Glacial geomorphological characterization and glacigenic sedimentation in Admiralty Bay, Maritime Antarctica

Resumo

The study of the relationship between geomorphology and sedimentation processes is important as it clarifies information about relict landscapes. These processes are understood based on glacial landforms and the characteristics of their sediments. The objective of this article is to investigate glacial geomorphology and associate it with the attributes of glaciogenic sediments in the proglacial areas of the Baranowski, Windy, and Dobrowolski glaciers in Admiralty Bay, King George Island, and to infer changes in these glacial environments. Sediment samples were collected from depositional features during fieldworks (2019 and 2023), which underwent granulometric and morphoscopic analyses. The visual identification of glacial landforms followed criteria of morphology, morphometric characteristics, depositional environment, sedimentology and genesis. The sediments were interpreted as glaciogenic and related to moraine deposits. The geomorphological mapping identified glacial landforms that provide information on aspects such as the direction of glacial flow, area, and thermo-basal regime. The subaerial environment was observed to be related to the submarine environment through glaciers, mass movements and the sediment supply via meltwater. Thus, there is continuity in the processes related to the glacier: the closer to it, the more dynamic the environment, while as the distance increases, the terrain tends to present reworked or smoothed landforms.