Geological investigations of the fault lines in the rocks of the Transantarctic Mountains in the area of the Wilson Piedmont Glacier to understand uplift of the mountain range

Inferred fault lines in the rocks of the Transantarctic Mountains in the area of the Wilson Piedmont Glacier were investigated to add to the understanding of the uplift of the mountain range. Specifically, the Precambrian to Holocene geology of the Wilson Piedmont Glacier area was surveyed to i) define the eastern limits and geometry of the marker horizons which could serve to identify faults, including the Kukri Erosion surface, Beacon Supergroup and Ferrar Dolerite sills, ii) establish the field extent and nature of macro- and mesoscopic structures along the east side of the Transantarctic Mountains as a test of previously proposed uplift histories, and iii) determine if previously characterised Paleozoic granitoids suites of the Dry Valleys extend east to the Ross Sea, or if different granitoid rocks are present. The rocks investigated include pre-500 million year Koettlitz Group marbles and sandstones, 400-500 Ma granites and other crystalline rocks, 180-400 Ma Beacon Supergroup Sandstones, 170-180 Ma injected flat sheets of Ferrar Dolerite basalt, and <5Ma glacial deposits and a new outcrop of McMurdo Volcanics. Data were recorded in notebooks, and geological contacts and sample points were recorded on published USGS 1:50,000 topographic maps. Mapping was supplemented by aerial photo interpretation undertaken immediately prior to the field work. Hand samples of representative rock types for further laboratory analysis were bagged for transport back to New Zealand. Field notebooks, maps and photographs are held by the Institute of Geological and Nuclear Science, Dunedin.