Push moraines in the upper valley of Santa Cruz river, southwest Argentina. Structural analysis and relationship with Late Pleistocene paleoclimate

• Main Authors: Goyanes, G., Massabie, A.
• Format: Journal/Newspaper
• Language: unknown
• Subjects: Argentina; Glacial landforms; Last Glaciation; Push moraines; Santa Cruz river; Southern Patagonia; drumlin; glacial landform; glaciotectonics; ice sheet; overturn; Pleistocene; push moraine; thrust; Patagonia; Santa Cruz River [Santa Cruz]; Santa Cruz [Argentina]; Ice Sheet
• Online Access: https://hdl.handle.net/20.500.12110/paper_08959811_v57_n_p1_Goyanes

The upper cliff of the Santa Cruz River was used to assess the proglacial environments of the Argentino Glacier outlet of Late Pleistocene age. These cliffs show glaciolacustrine, fluvioglacial and till deposits, where only the first one are deformed. Glacial landforms in the area and these structures suggest that the ice mass advanced, topographically controlled, towards the east from the Patagonian Ice Sheet pushing up the proglacial sediments.The spatial arrangement of thrusts and overturned folds, the drumlins-flutes moraine directions and the end moraines shape, allow inferring the dynamic and the Argentino glacier profile. Detailed analyses of the glaciotectonic structures indicate that these have two origins: load in the north with stress transfer to the southeast, and push from the west. Through the analysis of deformed sediments, their thickness and their sedimentary and structural features, three zones of deformations were recognized. Each of these zones was associated to glacial advances because of changes of the regional climate conditions. © 2014 Elsevier Ltd. Fil:Goyanes, G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Massabie, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.