| Summary: | The present research represents an integrated magnetostratigraphic and environmental magnetic study of Cenozoic sediments from selected circum-Antarctic drill cores. The studied cores were selected to obtain a more complete picture of glacial history that can only be obtained by linking ice-proximal records from the continental shelf to the deep-sea record through key drill sites from the Antarctic margin and other coeval sequences from the Southern Ocean. These locations include: (1) a Cape Roberts Project drill-hole from the Ross Sea, other sedimentary sequences from the Southern Ocean drilled in association with the Ocean Drilling Program (ODP), including (2) holes 689B, 689D, 690B and 690C (ODP Leg 113) from Maud Rise, Weddell Sea, and (3) a transect of two sites drilled during ODP Leg 188 across the Prydz Bay continental shelf (Site 1166) and rise (Site 1165) in the Indian Ocean sector of the Antarctic margin. The results presented in this thesis provide an improved view of the timing and extent of events associated with the onset and subsequent history of Antarctic glaciation. In addition to these findings, they provide further evidence for an external forcing mechanism driving the dynamics of the early Oligocene East Antarctic Ice Sheet during its initial development. Finally, beside these results, paleomagnetic results from ODP Site 1165 (Prydz Bay, Antarctica), ODP Site 883 (North Pacific Ocean), ODP Site 1124 (Southwest Pacific Ocean) and ODP Site 998 (Caribbean Sea), provide evidence that dissolution of magnetite is a common feature in sediments with elevated porewater silica concentrations (e.g. in the Southern Ocean). This observation has important implications for paleomagnetic investigations of siliceous sedimentary environments.
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