Geologia

Revista Brasileira de Geociências

27(3):269-282, setembro de 1997

ESTRATIGRAFIA E SEDIMENTAÇÃO DA BACIA SANFRANCISCANA: UMA REVISÃO
JOSÉ ELOI GUIMARÃES CAMPOS & MARCEL AUGUSTE DARDENNE
ABSTRACT

STRATIGRAPHY AND SEDIMENTATION OF THE SANFRANCISCANA BASIN: A REVIEW

This paper presents a stratigraphic and depositional systems review to the Phanerozoic cover of the São Francisco
Craton, defined as the Sanfranciscana Basin.

The Phanerozoic cover is composed mainly of sedimentary continental rocks and minor explosive volcanic rocks.
The stratigraphy and sedimentology of the Phanerozoic successions are summarized as follows:
Santa Fé Group (Carboniferous-Permian) -divided into Floresta and Tabuleiro formations. This glaciogenic sequence represents the gondwanan glaciation record in the Sanfranciscana Basin. These sediments are preserved in valleys excavated in the basement and crop out in most of the basin .
Areado Group (Early Cretaceous) -constituted by the Abaeté, Quiricó and Três Barras formations, characterized by lateral and vertical interfingerings. The Abaeté Formation was deposited by braided stream and the in southern area by alluvial fans; the Quiricó Formation records a lacustrine sedimentation. and the Três Barras Formation, was deposited in the fluvial, fluviodeltaic and aeolian environments. The Areado Group is thick in southern portion of the basin (200 meters); it is less than 60 meters and discontinous in the central-northern areas.
Mata da Corda Group (Late Cretaceous) -composed by the Patos and Capacete formations. The Patos Formation is composed by alkaline volcanic rocks. The Capacete Formation represents the distai epiclastic sediments with important aeolian sand contribution. It is present only in the southern sector of the basin.
Urucuia Group (Late Cretaceous) - composed of sandstones, divided into Posse (with Facies l e 2) and Serra das
Araras formations, respectively interpreted as dry field dune deposits, braided