Age stratigraphy in the East Antarctic Ice Sheet inferred from radio-echo sounding horizons

摘要

The East Antarctic Ice Sheet contains a wealth of information that can be extracted from its internal architecture such as distribution of age, past flow features, and surface and basal properties. Airborne radar surveys can sample this stratigraphicarchive across broad areas. Here, we identify and trace key horizons across several radar surveys to obtain the stratigraphic information.We transfer the age–depth scales from ice cores to intersecting radar data. We then propagate these age scales across the ice sheet using the high fidelity continuity of the radar horizons.In Dronning Maud Land, including Dome Fuji, we mapped isochrones with ages of 38 and 74ka. In the central region of East Antarctica around Dome Concordia, Vostokand Dome Argus, we use isochrone ages of 38, 48, 90 and 161ka.Taking together both regions, we provide isochrone depths traced along a combined profile length of more than 40000km and discuss uncertainties of the obtained stratigraphy, as well as factors important to consider for further expansion.This data set is the most extensive distribution of internal horizons in East Antarctica to date. The isochrone depths presented in this study are available on PANGAEA (https://doi.org/10.1594/PANGAEA.895528; Winter et?al.,?2018).