U-Pb (LA-ICPMS) zircon ages and Nd isotopes for granitoids of the Tamboril-Santa Quitéria Complex, Ceará Central Domain[/title]: [subtitle]implication for neoproterozoic syncollisional magmatism in north Borborema Province

Abstract

The Tamboril-Santa Quitéria Complex (TSQC) is one of the largest Neoproterozoic plutonic manifestations in the north Borborema Province (NE Brazil). It represents an anatectic/igneous association characterized by a number of magmatic pulses that occurred in the 650-610 Ma interval. In this paper, we present U-Pb (LA-MC-ICP-MS) zircon ages and Nd isotopes for quartz monzonites and quartz diorites of the southern part of TSQC. The quartz monzonites belong to a hybrid granitoid association, including monzonites, syenites and quartz syenites, all with abundant mafic magmatic enclaves. A quartz monzonite sample yielded a U-Pb zircon age of 634 ± 10 Ma and a TDM age of 2.69 Ga. The quartz diorites are much more homogeneous in composition and yielded a U-Pb zircon age of 618 ± 23 Ma and a TDM age of 2.19 Ga. The presence of coeval mantle-derived magmatism and diatexites (crustal anatexis) post-dating high-pressure metamorphism (ca. 650 Ma), and together with high-temperature metamorphism (ca. 630-610 Ma), suggests that this large magmatic manifestation evolved in a collisional setting, probably related to slab breakoff during the Western Gondwana amalgamation.Keywords: Borborema Province; Neoproterozoic magmatism; Continental collision. ResumoO Complexo Tamboril Santa-Quitéria (CTSQ) é uma das maiores manifestações plutônicas do Neoproterozoico na porção norte da Província Borborema (NE Brasil). Corresponde a uma associação granito-migmatítica envolvendo granitoides diversos no intervalo de 650-610 Ma. Neste trabalho, são apresentadas idades U-Pb (LA-MC-ICP-MS) em zircão e isótopos de Nd para quartzo-monzonitos e quartzo-dioritos da porção sul do CTSQ. Os quartzo-monzonitos fazem parte de uma associação de granitoides híbridos, incluindo monzonitos, sienitos e quartzo-sienitos, todos com abundante ocorrência de enclaves máficos magmáticos. Para uma amostra de quartzo-monzonito, foram obtidas idade U-Pb em zircão de 634 ± 10 Ma e idade TDM de 2,69 Ga. Os quartzo-dioritos são bem mais homogêneos em composição, e, para uma amostra, foram obtidas idade U-Pb em zircão de 618 ± 23 Ma e TDM de 2,19 Ga. A presença simultânea de magmatismo com afinidade mantélica e diatexitos (fusão crustal), após o metamorfismo de alta-pressão (ca. 650 Ma) e junto com o metamorfismo de alta temperatura (ca. 630 -610 Ma), sugere que esta grande manifestação magmática evoluiu em um ambiente colisional, provavelmente associado ao processo de slab breakoff durante a amalgamação da porção oeste do supercontinente Gondwana.Palavras-chave: Província Borborema; Magmatismo neoproterozoico; Colisão continental.

Constraints from zircon geochronology on the tectonic evolution of the Borborema Province (NE Brazil): Widespread intracontinental Neoproterozoic reworking of a Paleoproterozoic accretionary orogen

“…There are, however, important differences, especially for younger periods. Cear a Central Domain Amaral et al, 2012Araújo et al, 2012Archanjo et al, 2008Castro et al, 2012Costa et al, 2013Fetter et al, 2000Martins et al, 2009Nogueira, 2004Santos et al, 2008a,b Silva et al, 2002Araújo et al, 2010, 2012Garcia et al, 2014Kalsbeek et al, 2013 Rio Grande do Norte Domain Archanjo et al, 2013Dantas et al, 2004Fetter et al, 2000Guimarães et al, 2009Hackspacher et al, 1990Hollanda et al, 2008, 2011 submitted for publication Medeiros et al, 2012Souza et al, 2007Van Schmus et al, 1995Viegas et al, 2014Kalsbeek et al, 2013Van Schmus et al, 2003 Central Subprovince Plutonic rocks Metasedimentary rocks Almeida et al, 2002Archanjo and Fetter, 2004Archanjo et al, 2008Brito Neves et al, 2001aBrito Neves et al, 2001bBrito Neves et al, 2003Brito Neves et al, 2013Cruz and Accioly, 2012Ferreira et al, 2011Guimarães et al, 2004Guimarães et al, 2011Guimarães et al, 2012Hollanda et al, 2010Lages et al, 2013Leite et al, 2000…”

Geochemistry and U–Pb zircon ages of plutonic rocks from the Algodões granite-greenstone terrane, Troia Massif, northern Borborema Province, Brazil: Implications for Paleoproterozoic subduction-accretion processes

“…The high-grade metamorphism in CCD is represented by local high-pressure granulite facies (~650e640 Ma) (Castro, 2004;Amaral et al, 2012), with some relict eclogite facies (Santos et al, 2009b), and subsequent regional high-temperature granulite/ amphibolite metamorphism (630e610 Ma) (Arthaud, 2007;Amaral et al, 2012). Neoproterozoic magmatism in CCD is mainly represented by the (650e610 Ma) Tamboril-Santa Quit eria arc/ collisional complex (Fetter et al, 2003;Araújo et al, 2012b;Costa et al, 2013;Padilha et al, 2013;Araujo et al, 2014), followed by a large syn-transcurrent batholith emplacement (e.g., Quixad aQuixeramobim) at ca. 590e560 Ma (Fetter, 1999;Nogueira, 2004).…”

The Neoproterozoic Ceará Group, Ceará Central domain, NE Brazil: Depositional age and provenance of detrital material. New insights from U–Pb and Sm–Nd geochronology

“…660 and 614 Ma predominantly Costa et al, 2013;Araújo et al, 2014), however one UePb age of 833 ± 6.1 Ma indicate an older evolution for the Santa Quit eria magmatic arc (Araújo et al, 2014). SmeNd TDM model ages are Meso-to Neoproterozoic, and 3Nd(600) values vary between À3 and þ3 .…”