Graduated in Geology (1980) with MSc degree from the Federal University of Rio de Janeiro, and PhD Degree in Geotectonics (Geochemistry and Geotectonic) from the University of São Paulo (1993). Post-doctoral studies were carried out from 2000 to 2001 in U/Pb Geochronology at the Geotop of the University of Quebec in Montreal (UQAM), besides many senior internships in Germany (UMainz) in 1997, Canada (Edmonton) 2011, Australia (ANU) in 2012, and Austria (2018-2019). Received important awards, such as best geology work and best doctoral thesis oriented by CREA
... Auteur(s) / Author(s). HEILBRON M. ; GONCALVES ML ; TEIXEIRA W. ; TROUW RAJ ; PADILHA AV ; KA... more ... Auteur(s) / Author(s). HEILBRON M. ; GONCALVES ML ; TEIXEIRA W. ; TROUW RAJ ; PADILHA AV ; KAWASHITA K. ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). Univ. estado Rio de Janeiro, dep. ... Mots-clés français / French Keywords. Amérique du Sud. ; Brésil. ; ...
The Juiz de Fora Complex (JFC) in the surroundings of Juiz de Fora (MG) town records a complex ge... more The Juiz de Fora Complex (JFC) in the surroundings of Juiz de Fora (MG) town records a complex geological evolution, with recurring deformational and high-grade metamorphic events from the Archean to the Lower Cambrian. The JFC comprises pre-1.8 Ga. granulite facies orthogneisses, migmatites and metabasites, with subordinated amphibolite facies orthogneisses. The JFC occurs as thrust sheets within post-1.8 Ga amphibolite facies metasedimentary rocks and within orthopyroxene-bearing migmatitic paragneisses of undetermined age. Recurring tectonic events led to the general obliteration of original textures, structures and paleogeography. Field and petrographic data allow the subdivision of the orthogranulites into mafic, intermediate, and felsic granulites. Imobile and Rare Earth elements suggest that (a) the mafic granulites are tholeiitic and that each sample represents different stages of differentiation of one parental magma, (b) the intermediate and felsic granulites are calc-alkaline, and (c) no petrogenetic link seems to exist between the tholeiitic and the calc-alkaline rocks, but some evidences point to possible link among the calc-alkaline rocks.
This paper presents and discusses new geochemical data from orthogneisses rocks of Paraiba do Sul... more This paper presents and discusses new geochemical data from orthogneisses rocks of Paraiba do Sul Complex (PSC) from the NW of the Rio de Janeiro State, denominated Quirino Unit. U-Pb geochronological data (carried out on GEOTOP-UQAM, Canada), displayed in Valladares (1996) and Machado et al. (1996), are also discuss. This Unit, as well the Metasedimentary Unit of PSC and intrusive brazilian granitoids, comprise the Paraiba do Sul Tectonic Domain (PSTD) or Upper Tectonic Domain, at the central segment of the Ribeira belt. The Quirino Unit occurs as extensive bodies of homogeneous gneisses of upper amphibolite facies metamorphism, with hornblende and or biotite comprising approximately 50% of the studied area and ca. 70% of the PSTD. This unit yields U-Pb zircon ages of 2185±3 Ma and 2169±3 Ma, temporally related to the Transamazonian event. Minimum ages of 2846 Ma and 2981 Ma (zircon U-Pb data) reveal the pre-existence of Archean crust as Pb source of part of the investigated gneisses. Geochemical studies of orthogneisses Quirino discriminate two calc-alkaline suites: one of medium to high-K and other of high-K, with enrichment in LILE. The chemical characteristics and the ages U-Pb allow to perform a tectonic correlation of the Quirino Unit with arc magmatic calc-alkaline granitoids, which were generated during the Transamazonian orogeny (2.2 - 1.9 Ga). Ages between 605-503 Ma (zircon and sphene U-Pb data) indicate reworking of Quirino Unit during Brazilian Orogeny (ca. 700-450 Ma).
... Auteur(s) / Author(s). HEILBRON M. ; GONCALVES ML ; TEIXEIRA W. ; TROUW RAJ ; PADILHA AV ; KA... more ... Auteur(s) / Author(s). HEILBRON M. ; GONCALVES ML ; TEIXEIRA W. ; TROUW RAJ ; PADILHA AV ; KAWASHITA K. ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). Univ. estado Rio de Janeiro, dep. ... Mots-clés français / French Keywords. Amérique du Sud. ; Brésil. ; ...
The Juiz de Fora Complex (JFC) in the surroundings of Juiz de Fora (MG) town records a complex ge... more The Juiz de Fora Complex (JFC) in the surroundings of Juiz de Fora (MG) town records a complex geological evolution, with recurring deformational and high-grade metamorphic events from the Archean to the Lower Cambrian. The JFC comprises pre-1.8 Ga. granulite facies orthogneisses, migmatites and metabasites, with subordinated amphibolite facies orthogneisses. The JFC occurs as thrust sheets within post-1.8 Ga amphibolite facies metasedimentary rocks and within orthopyroxene-bearing migmatitic paragneisses of undetermined age. Recurring tectonic events led to the general obliteration of original textures, structures and paleogeography. Field and petrographic data allow the subdivision of the orthogranulites into mafic, intermediate, and felsic granulites. Imobile and Rare Earth elements suggest that (a) the mafic granulites are tholeiitic and that each sample represents different stages of differentiation of one parental magma, (b) the intermediate and felsic granulites are calc-alkaline, and (c) no petrogenetic link seems to exist between the tholeiitic and the calc-alkaline rocks, but some evidences point to possible link among the calc-alkaline rocks.
This paper presents and discusses new geochemical data from orthogneisses rocks of Paraiba do Sul... more This paper presents and discusses new geochemical data from orthogneisses rocks of Paraiba do Sul Complex (PSC) from the NW of the Rio de Janeiro State, denominated Quirino Unit. U-Pb geochronological data (carried out on GEOTOP-UQAM, Canada), displayed in Valladares (1996) and Machado et al. (1996), are also discuss. This Unit, as well the Metasedimentary Unit of PSC and intrusive brazilian granitoids, comprise the Paraiba do Sul Tectonic Domain (PSTD) or Upper Tectonic Domain, at the central segment of the Ribeira belt. The Quirino Unit occurs as extensive bodies of homogeneous gneisses of upper amphibolite facies metamorphism, with hornblende and or biotite comprising approximately 50% of the studied area and ca. 70% of the PSTD. This unit yields U-Pb zircon ages of 2185±3 Ma and 2169±3 Ma, temporally related to the Transamazonian event. Minimum ages of 2846 Ma and 2981 Ma (zircon U-Pb data) reveal the pre-existence of Archean crust as Pb source of part of the investigated gneisses. Geochemical studies of orthogneisses Quirino discriminate two calc-alkaline suites: one of medium to high-K and other of high-K, with enrichment in LILE. The chemical characteristics and the ages U-Pb allow to perform a tectonic correlation of the Quirino Unit with arc magmatic calc-alkaline granitoids, which were generated during the Transamazonian orogeny (2.2 - 1.9 Ga). Ages between 605-503 Ma (zircon and sphene U-Pb data) indicate reworking of Quirino Unit during Brazilian Orogeny (ca. 700-450 Ma).
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