Landscape Evolution of Southern Patagonia

Abstract

Investigations have been focused on the glacial history and valley development in the region of the terminal basins Lago Argentino, Lago Viedma and the adjacent Río Santa Cruz and Río Shehuen Valleys, as well as on the stratigraphic classification and absolute chronology of Middle and Late Quaternary coastal deposits along the Atlantic coast of Patagonia from the Península Valdés in the north to the Bay of San Julián in the south. They indicate that characteristics of Late Miocene and Early Pliocene times were the deposition of the widespread Patagonian Gravel formation and the main epirogenic uplifting, as well as the fluvial incision down to ca. 110 m above the recent valley floors, and that the oldest Andean foreland glaciations exntended to the east as fas as the major Pleistocene ones. Along the Patagonian Atlantic coast, which is characterized by a slow uplift trend, coastal terraces of Middle and Late Quaternary age are preserved in different elevations, probably as results of eustatic sea-level oscillations.