Evolution of the East Antarctic Ice Sheet Since Glacial Inception From Seismic Stratigraphic Records in Vincennes Bay

Abstract Seismic reflection data from Vincennes Bay, East Antarctica, provide the first insights into the Cenozoic evolution of the East Antarctic Ice Sheet (EAIS) in the Knox Coast. Long‐distance seismic horizon correlation allows age estimates for the seismic stratigraphic framework constructed for the continental shelf. Preglacial depositional patterns reveal extensive fluvial plains on the continental shelf from the Late Cretaceous until the latest Eocene (∼34 Ma). These transitioned to glaciofluvial outwash plains during the late Oligocene. The earliest clear indication of ice sheets present on the Vincennes Bay continental shelf are two generations of large buried tunnel valley systems that developed during the Oligocene‐Miocene Transition (∼24 Ma) and early Miocene during meltwater‐rich glaciations originating in the Knox Coastal Plain. Glacially transported sediment wedges deposited at the end of the early mid‐Miocene (>∼14 Ma) mark the beginning of steep glacial progradation of the continental shelf continuing through the Miocene and Pliocene. Ice sheet development from the late mid‐Miocene to the Quaternary is likely driven by the Aurora Subglacial Basin via the Vanderford Glacier. This suggests a major reorganization of ice flow from the early glaciations of the Oligocene and early Miocene to the later development of modern configurations, established in the late mid‐Miocene. Our results provide the first data of the Cenozoic development of the EAIS in Vincennes Bay and demonstrate the variability of ice flow conditions with past climatic changes.