Hidroestratigrafia do Grupo Bauru (K) no Estado de São Paulo

Abstract

Geophysical logs, ditch samples and cores of water wells drilled in São Paulo State, Brazil, allowed the identification and correlation of different hydrostratigraphics units and the evaluation of hydraulic potential of the Bauru Aquifer System (Mesozoic of Paraná Basin). Identified units were Caiuá, Santo Anastácio, Birigüi, Adamantina and Marília aquifers, and Pirapozinho and Araçatuba aquitards. The aquifer units were differentiated in terms of isoliths of relative apparent permeability, as very permeable and moderately permeable. The isolith maps contemplate directly the most favorable potential areas to water production. The isoliths of high apparent permeability sandstone of Caiuá and Santo Anastácio aquifers showed larger concentrated values in the southwest occurrence area of the Bauru Group. The areas with best hydraulic potential for Birigüi Aquifer are concentrated on elongated strip along the center of his occurrence area. Adamantina Aquifer showed moderate and high isoliths of apparent permeability distributed in parallel strips to south and north of Tietê River. Resistivity logs of Marília Aquifer contemplate mainly the intense carbonatic cementation of the lithologies, hindering the distinction between high and moderate apparent permeability of its sandstones. The static water storage of the Bauru Aquifer System is about 1.600 km³, distributed by the Caiuá (150 km³), Santo Anastácio (560 km³), Birigüi (15 km³), Adamantina (810 km³) and Marília (80 km³) aquifers.