DEGEO - Departamento de Geologia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/8

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Resultados da Pesquisa

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    Unraveling multiple tectonic events and source areas in the intracratonic Bauru Basin through combined zircon geo and thermochronological studies.
    (2020) Dias, Airton Natanael Coelho; Chemale Júnior, Farid; Candeiro, Carlos Roberto dos Anjos; Lana, Cristiano de Carvalho; Guadagnin, Felipe; Sales, A. S. W.
    The application of Fission-Track Thermochronology (FTT), and U-Pb and Lu-Hf isotope analyses on the same zircon grains revealed the provenance and thermal/tectonic events related to the build-up and evolution of the Bauru Basin filling in Minas Gerais, Brazil. The U-Pb on detrital zircon reveals that the potential source areas were dominated by Brasiliano outcrops and subordinately, Paleoproterozoic, Mesoproterozoic, and Carboniferous sources. Positive εHf(t) signatures can characterize the Goias ´ magmatic Arc and older adjacent terranes as the most probable region that supplied the Bauru Basin. The FTT data display five main age peaks at 569, 337, 235, 132, and 83 Ma. They record the exhumation and denudation processes of Brasiliano and Gondwanide orogens and later, the Serra Geral magmatism of the South American Platform. A younger subordinate age (100–80 Ma) is recorded, and it may be associated with intense alkaline magmatism that occurred during the initial stages of basin deposition.
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    Sedimentological and paleoenvironmental constraints of the Statherian and Stenian Espinhaço rift system, Brazil.
    (2013) Santos, Marcelo Nascimento dos; Chemale Júnior, Farid; Dussin, Ivo Antonio; Martins, Maximiliano de Souza; Assis, Tiago A. R.; Jelinek, Andréa Ritter; Guadagnin, Felipe; Armstrong, Richard
    The Espinhaço Basin in eastern Brazil contains depositional sequences developed in the São Francisco paleoplate and its margins. Detailed mapping was conducted and combined with U–Pb detrital zircon dating to determine the sedimentological-stratigraphic framework, provenance and minimum and maximum ages of the syn-rift-deposits. The two cycles have minimum ages of 1192 and 923 Ma and maximum ages of 1785 and 1685 Ma. The first depositional cycle, represented by the Bandeirinha and São João da Chapada formations, is marked by contributions of Neoarchean and Paleoproterozoic detrital zircons. The second cycle, the diamond-bearing Sopa-Brumadinho Formation, also contains Mesoproterozoic zircons formed between 1300 and 1190 Ma, which suggests an additional external source of Grenvillian age, that was not previously recorded in the São Francisco Craton. The investigation of such Mesoproterozoic intraplate sedimentary records, provides clues to understanding the history of the Rodinia active margins and, therefore, the kinematic reconstruction of its paleoplates.