Brief communication: Candidate sites of 1.5 Myr old ice 37 km southwest of the Dome C summit, East Antarctica

Passalacqua, Olivier [Université Grenoble Alpes, CNRS, IRD, IGE] Cavitte, Marie [UCL] Gagliardini, Olivier [Université Grenoble Alpes, CNRS, IRD, IGE] Gillet-Chaulet, Fabien [Université Grenoble Alpes, CNRS, IRD, IGE] Parrenin, Frédéric [Université Grenoble Alpes, CNRS, IRD, IGE] Ritz, Catherine [Université Grenoble Alpes, CNRS, IRD, IGE] Young, Duncan [University of Texas Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin] et al.[show all]

The search for ice as old as 1.5 Myr requires the identification of places that maximize our chances to retrieve old, well-resolved, undisturbed and datable ice. One of these locations is very likely southwest of the Dome C summit, where elevated bedrock makes the ice thin enough to limit basal melting. A 3-D ice flow simulation is used to calculate five selection criteria, which together delineate the areas with the most appropriate glaciological properties. These selected areas (a few square kilometers) lie on the flanks of a bedrock high, where a balance is found between risks of basal melting, stratigraphic disturbances and sufficient age resolution. Within these areas, several sites of potential 1.5 Myr old ice are proposed, situated on local bedrock summits or ridges. The trajectories of the ice particles towards these locations are short, and the ice flows over a smoothly undulating bedrock. These sites will help to choose where new high-resolution ground radar surveys should be conducted in upcoming field seasons.