EVOLUÇÃO PALEOGEOGRÁFICA E ESTRUTURAL DA PORÇÃO CENTRAL DA BACIA BAMBUÍ, NO NORTE DO ESTADO DE MINAS GERAIS

Resumo

Three large and distinct lithological sets were deposited at the center of the Bambuí Basin, during the final phase of the Pre-Cambrian period, respectively characterized by exclusive carbonated (limestones and dolostones), clastic and pelitic (siltstones and mudstones) and clastic or carbonated (siltstones and black limestones) natures. In previous works, such facies have been considered as in ill-defined lateral equivalence, strictly over the region which is now occupied by São Francisco River, under its thick alluvial deposits which masks all the details of contact. The present work establishes a characterization of the paleogeographical domains for each of the litho-stratigraphic units, which negates the suggested distribution of the facies by evidencing the complex relations exibited by them. In addition, the stratigraphic columns, proposed for the Paraopeba Formation, in the same region, cannot survive within the present model.