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@InProceedings{PadilhaVitoPádu:2015:ThMaIm,
               author = "Padilha, Antonio Lopes and Vitorello, {\'{\I}}caro and 
                         P{\'a}dua, Marcelo Banik",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {University 
                         of Arizona} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)}",
                title = "Three-dimensional magnetotelluric imaging of crustal structure 
                         beneath the Central Domain of the Borborema Province, NE Brazil",
                 year = "2015",
         organization = "IUGG General Assembly, 26.",
             abstract = "The Borborema province, in northeast Brazil, consists of a complex 
                         set of crustal blocks of different ages, origin and evolution, 
                         with final amalgamation during the late Neoproterozoic Brasiliano 
                         orogeny. Its Central Domain is characterized by elongate NE-SW 
                         terranes largely affected by the Brasiliano metamorphic 
                         overprinting and by a suite of early Neoproterozoic metavolcanic 
                         rocks reflecting a distinct tectonic event (Cariris Velhos). 
                         Magnetotelluric (MT) data were collected at 64 stations along four 
                         profiles across this central region of the province to assess its 
                         deep electrical resistivity structure. Dimensionality analysis 
                         shows that the subsurface is electrically dominated by 3D 
                         structure, and 3D inversions of the full impedance tensor and 
                         vertical magnetic transfer function (tipper) were carried out. The 
                         dominant features in the final model are north-dipping crustal 
                         conductors, which can be correlated between the different MT 
                         profiles and cross contrasting terranes at the surface of the 
                         province. Considering the geometry and distribution of the 
                         conductors, they are interpreted as reflecting remnants of a 
                         pre-Neoproterozoic north-directed subduction zone with enhanced 
                         conductivity associated with graphitized biogenic material in 
                         metasedimentary rocks originally deposited in a restricted oceanic 
                         environment and subsequently metamorphosed and introduced into the 
                         deep crust by the subduction of the oceanic lithosphere. As the 
                         extent of crustal remobilization by the Brasiliano event seems to 
                         be restricted to the brittle upper crust, it is proposed that the 
                         Neoproterozoic geodynamic evolution in this domain of the 
                         Borborema Province occurred in an intracontinental setting.",
  conference-location = "Prague, Czech Republic",
      conference-year = "22 June - 02 July",
        urlaccessdate = "28 mar. 2024"
}


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