MANIFESTACIONES GEOMORFOLÓGICAS Y GEOFÍSICAS DE UNA ESTRUCTURA GEOLÓGICA PROFUNDA AL SUR DE LA SIERRA DE PIE DE PALO

MARTINEZ, M PATRICIA; PERUCCA, LAURA; GIMENEZ, MARIO E; RUÍZ, FANCISCO

REVISTA DE LA ASOCIACIÓN GEOLÓGICA ARGENTINA

ASOCIACIÓN GEOLÓGICA ARGENTINA

Lugar: Buenos Aires; Año: 2008 vol. 63 p. 104 - 111

0004-4822

The results of the present study show a relation of geomorphologic and geophysics evidences with a structure found in the upper crust south of the Pampean Pie de Palo range, with which is similar in size. For this purpose, a chart of Bouguer anomalies was calculated from gravity values for the Pie de Palo range and surrounding areas. Besides, the Euler deconvolution method was applied, with window widths from 20 to 25 kilometers and structural indices of 0.5 and 1. The responses obtained with this method using both indices point to a concentration of solutions in correspondence with the following structural features found by geologic research: The Desaguadero-Bermejo megafault. The eastern boundary of the Precordillera Moreover, the existence of an important accumulation of trapezoidal shaped solutions was determined south of the Pie de Palo range. Their sources respond to depths from 10 to 20 km. The geomorphologic evidences found in this region seem to corroborate the existence of the formerly mentioned rising structure in the surface, as suggested by the successive migrations of the course of the to the north, and of the courses of the Mendoza and Tunuyán rivers to the south, which took place in prehistorical and historical time. This tectonic elevation can be compared to the one occurred in 1977 in the , during an important earthquake, when the Pie de Palo range rose 1.20 metres.