Glacial geomorphology of the tableland east of the Andes between the Coyle and Gallegos river valleys, Patagonia, Argentina

Abstract

We report the results of geomorphological mapping of the high tablelands of Patagonia east of the Andes and between the Coyle and Gallegos river valleys. The map covers a low-relief area of about 3400 km2 at a scale of 1:85,000. It contributes to knowledge of a landscape shaped by lobes of the Patagonian ice sheet and can be used as a tool for further Quaternary studies. The map was built from remote-sensing data, compiled, and analyzed in geographical information system packages and supported by fieldwork. It features glacial landforms including moraine ridges and belts, ground moraine, outwash plains, outwash fans, meltwater channels, traces of glacial lakes, and erratic boulders. Fluvial, aeolian, and volcanic landforms and structural features were also mapped to provide a complete understanding of the landscape. We define three glacial units that record the frontal positions of former piedmont glaciers. The criteria used to define these units are the morphology, maximum relief, boulder content of moraine ridges, and crosscutting relations.