Post‐LGM Grounding‐Line Positions of the Bindschadler Paleo Ice Stream in the Ross Sea Embayment, Antarctica

Journal of Geophysical Research F: Earth Surface - Tập 122 Số 10 - Trang 1827-1844 - 2017
Philip J. Bart1, John B. Anderson2, F. O. Nitsche3
1Department of Geology and Geophysics, E235 Howe-Russell-Kniffen Geoscience Complex Louisiana State University Baton Rouge LA USA
2Department of Earth Sciences, Rice University, Houston, TX, USA
3Lamont Doherty Earth Observatory of Columbia University 61 Route 9W Palisades NY USA

Tóm tắt

AbstractThe West Antarctic Ice Sheet (WAIS) retreated more than 1,000 km since last grounding at the Ross Sea outer continental shelf. Here we show an interpretation of former grounding line positions from a new large‐area multibeam survey and a regional grid of chirp cross‐sectional data from the Whales Deep Basin in eastern Ross Sea. The basin is a paleo‐glacial trough that was occupied by the Bindschadler Ice Stream when grounded ice advanced to the shelf edge during the Last Glacial Maximum. These new geophysical data provide unambiguous evidence that the WAIS occupied at least seven grounding line positions within 60 km of the shelf edge. Four of seven grounding zone wedges (GZWs) are partly exposed over large areas of the trough. The overlapping stratal arrangement created a large‐volume compound GZW. Some of the groundings involved local readvance of the grounding line. Subsequent to these seven outer continental shelf groundings, the ice sheet retreated more than 200 km towards Roosevelt Island on the middle continental shelf. The major retreat across the middle continental shelf is recorded by small‐scale moraine ridges that mantle the top of GZW7, and these are suggestive of relatively continuous grounding line recession. The results indicate that retreat was considerably more complex than was possible to reconstruct with reconnaissance‐level data. The added details are important to climate models, which must first be able to reproduce the recent retreat pattern in all of its complexities to improve confidence in model predictions of the system's future response.

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Tài liệu tham khảo

10.1126/science.1138396

10.1038/322057a0

10.1016/0025-3227(89)90150-3

10.1126/science.1138393

10.1017/CBO9780511759376

10.1016/j.quascirev.2013.08.020

10.1130/0091-7613(1988)016<1130:IRSSTM>2.3.CO;2

10.1016/j.palaeo.2011.08.007

10.2110/jsr.69.1276

Bart P. J. Krogmeier B. Bart M. P. &Slawek T.(2017).A two millennia long grounding event duration of the West Antarctic Ice Sheet in Ross Sea Nature Scientific Reports.

10.1016/j.quascirev.2012.04.023

10.1016/j.margeo.2011.09.005

10.1016/j.margeo.2015.02.001

10.1126/science.1087231

10.1126/science.286.5438.280

Davey F. J. &Nitsche F. O.(2005).Bathymetric grid of the Ross Sea Antarctica. Retrieved from:ftp://ftp.ldeo.columbia.edu/pub/fnitsche/RossSeaBathymetry/(2005)

Domack E. W., 1999, Late Pleistocene‐Holocene retreat of the West Antarctic Ice Sheet system in the Ross Sea: Part 2—Sedimentologic and stratigraphic signature, GSA Bulletin, 111, 1517, 10.1130/0016-7606(1999)111<1517:LPHROT>2.3.CO;2

10.1130/B30628.1

10.1130/G24808A.1

10.1016/S0277-3791(97)00070-X

10.1144/0016-764901-125

10.1016/j.quascirev.2004.10.007

10.1016/j.epsl.2006.06.044

10.1029/2009JF001482

10.1130/B30643.1

10.5194/tc-10-1003-2016

10.1111/j.1502-3885.2003.tb01431.x

10.1130/G32153.1

10.1016/j.quascirev.2011.12.017

10.1017/S0954102014000212

10.1038/ngeo1600

10.1038/ngeo581

10.1016/j.quascirev.2012.01.017

10.1016/j.geomorph.2015.05.020

10.1016/j.quascirev.2014.02.017

10.1016/j.quascirev.2013.10.016

10.1130/G25505A.1

10.1130/0016-7606(1999)111<0091:DSTAGM>2.3.CO;2

10.1130/0091-7613(1996)024<0223:COLWIR>2.3.CO;2

10.1016/j.earscirev.2011.10.003

10.1080/17445647.2013.829411

10.1017/jog.2016.18

10.1016/j.palaeo.2007.08.015

10.1016/j.quascirev.2005.12.013

10.1029/2006JF000606

Ó Cofaigh C., 2002, Evolution of subglacial bedforms along a paleo‐ice stream, Antarctic Peninsula continental shelf, Geophysical Research Letters, 29, 41–44, 10.1029/2001GL014488

10.1038/nature07809

10.1029/2006JF000664

10.1130/0016-7606(1999)111<1486:LPHROT>2.3.CO;2

10.1144/GSL.SP.2002.203.01.15

10.1002/2016JF004154

10.1002/esp.3532

10.3189/172756499781821625

10.1017/S0022143000014726

10.1017/S0954102013000199

Vanneste L. E., 1995, 97

10.1016/S0277-3791(97)00003-6

10.1016/j.geomorph.2005.05.015

10.1073/pnas.1516908113

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Journal of Geophysical Research F: Earth Surface

Tập 122 Số 10

1827-1844

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