Spectral evidence of paleozoic structure in the western Precordillera, San Juan (31º15'S), Argentina

ARIZA, J.P.; VUJOVICH, G.I.; BOEDO, F.L.; MARTÍNEZ, M.P.; PEREZ, S.B.; RAMOS, V.A.

Viña del Mar

Congreso; International Geological Congress on the Southern Hemisphere; 2013

Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS)

The western Precordillera (Baldis et al., 1982) is located in the western central region of Argentina (Fig. 1). Geologically, it is characterized by the development of an Andean thin- skinned fold and thrust belt (Cristallini and Ramos 2000), where the internal structure of each thrust sheet shows evidence of several overlapping deformational phases (von Gosen, 1992; 1995). The stratigraphy of the western Precordillera in the area (Fig. 1) is represented by slope and deep marine siliciclastic facies (Don Polo, Alcaparrosa, Calingasta and El Codo formations) (Quartino et al., 1971). These units are covered unconformably by both continental and marine neopaleozoic deposits (El Raton and El Salto formations, respectively). The stratigraphic succession culminates with volcanosedimentary triassic units (Barredo and Ramos, 2010), and cenozoic continental units. Based on different techniques of digital image processing (Sultan et al., 1986; 1987; Gad and Kusky, 2006) we have recognized the main structural features. The use of supervised classifications and mathematical operations among bands (5/7, 5/1, 5/4 * 3/4 and 7/5, 5/4, 3/1) show a robust structural framework of the study area.