Date of Award
Master of Science (MS)
College of Science and Mathematics
Earth and Environmental Studies
Thesis Sponsor/Dissertation Chair/Project Chair
The West Antarctic Ice Sheet is a major contributor to global sea level rise, yet its origin and dynamics are poorly known. The geochemistry of 35 diamictite samples from the CRP-1 and CPR-2A cores recovered by the Cape Roberts Drilling Project in the Ross Sea, Antarctica is evaluated to understand glacial sedimentation and flow paths during the Oligocene and Miocene, a period of warmer than present climate in the past. The major hypothesis to be tested is if the early Miocene ice sheet advance was the first major West Antarctic ice advance in the Ross Sea. The provenance of older Oligocene diamictites, present below this early Miocene stratigraphic level, will be analyzed to trace glacially transported sediment to a West Antarctic or an East Antarctic source. The project implies that if the Oligocene diamictites show a West Antarctica signature, a major ice sheet advance took place before the early Miocene, as proposed in previous geophysical research.
Whole rock analysis of diamictite samples is performed on an Inductively Coupled Plasma Mass Spectrometer (ICP-MS). This kind of analysis allows the interpretation of a range of elemental ratios that indicate specific sources to determine the sediment provenance for each diamictite sample. In addition, grain-size distributions (Martin and Passchier, 2010) will be used to assess the depositional setting of the diamictites. Results show a main East Antarctic provenance with a contribution from a West Antarctic source, suggesting the presence of a West Antarctic Ice Sheet advance during the Oligocene. These results enhance our understanding of ice sheet evolution and dynamics in Antarctica through warmer periods in the past and lead to better projections for global warming and rising sea levels worldwide.
Flores Garza, Celina, "Trace and rare earth elements analysis of Oligocene and Miocene diamictites in the Cape Roberts Project, Ross Sea, Antarctica" (2024). Theses, Dissertations and Culminating Projects. 1368.