Petroleum Geology of Gondwana Rocks of Southern Brazil

Abstract

This paper is a condensed version of a study made for the Brazilian Government and published as Boletim 5, Rochas Gondwanicas e Geologia do Petroleo do Brasil Meridional, of the Servico de Fomento da Produccao Mineral of the Departamento Nacional da Produccao Mineral, Ministry of Agriculture. (Many well logs and analyses not given in the present paper may be found in the Portuguese bulletin.) It represents the results of a very extensive geological field study of Southern Brazil, and covers the states of Sao Paulo, Parana, Santa Catharina, and Rio Grande do Sul. The logs and locations of more than seventy borings drilled in this area were for the first time carefully analyzed and located on the accompanying map. The existing bibliography was duly considered, as well as the writer's previous studies and knowledge of the Gondwana rocks of several South American countries. The paper gives a new interpretation of the structural characteristics of the Parana Basin, and sets forth many new geological observations and facts, besides making a close correlation with the known Gondwana rocks of other continents. The stratigraphy of the Santa Catharina system of Southern Brazil has been slightly modified in accordance with the most recent data. The geological analysis of this part of Brazil, as correlated with systems of Gondwana rocks known in many other continents and countries, permits certain positive conclusions regarding the petroleum geology of Southern Brazil. The many geological cross sections of Southern Brazil and neighboring countries (drawn for the first time) clearly demonstrate the structural character of the basin and its relationship with any oil accumulations, if such exist. End_Page 1725------------------------------ Fig. 1. Paleogeographic sketch of probable extension of Gondwana continent in Southern Hemisphere and India at beginning of Permian age. Arrows indicate movements of ice sheets, and triangles remains of glaciations. End_Page 1726------------------------------