Güntzel Janina janina.guentzel@awi.de 0009-0004-3713-6881 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 Müller Juliane juliane.mueller@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/juliane-mueller.html 0000-0003-0724-4131 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 Lembke-Jene Lester Lester.Lembke-Jene@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/lester-lembke-jene.html 0000-0002-6873-8533 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 Tiedemann Ralf ralf.tiedemann@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/ralf-tiedemann.html 0000-0001-7211-8049 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 Mollenhauer Gesine gesine.mollenhauer@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/gesine-mollenhauer.html 0000-0001-5138-564X Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 Klages Johann Philipp Johann.Klages@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/johann-philipp-klages.html 0000-0003-0968-1183 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 2026 Sedimentological, geochemical and sediment-physical analysis of eight sediment cores from the Mac. Robertson Shelf, East Antarctica dataset bundled publication https://doi.org/10.1594/PANGAEA.982379 2026-06-29T08:58:43 The future behavior of the Antarctic Ice Sheet is considered to be one of the largest uncertainties in global climate projections, with its stability fundamentally governed by grounding-zone processes, bed geometry, and sensitivity to oceanic forcing. However, observational records only reflect a short moment when considering the length of a full cycle of ice sheet expansion and retreat. Therefore, paleo-data present a valuable extension to the observational period. East Antarctica's deglaciation history remains largely understudied compared to the West Antarctic margin. This emphasizes the urgent need for reliable long-term spatiotemporal data on ice sheet change, particularly for sectors that play key roles in supplying the world's oceans with dense bottom water. In this study, we performed a multi-proxy analysis on geophysical and geological data recovered from two prominent glacial cross-shelf troughs on the Mac. Robertson continental shelf. We classified submarine glacial landforms on the continental shelf along both troughs from combined multibeam swath bathymetry and sub-bottom profiler data to infer past grounding line extent and the pattern of subsequent grounding line retreat. Additionally, combined sedimentological, sediment-physical, and geochemical analyses, including foraminifer radiocarbon dating, reveal the style and timing of this retreat across the shelf. Our study concludes that grounded ice reached the Mac. Robertson continental shelf break until just before ~12.7 cal. ka BP, hence preventing the formation of Dense Shelf Water (DSW) in its current form. We therefore infer a different formation mechanism for DSW as an important precursor of Antarctic Bottom Water under such full glacial conditions before continued grounding-line retreat exposed the middle continental shelf by ~10.8 cal. ka BP and set the stage for more modern-like conditions. Güntzel Janina janina.guentzel@awi.de 0009-0004-3713-6881 Müller Juliane juliane.mueller@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/juliane-mueller.html 0000-0003-0724-4131 Tiedemann Ralf ralf.tiedemann@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/ralf-tiedemann.html 0000-0001-7211-8049 Mollenhauer Gesine gesine.mollenhauer@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/gesine-mollenhauer.html 0000-0001-5138-564X Lembke-Jene Lester Lester.Lembke-Jene@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/lester-lembke-jene.html 0000-0002-6873-8533 Weigelt Estella estella.weigelt@awi.de 0000-0003-1598-456X Schopen Lasse Wesch Niklas Kattein Laura laura.kattein@awi.de Mackintosh Andrew 0000-0002-6430-4711 Klages Johann Philipp Johann.Klages@awi.de https://www.awi.de/en/about-us/organisation/staff/single-view/johann-philipp-klages.html 0000-0003-0968-1183 2026 Last Glacial Maximum extent and subsequent retreat of the East Antarctic Ice Sheet from the Mac. Robertson Shelf journal article The Cryosphere 20(7) https://doi.org/10.5194/tc-20-3739-2026 3739-3758 63.18823 65.81721 -67.142285 -66.828596 64.69917514285716 -66.97600678571428 2022-02-09T10:00:57 2022-02-10T21:34:36 14 CC-BY-4.0 Creative Commons Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ Shear strength, primary | Shear str | Hand Held Shear Vane Test | Water content, wet mass | Water wm | Calculated from mass/volume | wt. % | Carbon, organic, total | TOC | Carbon-sulphur determinator, ELTRA CS-800 | Carbon/Nitrogen ratio | C/N | Element analyser CHN | Size fraction > 2 mm, gravel | >2 mm | Wet sieving | Size fraction 2.000-0.063 mm, sand | 2000-63 µm | Size fraction < 0.063 mm, mud, silt+clay | <63 µm | Age, dated material | Dated material | Age, dated | Age dated | Accelerator mass spectrometry, Ionplus, Mini Carbon Dating System (MiCaDaS AWI) | Age, dated, standard deviation | Age dated std dev | Age, 14C calibrated | Laboratory code/label | Lab label citable Antarctic Shelf East Antarctica Polarstern Radiocarbon ages Sedimentology-marine cores method12562 method15750 method159 method17820 method21 method415 method7389 param132179 param151 param1547 param1556 param19 param2836 param35 param5506 param6165 param67 param98515 pi110819 author10824 author109934 author110819 author110820 author20400 author24586 author27669 author35356 author37212 author65542 author68763 geocode1599 geocode1600 geocode1601 inst32 journal4140 license21 ref133285 term47738 term50205 term50638 term53447 term76136