Sao Francisco Craton

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Approximate location of Mesoproterozoic (older than 1.3 Ga) cratons in South America and Africa. The São Luís and the Luis Alves cratonic fragments (Brazil) are shown, but the Arequipa–Antofalla Craton and some minor African cratons are not. Other versions describe the Guiana Shield separated from the Amazonian Shield by a depression, and the Saharan Metacraton as a part of this West African Craton.

The São Francisco Craton is located in the eastern part of South America. Outcrops in the Brazilian states of Minas Gerais and Bahia.

It includes a number of different blocks of the Archean basement, separated by orogenic belts. The belts are characterized by sediment basins and passive continental margin, crossed by granite intrusions. The Paleoproterozoic (about 2.5 to 2.0 Ga) was the source of orogenetic belts and the current configuration of the craton. The São Francisco Craton around 1.0 Ga ago was located in the South of the supercontinent Rodinia and after the fragmentation of Rodinia in the late Proterozoic (700 Ma) became a member of the supercontinent Gondwana until its fragmentation in the Jurassic (about 180 Ma): the opening of the Atlantic Ocean left South Africa in the Congo craton and the São Francisco in South America.

The ancient Paleoproterozoic orogenic belts of the São Francisco Craton contain many minerals, particularly iron and gold, and are a major source of income for the mining industry in Brazil.


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