EGU21-3366 https://doi.org/10.5194/egusphere-egu21-3366 EGU General Assembly 2021 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Englacial stratigraphy in Ellsworth Subglacial Highlands, West Antarctica Felipe Napoleoni1,2, Neil Ross3, Michael J. Bentley1, Stewart S.R. Jamieson1, Andrew M. Smith2, José- Andrés Uribe4, Rodrigo Zamora4, and Alex M. Brisbourne2 1Durham University, Geography, Durham, United Kingdom of Great Britain – England, Scotland, Wales 2British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, United Kingdom of Great Britain – England, Scotland, Wales 3School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom of Great Britain – England, Scotland, Wales 4Centro de Estudios Científicos, Arturo Prat 514, Valdivia, Chile Airborne ice-penetrating radar surveys around the Ellsworth Subglacial Highlands (ESH) have mapped and dated englacial ice sheet layers, hereafter referred to as ‘Internal Reflection Horizons’ (IRHs). The geometry and internal structure of IRHs can reveal the cumulative effects of surface mass balance, strain, basal melt and ice dynamics, to improve understanding of the glacial history of West Antarctic Ice Sheet (WAIS). Despite the airborne-surveyed IRHs however, international efforts to develop a continental-wide scale coverage of IRHs (i.e. AntArchitecture), are limited by a lack of data in the critical regions between the upper reach of Pine Island Glacier (PIG), Rutford Ice Stream (RIS) and Institute Ice Stream (IIS). This region is important because any significant collapse of WAIS or reorganisation of ice flow would likely be felt in the ESH because it hosts deep subglacial troughs (Ellsworth Trough and CECs Trough), that represent a potential connection between the Weddell and Amundsen Seas. Using an extensive ground-based ice radar dataset acquired by Centro de Estudios Científicos (CECs) we bridge this regional gap by mapping IRHs across the Amundsen-Weddell divide of the WAIS. This work links airborne-derived IRH datasets across PIG and IIS, to develop an extensive layer characterisation across a large area of West Antarctica. We present the regional internal structure of the ice sheet, gridded paleo ice surfaces, and identify areas with complex IRH structures, and evaluate the possible glaciological processes responsible. We then compare our results with modelled outputs of ice sheet geometry and outline our current understanding of the past ice flow behaviour of the ESH, and the implications for WAIS glacial history. We consider our results in the context of the characterisation of ‘old-ice’ in WAIS and in relation to the upcoming plans for accessing subglacial Lake CECs in order to determine its history. Powered by TCPDF (www.tcpdf.org).