COG3

Title: Sedimentary provenance approaches to unraveling East Antarctica's ice sheet history

Abstract:
The study of glacially-derived material recovered from marine sediments located off the margin of East Antarctica provides a means for characterizing the sub-glacial geology obscured by the ice cover that spans more than 98% of the continent. These insights in turn provide characterization of sedimentary source areas, the knowledge of which can be applied to sediment provenance studies of ice rafted detritus (IRD), which in turn can used to study East Antarctic ice sheet history. This talk will focus on contributions to our understanding of the Mid-Miocene Climate Transition (MMCT), a period of global climatic shift that had a profound effect on many components of the Earth system, including terrestrial biota, ocean circulation, both ocean and terrestrial temperatures, sea-level, and ice volume. Despite inferences on the total amount of ice growth on Antarctica as a whole, little is known of the temporal and spatial evolution of the East Antarctic ice sheet at this time. Here we apply isotopic provenance studies (40Ar/39Ar hornblende ages and K/Ar and neodymium isotope measurements on the terrigenous <63 µm sediment fraction) in order to determine the source of glacially derived sediments deposited ca. 14.7 to 12.6 Ma off the coast of East Antarctica at IODP Site U1356.