Levantamentos magnetotelúricos na Bacia de Cuyo, Argentina

Abstract

The Cuyo basin have a lot of oil fields in production, and is located in the Mendoza region, in the Nothwest of Argentina. In that place, there is the subduction of Nazca plate under the South American plate, which presents differents dip angels (10º a 30º) on the North to South profile. Therefore, there is in this region differents kinds of vulcanic rocks, at west of the basin and, of course, there is a front of andean orogen that, some researches say to be afirmative, recover part of tertary beded sediments of the Cuyo basin west edge. Unfortunatelly, there is no croup out rocks in that place, which could prove this theory, and only geophysical could help to answer this question. The petroleum industry, of course, carried out a lot of reflexion seismic survyes on the west edge of the Cuyo Basin, at which weren't observed reflexions horizons, what was interpreted like velocity invertion. Then, the eletromagnetic methods are the only one that could have good application on the site and, for this prupose, were carried out two magnetotelurics profiles on the edge of the west Cuyo Basin, one in the West to East alignement, at latitud of Jocolí, called line I, and another to the North of basin, with East to West alignement, at latitud of Ramblón, called line 2. Both of the profiles were carried out with six magnetoteluric soundings, and with the results, two 2D invertions were interpreted, which are commented in the chapter six.