Potential fields as a tool to characterize the inaccessible areas of the earth: The case of Pine Island–Ellsworth Mountains area, West Antarctica

Abstract

We seek to characterize the geophysical properties of the West Antarctic Rift System. While it is recognized as one of the largest rift systems on the earth, the West Antarctic Rift System is poorly understood as it is covered by the thick West Antarctic Ice Sheet, making any geologic evaluation difficult. We used the potential-field data sets acquired by the British Antarctic Survey, which included aeromagnetic surveys, to conduct a multiscale analysis to identify the main structural lineaments, i.e., contacts, dikes, sills, volcanic necks and conduits, and spherical source distributions. Several interesting areas were defined in which contact-type sources were associated with faults bordering major rift systems (Pine Island, Byrd Subglacial Basin, and Bentley Subglacial Trench) or related to the tributaries in the Pine Island Rift. Moreover, we detected magmatic sources close to rifting zones based on their shape and orientation (Bentley Subglacial Basin edges), helping to define the depth of the sub-ice topography. Our results helped improve our knowledge of the structural regional geology of the West Antarctic Rift System. This work opens interesting scenarios about the extent and position of magmatic sources and how they contribute to the topography of this sector of the West Antarctic Rift System.