experience of using low- and medium-frequency ground penetrating radars to study the internal structure of a glacier and the bedrock topography in the schirmacher oasis area, east antarctica

During the expeditionary research of 2023-2024 in the conditions of thick antarctic ice sheet, the medium- and low-frequency ground penetrating radars (gpr) oko-3 with a 150 mhz antenna and triton-m with an extendable 25-50-100 mhz antenna (logis llc, russia) improved and adapted for glacier investigations were tested for the first time. an example of the ice sheet study in the schirmacher oasis area showed that the oko-3 gpr allows obtaining detailed information on the internal structure of the ice sheet to depths of about 200 m and successfully solving glacial stratigraphy issues. the triton-m gpr has proven itself well for mapping the roof of underlying rocks to depths of 250-300 m. the article presents new data on the glacier structure in the novo runway area, as well as information on the glacier thickness and the subglacial rock base topography near the schirmacher oasis (novolazarevskaya and maitri stations). typical structures of the glacier strata in this area are gently sloping layers and steep folds that replace them, complicated by crevasses. the subglacial topography to the south of the oasis is quite gentle. individual uplifts and depressions do not exceed 30 m. the interface between the ice and the rock base was recorded over a distance of 4.5 km to the south of the oasis. in the east, about a kilometre from the last rock outcrop, the oasis is limited by a sharp depression in the bed. new data opens up the possibility of constructing the ice sheet models, studying its dynamics and evolution, and finding patterns in the crevasse formation.