ANÁLISIS PETROGRÁFICO PRELIMINAR SOBRE LAS ARENISCAS DE LA FORMACIÓN SANTA CRUZ (MIOCENO MEDIO) EN EL FLANCO NORTE DE LA CUENCA DEL GOLFO SAN JORGE

OLAZÁBAL, S.X; MAISA TUNIK; JOSÉ M. PAREDES; MAURO N. VALLE

San Miguel de Tucumán

Congreso; XX Congreso Geológico Argentino; 2017

The petrography of the aeolian and fluvial deposits of the Santa Cruz Formation on the northern flank of the Golfo San Jorge is presented in this study. The rocks were classified as litharenites and feldspathiclitharenites .Lithic fragments derived from basic, intermediate and acidic rocks were recognized. Paleovolcanic, neovolcanic, plutonic and metamorphic rocks were differentiated using their diagnostic textures. The cements identified are rim type clay ceolithic and carbonatic, while the porosity is intergranular and by dissolution in feldespar grains, sustaining a shallow eodiagenesis. Petrographic results complemented with paleocurrent measurements and regional geological data define possible provenance areas for the Santa Cruz Formation which are located 200 km northwest from the study area.