Cenozoic glacial history of northern Victoria Land (Antarctica): geomorphologic evidences and surface exposure ages.

• Main Authors: BARONI, CARLO, SALVATORE, MARIA CRISTINA, DI NICOLA L., STRASKY S., SCHLÜCHTER C., AKÇAR N., KUBIK P. W., WIELER R.
• Other Authors: Baroni, Carlo, DI NICOLA, L., Strasky, S., Salvatore, MARIA CRISTINA, Schlüchter, C., Akçar, N., Kubik, P. W., Wieler, R.
• Format: Conference Object
• Language: English
• Published: Australian and New Zealand Geomorphology Group and International Association of Geomorphologists 2009
• Subjects: Geomorphology; Glacial geology; Surface Exposure Dating; multiple cosmogenic nuclide; paleoclimatic evolution; East Antarctic Ice Sheet; Antarctic; Victoria Land; Antarc*; Antarctica; Ice Sheet
• Online Access: http://hdl.handle.net/11568/135648; http://trove.nla.gov.au/version/38753305

Antarctica has played an integral role in the global climate system since the Early Oligocene. It comprises a complex system of glacial bodies, each characterized by its own history, dynamics, reaction capability and time-response to environmental and climatic stresses. Our study focuses on northern Victoria Land (NVL), where an articulated glacial system behaves with its own dynamics, independently from the East Antarctic Ice Sheet (EAIS). A regional landscape analysis, based on glacial geologic and geomorphologic surveys and mapping, was conducted to investigate NVL glacial history in order to assess the relationship between EAIS and NVL glacial system. Through detailed field traverses in NVL, we identified and classified several geomorphologic units and glacial drifts offering valuable archives of past environmental changes and glacial advances. The polar environment endured in NVL since at least 7.5 – 8 Ma (and even before when considering the EAIS region). In such a highly conservative setting, surface exposure dating (SED) has proven to be highly valuable in order to establish a precise chronology of the landscape features. Through field observations in ice- free areas at the borders of outlet, valley and local glaciers, as well as in nunataks at the margin of the EAIS are combined with cosmogenic data from erosional surfaces and erratic boulders. Our data indicate several ice fluctuations, providing valuable insights into the paleoclimatic evolution of the study area. The employment of multiple cosmogenic nuclides (10Be, 26Al, 21Ne) constrains denudation rates which testify persistent climate stability with cold and dry condition. Complex glacial dynamics are unraveled in the coastal area as well as at the internal margin of EAIS. Our results provide valuable insights into the paleoclimatic evolution of the investigated area, allowing the reconstruction of the major global events recorded in NVL and the identification of significant relationships with other Antarctic regions.