Abstract Quantifying the contribution of the East Antarctic Ice Sheet (EAIS) to sea-level rise during the last deglaciation is complicated by the limited opportunities to constrain ice-sheet models. The nunatak, Escalade Peak, provides a gauge for past ice surface elevation changes and behaviour throughout the last glacial cycle. Geomorphological mapping, geological evidence and 10Be cosmogenic-nuclide exposure dating at Escalade Peak, provide new constraints on the ice surface history of the Skelton Neve since the Last Glacial Maximum (LGM). An elevation transect from the eastern margin of Escalade Peak indicates that the ice surface of the Skelton Neve was at least 50 m and perhaps >120 m higher than present during the LGM. In contrast, surface-exposure ages from a suite of inner moraines (blue-ice moraines) adjacent to Escalade Peak do not provide independent ice surface elevation constraints, but may provide an indirect constraint on the timing of thinning due to exhumation-ablation processes. Maximum simple exposure ages from the inner moraines suggest ice surface ablation was initiated by 19.2 ka, but the majority of ice surface lowering at Escalade Peak likely occurred after ∼15 ka and reached the present-day ice level at ∼6 ka. These findings suggest that slow flowing inland sites of EAIS outlet glaciers, such as southern Skelton Neve, experienced minimal ice surface elevation change since the LGM and record an EAIS outlet glacier and western Ross Sea retreat signature rather than widespread Ross Sea retreat. The ice surface lowering is likely to have been in response to retreat of the grounded ice in the western Ross Embayment causing a reduction in buttressing of the Skelton Glacier and draw down into the Ross Sea.

中文翻译：

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自末次盛冰期以来，横贯南极山脉斯凯尔顿冰川的冰面降低：对罗斯海西部接地冰退缩的影响

摘要 由于限制冰盖模型的机会有限，量化南极东部冰盖 (EAIS) 在最后一次冰消期间对海平面上升的贡献变得复杂。努纳塔克山，Escalade Peak，提供了一个衡量过去冰面海拔变化和整个最后一个冰川周期的行为的标准。埃斯卡莱德峰的地貌图、地质证据和 10Be 宇宙成因核素暴露年代测定为自末次盛冰期 (LGM) 以来斯凯尔顿尼夫冰面历史提供了新的限制。Escalade 峰东缘的高程断面表明，Skelton Neve 的冰面比 LG​​M 期间的冰面至少高 50 m，甚至可能超过 120 m。相比之下，与 Escalade 峰相邻的一组内部冰碛（蓝冰冰碛）的表面暴露年龄不提供独立的冰面高程约束，但可能对由于剥脱-消融过程而变薄的时间提供间接约束。来自内部冰碛的最大简单暴露年龄表明冰面消融始于 19.2 ka，但 Escalade 峰的大部分冰面下降可能发生在约 15 ka 之后，并在约 6 ka 时达到当今的冰位。这些发现表明，EAIS 出口冰川的缓慢流动的内陆地点，例如 Skelton Neve 南部，自 LGM 以来经历了最小的冰面海拔变化，并记录了 EAIS 出口冰川和西罗斯海后退的特征，而不是广泛的罗斯海后退。