages of the last glacial period. These findings have important implications for palaeo icesheet dynamics, suggesting there was considerable water available to lubricate the bedrockice interface and deposit water saturated subglacial sediments (soft tills). Based on our investigations performed so far, we suggest that the transition from subglacial lake to contact with the ocean took place in the early Holocene. During this time, we speculate, that the ice sheet thinned and successively transformed into an ice shelf with subice cavities flushed by tidal currents. Based on bathymetric maps and relative sea level curves we will aim to estimate ice thickness as the grounding line retreated across the subglacial lake threshold further inland. Our findings may also have implications for ice sheet models, which have to consider the predominantly nonlinear effects related to subglacial hydrology. Conference Object Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Bay Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic The Antarctic West Antarctic Ice Sheet Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) Island Bay ENVELOPE(-109.085,-109.085,59.534,59.534) Pine Island Bay ENVELOPE(-102.000,-102.000,-74.750,-74.750) |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Subglacial meltwater facilitates rapid ice flow beneath concurrent ice sheets, and there is widespread evidence for a dynamic subglacial water system beneath the Antarctic Ice Sheet. It steers and affects the pattern of ice flow and is a direct result from boundary processes acting at the base of the ice sheet, i.e. pressure induced basal melting. Consequently, the occurrence of subglacial meltwater plays an important role in bedrock erosion, subsequent resedimentation, and in shaping the topography of icesheet beds. Here we present new geological and geochemical data from sediments recovered on the West Antarctic continental shelf in Pine Island Bay that we interpret as reliable indicators for deposition in a palaeosubglacial lake beneath the formerly expanded West Antarctic Ice Sheet, presumably during or following the Last Glacial Maximum. Characteristic changes of sedimentary facies and geochemical profiles within these cores taken on RV Polarstern expeditions ANTXXIII/ 4 (2006) and ANTXXVI/ 3 (2010) support the presence of an active subglacial lake system during the late stages of the last glacial period. These findings have important implications for palaeo icesheet dynamics, suggesting there was considerable water available to lubricate the bedrockice interface and deposit water saturated subglacial sediments (soft tills). Based on our investigations performed so far, we suggest that the transition from subglacial lake to contact with the ocean took place in the early Holocene. During this time, we speculate, that the ice sheet thinned and successively transformed into an ice shelf with subice cavities flushed by tidal currents. Based on bathymetric maps and relative sea level curves we will aim to estimate ice thickness as the grounding line retreated across the subglacial lake threshold further inland. Our findings may also have implications for ice sheet models, which have to consider the predominantly nonlinear effects related to subglacial hydrology. |
format |
Conference Object |
author |
Kuhn, Gerhard Hillenbrand, Claus-Dieter Kasten, Sabine Smith, James A. Nitsche, Frank O. Klages, Johann Philipp |
spellingShingle |
Kuhn, Gerhard Hillenbrand, Claus-Dieter Kasten, Sabine Smith, James A. Nitsche, Frank O. Klages, Johann Philipp Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica |
author_facet |
Kuhn, Gerhard Hillenbrand, Claus-Dieter Kasten, Sabine Smith, James A. Nitsche, Frank O. Klages, Johann Philipp |
author_sort |
Kuhn, Gerhard |
title |
Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica |
title_short |
Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica |
title_full |
Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica |
title_fullStr |
Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica |
title_full_unstemmed |
Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica |
title_sort |
late glacial sub glacial lake sediments recovered and sampled in pine island bay, antarctica |
publishDate |
2015 |
url |
https://epic.awi.de/id/eprint/39057/ http://isaes2015goa.in/docs/XII%20ISAES%202015%20Abstract%20Volume.pdf https://hdl.handle.net/10013/epic.46343 |
long_lat |
ENVELOPE(-129.463,-129.463,58.259,58.259) ENVELOPE(-109.085,-109.085,59.534,59.534) ENVELOPE(-102.000,-102.000,-74.750,-74.750) |
geographic |
Antarctic The Antarctic West Antarctic Ice Sheet Glacial Lake Island Bay Pine Island Bay |
geographic_facet |
Antarctic The Antarctic West Antarctic Ice Sheet Glacial Lake Island Bay Pine Island Bay |
genre |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Bay |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Bay |
op_source |
EPIC3XII International Symposium on Antarctic Earth Sciences, Goa, India, 2015-07-13-2015-07-17 |
op_relation |
Kuhn, G. orcid:0000-0001-6069-7485 , Hillenbrand, C. D. , Kasten, S. orcid:0000-0001-7453-5137 , Smith, J. A. , Nitsche, F. O. and Klages, J. P. orcid:0000-0003-0968-1183 (2015) Late glacial sub glacial lake sediments recovered and sampled in Pine Island Bay, Antarctica , XII International Symposium on Antarctic Earth Sciences, Goa, India, 13 July 2015 - 17 July 2015 . hdl:10013/epic.46343 |
_version_ |
1766134730907975680 |