SOBRE OS PALEOAMBIENTES DEPOSICIONAIS DO GRUPO PASSA DOIS

Abstract

This paper deals mainly with a critical revision of the paleoenvironments of sedimentation of the Brazilian Paraná Basin Permo-Carboniferous known as Passa Dois Group. This revision is based on new paleontological discoveries as well as sedimentary structure evaluation and available geochemical data. The author calls attention on the risks of inferences based on scarce data; however, he judges as reasonable the interpretation of paralic conditions for the sedimentary environments for the Irati Formation considering similar conditions for the sedimentary environment of Corumbatai (States of S. Paulo and Estrada Nova (State of Paraná), Santa Catarina and Rio Grande do Sul) formations. It is discussed here as well the problem of stratigraphical delimitations of this group and its subdivisions.