ESTRATIGRAFIA DE SUBSUPERFÍCIE DO GRUPO BAURU (K) NO ESTADO DE SÃO PAULO

Abstract

SUBSURFACE STRATIGRAPHY OF BAURU GROUP (K) IN SÃO PAULO STATE, BTAZIL Subsurface studies using geophysical logs and well data obtained from water wells were very important in defining stratigraphic and hydrostratigraphic frameworks of the Mesozoic Bauru Group sedimentary units of Paraná Basin, in the State of São Paulo. In the present study two important regional unconformity surfaces were identified-S1 and S2-constituting excellent markers which can be correlated to formal lithostratigraphic units. S1 separates underlying Caiuá and Pirapozinho formations from overlying Santo Anastácio Formation. S2 surface is coincident with the contact between underlying Santo Anastácio Formation and overlying Araçatuba and Adamantina formations. New lithostratigraphic relationships for the Bauru Group were obtained applying correlation and interpretation criteria based upon regional unconformity surfaces. Caiuá, Santo Anastácio, Araçatuba, Adamantina and Marília formations were recognized in subsurface in addition to two new formations named Pirapozinho and Birigüi. Sedimentary evolution of Bauru Group is marked by three main depositional phases separated by erosive and non-depositional events of regional extension.