Morphotectonic Analysis in the Eastern Piedmont of the Sierra de La Huerta, Western Sierras Pampeanas, San Juan, Argentina

ROTHIS, LUIS MARTÍN; HARO, FEDERICO MIGUEL; PERUCCA, LAURA PATRICIA; SANTI MALNIS, PAULA; ALCACER, JUAN MANUEL; VARGAS, HORACIO NICOLAS

Advances in Geomorphology and Quaternary Studies in Argentina

Springer

Año: 2020; p. 114 - 128

Tectonic geomorphology is a useful discipline to investigate the effects of active tectonic processes upon landforms. The Andean back arc between 27° S and 33° S is characterized by intense seismicity, being the epicentre of the most damaging earthquakes in Argentina. Those events produced deformation, causing changes on the land surface morphology. A geomorphological and a morphotectonic analysis were carried out in the eastern flank of the Sierra de la Huerta to characterize the available evidence of tectonic activity. Three morphostructuralunits (named as Mountain, Transition and Depression) were recognized.The transition unit shows Quaternary active faulting where eight fault traces with a NW trend and associated scarps were identified. These evidences of Quaternary faulting were assigned to the Marayes Fault System. Detailed topographic profiles perpendicular to the strike of fault scarps allowed to measure main deformation to the north of the study area. Neotectonic deformation in the Arroyo Los Papagayos (arroyo = creek, sometimes an ephemeral one) produced anomalies in its pattern and longitudinal profile. Thus, this study allowed the consideration of the Marayes Fault System as a potential seismogenic source.