Sabrina Ortlepp

Late Quaternary Environmental History of Taylor Valley,: Southern Victorialand, Antarctica, Reconstructed by a Multidisciplinary Study of Lake Sediments Sabrina Ortlepp

In the unglaciated areas of Antarctica, lake sediments act as archives of the regional environmental and climatic history. In most cases, the records are restricted to the Holocene. Amongst the few exceptions are lakes in the McMurdo Dry Valleys, southern Victoria Land, which are known to have remained mostly ice-free during the Last Glacial Maximum. Within the scope of an U. S.-American-German expedition in austral summer 2002/2003, several sediment cores were recovered from three major lakes in the Taylor Valley: lakes Fryxell, Hoare, and Bonney. In order to reconstruct the late Quaternary regional environmental and climate history, sedimentological, biogeochemical, mineralogical, and chronological investigations were conducted on the sediment sequences recovered from Lake Hoare (core Lz1020) and East Lake Bonney (core Lz1023) within the scope of this thesis. This study shows that the investigated lake sediment records provide crucial information about the late Quaternary environmental history of Taylor Valley, but should be interpreted in context with ice core records, terrestrial, and marine archives for a better understanding of the regional paleoenvironment, and paleoclimate.