Reconstruction of the late quaternary glacial geology on King George Island, South Shetland Islands: First steps of a geoscientific project

• Main Authors: Heredia Barion, P. A., Strelin, J., Astini, R., Kuhn, Gerhard
• Format: Conference Object
• Language: unknown
• Published: XIX Congreso Geológico Argentino 2014
• Subjects: Antarc*; Antarctic; Antarctic Peninsula; Antarctica; Bransfield Strait; Isla 25 de Mayo; King George Island; South Shetland Islands
• Online Access: https://epic.awi.de/id/eprint/40963/; https://epic.awi.de/id/eprint/40963/1/Certificado_II-2.pdf; https://hdl.handle.net/10013/epic.47935; https://hdl.handle.net/10013/epic.47935.d001

King George Island (Isla 25 de Mayo) is the largest one of the South Shetland Islands (SShI). This archipelago is located approximately 120 km NW of the Antarctic Peninsula, from which it is separated by the Bransfield Strait (Mar de la Flota). The SShI are located just south of the Antarctic Convergence Zone in a key location for investigating glacial and climatic fluctuations relative to both the Southern Hemisphere and the rest of Antarctica. The geomorphology and glacier geology of the SShI (Sugden and John 1973, Hall 2003 and 2007, Del Valle et al. 2007, Strelin 2010, Simms et al. 2011) constitutes a fragmentary record. Despite the deglaciation, inland ice free areas are scarce and are strongly affected by the thaw with the consequent destruction of previous geoforms. The few obtained radiocarbon ages on land exposures have poor stratigraphic control being necessary to consider the problems of pollution and the reservoir effect that affect them. Based on geochemical and sedimentological proxies and radiocarbon dating in sedimentary cores obtained from bays, some glaciers advances and warm periods have been inferred for the middle and late Holocene, among them are those corresponding to the Medieval Climate Optimum and the Little Ice Age (LIA) (Yoon et al. 2000 and 2004, Hass et al. 2010, Monien et al. 2011). It should be noted that for some glaciological reconstructions based on organic radiocarbon dating on marine sediments the ages are still questionable. Often it does not exist yet a clear criteria of correlation that allow to link between glaciterrestrial sediments and glacimarine ones. The study of the glacial, periglacial and coastal marine record of King George Island has a particular importance to enhance the knowledge of its paleoenvironmental evolution since the Marine Isotopic Stage 3 (MIS 3). There is no precision on the beginning and end of the Last Glacial Maximum (LGM), nor on the rhythm of the deglaciation post-LGM, known as Termination 1, both for coastal and marine areas, as well as ...