Bulletin

This report is about the first Cretaceous symposium of South America. The main topics include the geological characteristics of different countries in America as such Brazil, Cuba, Chile, Argentina, Paraguay, Colombia, Uruguay in relation to different stages of the Cretaceous period. Brazil has a Proterozoic sedimentary area Including, paleozoic, cretaceous and tertiary basins, But the cretaceous rock are of vital Importance to the petroleum geology of Brazil. It also describes the chemical stratigraphy of the sandstones and the depositional architecture of the Bau ru group and paleocurrent paleoecological and paleobiogeographic Implications. Also most of the bio constructions formation are in Cuba Cretaceous sediments. In Chile Atacama region are important the mineral para genesis on the bitumen rich lavas metallotect, lower cretaceous. In Uruguay there is the conchostracans faunas from Castellanos formation in Santa Lucia basin lithologies and mineralizations in Valle Chico formation. In Chubut Province Argentina there are a calci c zeolites in upper cretaceous volcanic rocks.