Proterozoic first-order sedimentary sequences of the Sao Francisco craton, eastern Brazil

The Sao Francisco craton in eastern Brazil hosts sedimentary sequences deposited between the Paleo-archean (similar to 3300 Ma) and Late Neoproterozoic (similar to 580 Ma). Proterozoic successions occurring in this region comprise five 1st-order sedimentary sequences, which besides episodes of global significance record major basin-forming events. The ca. 8000 m-thick Minas-ltacolomi 1st-order sequence, exposed in the Brazilian mining district of the Quadrilatero Ferrifero and containing as marker bed the Lake Superior-type Caue Banded Iron Formation, tracks the operation of a Wilson cycle in the Paleoproterozoic Era. The quartz-arenite dominated Espinhaco I and II sequences record at least two major rift-sag basin-forming events, which affected the host continent of the Sao Francisco craton at around 1.75 Ga and 1.57 Ga. The Macaubas sequence and its correlatives in the extracratonic domains witness the individualization of a Sao Francisco-Congo plate in synchronicity with the break-up of Rodinia in the Cryogenian period. The Sao Francisco-Congo plate together with various fragments derived from Rodinia re-assembled to form Gondwana in the Ediacaran period. In the course of the Gondwana amalgamation, orogenic belts developed along the margins of the craton; its interior, converted into foreland basins, received the shallow water carbonates and pelites of the Bambui 1st-order sequence and its correlatives. (C) 2011 Elsevier Ltd. All rights reserved.