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Fabrício de Andrade Caxitohttp://lattes.cnpq.br/0090865315012529Antonio Carlos Pedrosa SoaresMonica da Costa Pereira Lavalle HeilbronsFernando Flecha de AlkmimLauro Cézar Montefalco de Lira SantosAlexandre UhleinJorge Geraldo Roncato Júniorhttp://lattes.cnpq.br/2092150488531727Raíssa Santiago Mendes2022-04-11T15:05:44Z2022-04-11T15:05:44Z2022-02-16http://hdl.handle.net/1843/40976O sistema orogênico Araçuaí-Ribeira (AROS) constitui uma parte da Província Mantiqueira desenvolvida durante a formação do Gondwana Ocidental no Neoproterozoico superior. Assim como diversos cinturões orogênicos formados durante o evento Pan-Africano/Brasiliano, o AROS é caracterizado por arcos magmáticos neoproterozoicos intra-oceânicos e continentais. O orógeno Ribeira compreende os arcos magmáticos intra-oceânicos a transicionais tonianoscriogenianos Serra da Prata e Rio Negro, e ambos os orógenos apresentam rochas correlacionáveis ao arco continental ediacarano Rio Doce, sugerindo uma evolução geodinâmica complexa. O batólito Caxixe, definido neste trabalho, é um batólito composto, multi-intrusão, amplamente distribuído no sul do Espírito Santo, com cerca de 110 Km de extensão e largura entre 12 e 21 Km. É composto principalmente por biotita-ortognaisses granodioríticos a graníticos, com afinidade geoquímica cálcioalcalina, metaluminosa a ligeiramente peraluminosa, magnesiana, de assinatura tipo I, com ligeiro enriquecimento em elementos terras raras leves (ETRL) em relação aos pesados (ETRP), anomalias positivas a levemente negativas de Eu e anomalias negativas de Nb-Ta. A maior parte do batólito Caxixe e dos plútons adjacentes apresenta idades entre 580 e 608 Ma, com parâmetros εHf(t), εNd(t) e 87Sr/86Sr diferenciados indicando importante contaminação crustal. Estas características são típicas de rochas do arco Rio Doce. Porém, rochas tonianas (840-860 Ma) ocorrem localmente neste batólito como roof pendants e megaxenólitos. Estas apresentam εHf(t), εNd(t) e 87Sr/86Sr tipicamente juvenis, plotando na curva do manto empobrecido. Estas rochas representam fragmentos de arcos de ilha, provavelmente a terminação norte do arco magmático Serra da Prata. Completando o edifício magmático do batólito Caxixe e adjacências, ocorrem também intrusões sin-colisionais de granadaleucogranitos a 575 Ma, intrusões máficas sin- a tardi-colisionais a 560 Ma e leucogranitos pós-colisionais a 503 Ma. Os paragnaisses aluminosos e os hornblendabiotita gnaisses que ocorrem como encaixantes destes plútons apresentam geoquímica semelhante a bacias relacionadas a arco magmático e espectro de idades U-Pb em zircão detrítico com picos principais entre 600 a 800 Ma, representando rochas sedimentares e volcaniclásticas provenientes do sistema de arcos magmáticos do AROS. Assim, os 360 Ma de atividade magmática e sedimentar registrados no batólito Caxixe e adjacências no sul do Espírito Santo são de enorme relevância parao entendimento da evolução tectônica do Gondwana Ocidental, registrando as etapas pré-, sin- e pós-colisionais do AROS. O modelo de evolução tectônica proposto envolve a docagem das rochas do arco magmático toniano na margem continental do paleocontinente Angola, seguida pela inversão da polaridade de subducção e desenvolvimento do arco continental Ediacarano Rio Doce por fusão da margem continental e dos terrenos acoplados. O processo evoluiu para a colisão entre os paleocontinentes São Francisco e Angola e o colapso orogênico no Cambriano.The Araçuaí-Ribeira orogenic system (AROS) constitutes a part of the Mantiqueira Province developed during the formation of Western Gondwana in the Late Neoproterozoic. Similar to several orogenic belts formed during the PanAfrican/Brazilian event, the AROS is characterized by intra-oceanic and continental Neoproterozoic magmatic arcs. The Ribeira orogen comprises the Serra da Prata and Rio Negro intra-oceanic Tonian-Cryogenian transitional arcs and both the Ribeira and Araçuaí orogens are characterized by the Ediacaran Rio Doce continental arc, suggesting a complex geodynamic evolution. The Caxixe batholith, defined in this work, is a multi-intrusion composite batholith widely distributed in the southern Espírito Santo state, with approximately 110 km in length and width ranging between 12 and 21 km. It is composed mainly of granodioritic to granitic biotite-orthogneisses, with calcalkaline geochemical affinity, metaluminous to slightly peraluminous, magnesian, type I, with slight enrichment in light rare earth elements (LREE) in relation to heavy ones (HREE), positive to slightly negative anomalies of Eu and negative anomalies of NbTa. Most of the Caxixe batholith and adjacent plutons have ages between 580 and 608 Ma, with differentiated εHf(t), εNd(t) and 87Sr/86Sr indicating important crustal contamination. These characteristics are typical of rocks of the Ediacaran Rio Doce arc. However, Tonian rocks (840-860 Ma) occur locally in this batholith as roof pendants and megaxenoliths. These present typically juvenile εHf(t), εNd(t) and 87Sr/86Sr ratios, plotting on the depleted mantle curve. These rocks represent fragments of juvenile island arcs, probably the northern end of the Serra da Prata magmatic arc. Completing the magmatic edifice of the Caxixe batholith and vicinities, there are also syn-collisional garnet-bearing leucogranites at ca. 575 Ma, syn- to tardicollisional mafic intrusions at ca. 560 Ma and post-collisional leucogranite intrusions of about 503 Ma. The peraluminous paragneisses and hornblende-biotite gneisses that occur as country rocks to these plutons present geochemistry similar to magmatic arc basins and U-Pb age spectra of detrital zircon with main peaks between 600 and 800 Ma, indicating derivation from sedimentary and volcaniclastic rocks related to the magmatic arc systems. Thus, the 360 Ma of magmatic and sedimentary activity recorded in the Caxixe batholith and its surroundings in the southern Espírito Santo state are of enormous relevance for the understanding of the tectonic evolution of Western Gondwana, recording the pre-, syn- and post-collisional stages of theorogenic building of the AROS. We propose a model of tectonic evolution with the docking of the Tonian magmatic arc rocks in the passive continental margin of the Angola paleocontinent, followed by the subduction polarity inversion and development of the Rio Doce continental arc in the Ediacaran by melting of the continental margin and docked terranes. This was followed by collision between the São Francisco and Angola paleocontinents and orogenic collapse in the Cambrian.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorporUniversidade Federal de Minas GeraisPrograma de Pós-Graduação em GeologiaUFMGBrasilIGC - DEPARTAMENTO DE GEOLOGIATempo geológicoGeoquímica - Espírito Santo (Estado)Orogenia - Espírito Santo (Estado)Geologia isotópica - Espírito Santo (Estado)Geocronologia LA-ICPMS e SHRIMP U-PbGeoquímica Isotópica Hf-Nd-SrArco MagmáticoRoof-pendantsOrogenia BrasilianaEvolução crustal, geocronologia e geologia isotópica do Orógeno Araçuaí-Ribeira (AROS) no sul do Espírito Santoinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGORIGINAL19 - Tese de doutorado - Raíssa Santiago Mendes.pdf19 - Tese de doutorado - Raíssa Santiago Mendes.pdfTese de doutorado - Raíssa Santiago Mendesapplication/pdf10548814https://repositorio.ufmg.br/bitstream/1843/40976/1/19%20-%20Tese%20de%20doutorado%20-%20%20Ra%c3%adssa%20Santiago%20Mendes.pdf7a129f07cbfde69d657a149dadc99b96MD51LICENSElicense.txtlicense.txttext/plain; charset=utf-82118https://repositorio.ufmg.br/bitstream/1843/40976/2/license.txtcda590c95a0b51b4d15f60c9642ca272MD521843/409762022-04-11 12:05:44.996oai:repositorio.ufmg.br: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ório InstitucionalPUBhttps://repositorio.ufmg.br/oaiopendoar:2022-04-11T15:05:44Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG)false
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