Geomorphology and glacial-stratigraphy of James Ross Island, northern Antarctic Peninsula

STRELIN, J.; HEREDIA BARION, P.; CALABOZO, F.; VACA, M.; BARRIONUEVO, M.

Los Cocos, Córdoba

Workshop; IMCOAST Workshop; 2010

German Science Foundation (DFG)-Universidad Nacional de Córdoba

James Ross Island is located on the rain shadow of the northeastern tip of Antarctic Peninsula. The present island's landscape consists mainly of an up to 300 m thick ice cap and related outlet glaciers covering a stacked volcanic tablemountain/tuyas complex. Nevertheless the NW side of the island has a large ice free area where former glaciogenic landforms, shaped on Neogene volcanic and underlying Cretaceous marine sedimentary rocks, are significantly reworked by present mass wasting, periglacial (including glacio-nival), fluvial, and marine processes. The coast line is mostly deglaciated and characterized by abrupt, erosive shorelines, with active and fossil sea-cliffs and low depositional shorelines, with dominance of marine action (beach and spits) or fluvio-marine action (deltas and tidal flats). In this coastal area previous, Holocene and Upper Pleistocene glacial and marine activities are revealed by the morphology and stratigraphy of well preserved moraines and marine-terraces onshore. Moreover, outcrops of glacial, marine, and volcanic deposits, allows a fragmentary reconstruction of the glacier history of James Ross Island going back to the Upper Miocene. King George Island (South Shetland Islands Archipelago) located on the windward rainy side of the NW Antarctic Peninsula, offer a good opportunity to compare both morpho-structural and morphogenetic environments dominated by different tectonic and climatic regimes.