Uncertainty regarding the sensitivity of the East Antarctic Ice Sheet (EAIS) to past climate changes strongly limits projections of future global sea-level rise. To reduce this uncertainty, we propose new geochronological constraints on EAIS oscillations following the Last Glacial Maximum (LGM) using paired cosmogenic nuclides (26Al-10Be) produced in ice-free landforms (e.g., erratic boulders and bedrock surfaces) from the Lacroix and Port-Martin sites in Terre Adélie (East Antarctica). We show two exposure-ages (10Be-26Al) clusters spanning (1) the late-Holocene for boulders-samples, and (2) the Late-Pleistocene for bedrock-samples. Boulders-samples with simple-exposure history record a Neoglacial thinning and/or retreat of the EAIS at ca. 1.4 ka for Lacroix site, and ca. 0.6 ka for Port-Martin site. Erratic boulders-samples with complex-exposure history further suggests multiple phases of ice-sheet advances in retreat since the LGM, and since the late-Pleistocene for bedrock-samples. These findings highlight (1) recent (late-Holocene) EAIS instabilities similar to observations in West Antarctica, along (2) changes in erosive and transport capacity of the EAIS following the LGM.

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