The late Quaternary environmental- and climate history of the Rauer Group, East Antarctica

The late Quaternary climate history of East Antarctica is subject of intense research. Aim is to ascertain the role of the Antarctic region in global climate change. Current reconstructions of climate- and environmental conditions in East Antarctica from different archives (e.g. ice cores and marine sediments) often show equivocal results and there is evidence for considerable differences on regional scale. Due to the ice cover of the continent geological archives on land are rare and only crop out in small areas at the margin of East Antarctica. This so called oasis yield important information, since they usually contain numerous lakes and marine basins filled with sediments, that allow inferences about the timing of ice sheet retreat and climate- and environmental developments since. Within the scope of an RV Polarstern expedition in February/March 2007 a three weeks field campaign was carried out to sample lakes and marine basins and to conduct geomorphological studies.

Current results

The Rauer Group is an archipelago of about 400 small islands in the Prydz Bay region close to the East Antarctic ice sheet. The islands are ice free an cover an area of about 300 km². During the last major advance of the East Antarctic ice sheet in the late Pleistocene the whole islands were covered by ice. One aim of this study is to date the retreat of the ice sheet from the islands. Furthermore a relative sea-level history is to be established by geomorphological features like raised beaches.

Today the surface of the islands is bare rock and exhibits extensive weathering. The dry climate and high wind speeds cause aeolian transport to be an important process of sediment movement. Despite the extreme conditions some small lakes and ponds exist on several islands. They are fed by melt water from snow patches in the catchment area. The marine basins and inlets between the islands are covered with sea ice in winter that partly breaks up in the summer months. Marine sediment cores contain a complete record over the past 11.000 years. They allow detailed information about environmental changes like duration of ice cover and biological activity.

Perspectives

Sedimentological and geochemical studies on marine sediment sequences show short term fluctuations as well as long term trends influencing sedimentation in this basins. For final conclusions a comparison to the results from other oases is necessary.

Scientists

Prof. Dr. Martin Melles
Institut for Geology and Mineralogy
University of Cologne

Dr. Bernd Wagner
Institut for Geology and Mineralogy
University of Cologne

Dipl.-Geol. Sonja Berg
Institut for Geology and Mineralogy
University of Cologne

In cooperation with
Holger Cremer, Department of Paleoecology, Utrecht University, The Netherlands
Duanne White, Department of Physical Geography, Marquarie University, NSW Australia

Research areas

Rauer Islands, Antarctica

Publications

Verleyen E, Hodgson DA, Sabbe K, Cremer H, Emslie SD, Gibson J, Hall B, Imura S, Kudoh S, Marshall GJ, McMinn A, Melles M, Newman L, Roberts D, Roberts SJ, Singh SM, Sterken M, Tavernier I, Verkulich S, Van de Vyver E, Van Nieuwenhuyze W, Wagner B, Vyverman W, 2011. Post-glacial regional climate variability along the East Antarctic coastal margin – evidence from shallow marine and coastal terrestrial records. Earth Science Reviews 104: 199-212.

Wagner B, Ortlepp S, Doran PT, Kenig F, Melles M, Burkemper A, 2011. The Holocene environmental history of Lake Hoare, Taylor Valley, Antarctica, reconstructed from sediment cores. Antarctic Science 3, 307-319.

Berg S, Wagner B, Cremer H, Leng MJ, Melles M, (in press). Late Quaternary environmental and climate history of Rauer Group, East Antarctica. Palaeogeography, Palaeoclimatology, Palaeoecology DOI 10.1016/j.palaeo2010.08002

Berg S, Wagner B, White DA, Melles M, 2010. No significant ice-sheet expansion beyond present ice margins during the last 4500 yr at Rauer Group, East Antarctica. Quaternary Research, 74: 23-25.

Wagner B, Ortlepp S, Kenig F, Doran PT, Melles M, 2010. Palaeoenvironmental implications derived from a piston core from East Lake Bonney, Taylor Valley, Antarctica. Antarctic Science 22, 522-530.

Berg S, Wagner B, White DA, Cremer H, Bennike O, Melles M, 2009. Short Note: New marine core record of Late Pleistocene glaciation history, Rauer Group, East Antarctica. Antarctic Science, 31/3, 299-300.

White DA, Bennike O, Berg S, Harley SL, Fink D, Kiernan K, McConnell A, Wagner B, 2009. Geomorphology and glacial history of Rauer Group, East Antarctica. Quaternary Research 72, 80-90.

Homepage

Sonja Bergs Homepage

Research funding organisation

German Research Foundation

Project numbers ME1169/15, WA2109/2:
Funding period: 2007 - 2009