@InProceedings{PadilhaVitoPaulFuck:2019:GeCoNo,
author = "Padilha, Ant{\^o}nio Lopes and Vitorello, {\'{\I}}caro and
Paula, 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 = "Geoelectric Complexity of the Northern S{\~a}o Francisco Cratonic
Lithosphere, Central South America, Revealed by Magnetotellurics",
year = "2019",
organization = "AGU Fall Meeting",
abstract = "In the northern S{\~a}o Francisco Craton, central South America,
extensive Proterozoic and Phanerozoic sedimentary cover and lack
of deep-probing geophysical surveys have prevented to establish
unequivocally the cratonic character of the
Archean-Paleoproterozoic lithosphere. Broadband and long period
magnetotelluric (MT) soundings were conducted along a 580 km long
east-west profile in this region of the craton. 2D and 3D
inversions show extensive upper crustal horizontal conductors
beneath the intracratonic Irec{\^e} Basin and the Rio Preto
marginal belt, interpreted as associated with a combination of
high porosity and high fluid salinity in the sedimentary package
and fractured metasedimentary rocks at the top of the craton
basement during the Neoproterozoic marginal collision,
respectively. The deepest part of the crust presents pronounced
electrical complexity and heterogeneity, an indication that the
cratonic lithosphere was multiply reworked in the past by
tectonothermal events. Lithospheric resistive blocks bounded by
subvertical major conductive zones are identified. Constrained by
geochemical and isotopic data, these conductive interfaces are
interpreted as cryptic suture zones related to the large-scale
fusion of continents and microcontinents during the
Paleoproterozoic craton assembly. At upper mantle depths, high
conductivities are observed below most of the profile and
interpreted as effects of metasomatism or refertilization
processes with incompatible elements during Paleoproterozoic
subduction processes and subsequent
Mesoproterozoic-to-Neoproterozoic upwelling of deep fluids and
melts.",
conference-location = "San Francisco, CA",
conference-year = "09-13 dec.",
language = "en",
targetfile = "padilha_geoelectric.pdf",
urlaccessdate = "04 jun. 2024"
}