
A sequência pré-glacial do Grupo Macaúbas na área-tipo e o registro da abertura do rifte Araçuaí
2008; Sociedade Brasileira de Geologia; Volume: 38; Issue: 4 Linguagem: Inglês
10.5327/rbg.v38i4.1434
ISSN2317-4889
AutoresMaximiliano Martins, Joachim Karfunkel, Carlos Maurício Noce, Marly Babinski, Antônio Carlos Pedrosa‐Soares, Alcídes N. Sial, Dunyi Liu,
Tópico(s)Geological formations and processes
ResumoThe Macaubas Group on the Macaubas river basin (MG) and the register of the rifting phase of the Aracuai Basin. This paper presents the sedimentary evolution and a new stratigraphy sug- gested by the rift phase of the Macaubas Group and Espinhaco Supergroup of the Aracuai orogen, located at the Macaubas River basin (Minas Gerais State). The Espinhaco Supergroup is formed by the Resplandecente Formation (aeolian depositional system). Paleocurrent data indicate that the source area of the Resplandecente Formation was the Sao Francisco craton region. The Macaubas Group represents the precursor basin of the Neo- proterozoic Aracuai orogen and the pre-glacial sedimentation is represented by two units: Matao and Duas Barras formations. The basal unit of the Macaubas Group - Matao Formation - is formed by lower breccia and conglom- erates and represents deposition under unstable conditions, covered by a thick package of fine sandstone (shallow marine transgressive sediments). Detrital zircon grains dated at ca. 1.16 Ga (U-Pb SHRIMP) limit the maximum age of the Matao Formation. Duas Barras Formation represents pre-glacial marine sediments. Both Sao Francisco craton and Congo craton could be the source for Duas Barras sediments.
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