Geología y evolución tectónica del frente cordillerano a los 36º30´S: Bloques de Yihuín Huacay Puntilla de Huincán.

GALARZA, B; ZAMORA VALCARCE, G; FOLGUERA, A; BOTTESI, G

revista de la asociacion geologica argentina

Asociacion Geologica Argentina

Año: 2009 vol. 65 p. 170 - 191

0004-4822

The easternmost sector of the Malargüe fold and thrust belt, between 70° and 69°40’W, in southern Mendoza Province at the Puntilla de Huincán area, is characterized by the development of thick-skinned structures. Three main thrusts are defining the orogenic front, front. The westernmost thrust has a distinctive East-vergency in contraposition to the other two corresponding to backthrusts. Some secondary structures constitute thin-skinned thrusts, with decollements located at the Middle Cretaceous Huitrín Fm. These structures are modified at surface by the emplacement of Miocene Molle Fm. intrusives. Andean uplift at the orogenic front through these latitudes was mainly Upper Miocene in age, and was coetaneous to the emplacement of a volcanic arc between 19 and 17 Ma in the area, caused by the shallowing of the subducted plate at this time. However, the Puntilla de Huincán constitutes an older late Cretaceous structure associated with synorogenic sedimentation.