Late Quaternary Climatic and Environmental History of the Amery Oasis, East Antarctica

In austral summer 2001/2002, a joint German-Australian field capaign took place in the Amery Oasis (East Antarctica) under the participation of scientists and technicians from Leipzig University and AWI Potsdam. The expedition was funded by the Antarctic Science and Advisory Committee (ASAC), the Alfred Wegener Institute for Polar and Marine Research (AWI) and the German Research Foundation (DFG). The project is based on earlier Russian-German expeditions to the Schirmacher and Untersee Oasis (1991/1992 and 1994/1995), the Bunger Oasis (1993/1994), and an Australian-German expedition to the Windmill Islands (1998/1999). It is an important contribution to the Australian-German research project "Palaeoenvironments of the Antarctic coast from 50°E to 120°E".

The overall goal of the research program is to understand palaeoenvironmental responses to global climate fluctuations along the margins of the Antarctic ice sheet, inferred from geomorphology (Australian partners) and lacustrine sediment records (University Leipzig, AWI Potsdam). The Amery Oasis represents one of the largest ice-free areas in Antarctica (1800 km²) and lies adjacent to the western side of the large glacial system of the Lambert Glacier and the Amery Ice Shelf, which drains about 9% of the Antarctic ice sheet. Environmental reconstructions will help to unravel glacial dynamics during the last glacial maximum and the postglacial Holocene environment of the study area. 

During the Amery Oasis expedition, lake sediment cores and water samples were recovered from two freshwater lakes (Radok Lake, Lake Terrasovojy) and from one epishelf lake (Beaver Lake). The sediment records will be analysed by sedimentological, geochemical, and micropalaeontological methods. Preliminary findings from Lake Terrasovoje reveal the onset of postglacial conditions some 12500 years ago, documented by an unique 2.70 m thick succession of laminated organic rich muds. The deposits represent one of the oldest and most complete Holocene lacustrine records in East Antarctica and promise insights into postglacial climate development at high temporal resolution. The laminae of the sediment record consist of alternating layers of organic-rich mud and detrital clays. Element Scanner data of Fe are a useful tool to detect the detrital layers. 

Outcomes

• Hultzsch, N. (2006). Lakustrine Sedimente als Archive des spätquartären Umweltwandels in der Amery-Oase, Ostantarktis. PhD Thesis, University Potsdam/AWI.

• Hultzsch, N., Wagner, B., Diekmann, B., White, D. (2008). Mineralogical Implications for the Late Pleistocene glaciation in Amery Oasis, East Antarctica, from a lake sediment core. Antarctic Science, 20/2: 169-172.