Detection of Paleofaults of Basement with gravity data in the portion of Argentina with Flat Slab in The Nazca Plate

GIMENEZ, MARIO E.; MARTINEZ, M. PATRICIA; INTROCASO, ANTONIO

Mendoza

Congreso; Gondwana-12. “Geological and Biological Heritage of Gondwana”; 2005

A Bouguer anomalies chart corresponding to a broad area in Argentina between 65º and 70º West Longitudes and 28º and 33.5º South Latitudes was dealt with Euler Deconvolution, Tilt and Tilt Gradient methods. For the Euler Deconvolution method a 30 km by 30 km square window was considered, taking into account the widths of the involved structures (Precordillera, Pampean Ranges of Pie de Palo, Valle Fértil, Velasco, Famatina System, San Luis Ranges, etc.). Different structural indexes (SI) were also tested, adopting 0.5 and 1 as optimal values since the results can be related to well known terranes sutures and at least five EW big faults lineaments. Results are confirmed by other two techniques: Tilt and Gradient Tilt, that show good agreement while overlapping lineaments previously obtained, mainly the NS sutures. These methods are better to identify NS than EW tendencies. Excellent results obtained encourage us to apply these accurate techniques to magnetic data.