Notas petrográficas sobre a Série Ribeira, do Sul do Estado de São Paulo

Resumo

The author proposes that the tilted and epimetamorphic rocks occurring in the upper Riebira River, composed mainly of argillaceous sediments, should be detached from the top of the Sao Roque series, under the name of Ribeira series. In an isoclinal fold of this series near Iporanga, he discovered, in 1932, a 50-meter bed of a polygenic conglomerate whit sericitic cement, that he found to be a tillite. This formation was called Iporanga. In the following year, the writer and Dr. T. Knecht observed the great extent of the conglomerates, which were seen from the Pilões River up to the Pardo River, in the limits of the Sao Paulo and Paraná States. In 1938, the geologists T Knecht and J. Felicissimo Jor. described the same conglomerates at Pariquera-Assú, in the Lower Ribeira. The Ribeira series joins phyllites, slates, graphitic sandstones, arkoses and tillites, and has been traversed by, quartz veins, and dikes of grorudite and basic rocks. The author suggests the correlation of the Ribeira series (São Paulo and Paraná) with the Itajai (Santa Catarina). Lavras (Minas Gerais e Baia) and Corumbá (Mato Grosso) series, supposed to be Upper Algonkian or more likely Eocambrian. In all these series arkoses and tillites have been found, proving the existence of an inlandsis in South America at teh Early Paleozoic time