Evidence of brines interconnections and different flow patterns within the boulder clay glacier and its moraine (Victoria Land, East Antarctica).

Multi-technique integrated surveys were carried out to investigate brine characteristics, connectivity and flow patterns in the Boulder Clay Glacier area, Victoria Land, East Antarctica. Specifically, electromagnetic geophysical surveys focused mainly on Ground Penetrating Radar (GPR) and integrated by Frequency Domain induction, not only demonstrated the presence of brines in the subsurface, but also allowed to image several structures and glaciological elements. Chemical analyses suggested the origin and differentiation of the brines, providing evidence for interconnected pathways. To the best of our knowledge, this is the first time that brines interconnection and their chemical common footprint is demonstrated below a glacier and its moraine at shallow depth, combining boreholes, geophysical, geomorphological, and chemical data. This demonstrates that liquid flows can occur at very shallow depths, even in continental Antarctica, and that pressurised brines can flow beneath and through glaciers and moraines.