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@Article{PadilhaVitoPáduFuck:2019:MaImPa,
               author = "Padilha, Antonio Lopes and Vitorello, {\'{\I}}caro and 
                         P{\'a}dua, Marcelo Banik de and Fuck, Reinhardt A.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Universidade de Bras{\'{\i}}lia 
                         (UnB)}",
                title = "Magnetotelluric images of Paleoproterozoic accretion and 
                         Mesoproterozoic to Neoproterozoic reworking processes in the 
                         northern S{\~a}o Francisco Craton, central-eastern Brazil",
              journal = "Precambrian Research",
                 year = "2019",
               volume = "333",
                pages = "105416",
                month = "Oct.",
             keywords = "Northern S{\~a}o Francisco Craton, Magnetotellurics, 
                         Paleoproterozoic accretion, Mantle refertilization.",
             abstract = "Broadband and long period magnetotelluric (MT) data were collected 
                         along an east-west oriented, 580-km-longprofile across the 
                         northern S{\~a}o Francisco Craton where extensive Proterozoic and 
                         Phanerozoic sedimentarycover and lack of deep-probing geophysical 
                         surveys have prevented to establish unequivocally the 
                         cratoniccharacter of the Archean-Paleoproterozoic lithosphere. 
                         Following dimensionality analyses, the MT dataset wasinterpreted 
                         using both 2-D and 3-D inversion procedures. The near-surface 
                         structure is better resolved in the 2-Dmodel due to itsfiner 
                         resolution. A huge upper crustal conductor is found all along the 
                         shallow earlyNeoproterozoic Irec{\^e} Basin in the central domain 
                         of the craton, extending laterally for approximately 150 kmand 
                         restricting signal propagation below the basin. Its high 
                         conductance is explained by a combination of highporosity and 
                         highfluid salinity in the sedimentary package. Another upper 
                         crustal conductor is observed on thewest side of the profile, 
                         interpreted as fractured metasedimentary rocks of the Rio Preto 
                         belt thrusted on top ofthe craton basement during Neoproterozoic 
                         marginal collision. The 3-D model explains significantly better 
                         themeasured data related to deep structure. Contrary to what is 
                         expected for a stable cratonic block, the geoelectricmodel shows 
                         pronounced electrical complexity and heterogeneity, an indication 
                         that the cratonic lithospherewas multiply reworked in the past by 
                         tectonothermal events. Different lithospheric resistive blocks 
                         bounded bymajor conductive zones are identified. Constrained by 
                         geochemical and isotopic data, these vertical conductiveinterfaces 
                         are interpreted as cryptic suture zones due to large-scale 
                         amalgamation of continents and micro-continents leading to the 
                         assembly of the S{\~a}o Francisco Craton in the Paleoproterozoic. 
                         The conductivity en-hancement is more likely explained by 
                         emplacement of sulfides along previous suture zones during 
                         maficmagmatism. At upper mantle depths, high conductivity observed 
                         below most of the profile indicates that me-tasomatism or 
                         refertilization processes with incompatible elements caused by the 
                         Paleoproterozoic subductingslabs and Mesoproterozoic to 
                         Neoproterozoic upwelling of deepfluids and melts reworked this 
                         portion of thecraton mantle.",
                  doi = "10.1016/j.precamres.2019.105416",
                  url = "http://dx.doi.org/10.1016/j.precamres.2019.105416",
                 issn = "0301-9268",
             language = "en",
           targetfile = "padilha_magnetotelluric.pdf",
        urlaccessdate = "17 abr. 2021"
}


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