Contributions from the mantle and different crust reservoirs to the Neoproterozoic granitic magmatism in SE Brazil

• Grant number: 07/00635-5
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2007
• End date: August 31, 2010
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Valdecir de Assis Janasi
• Grantee: Valdecir de Assis Janasi
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The generation of granitic magmas of varied affinities show important links with processes initiated in the earth-s mantle. The contribution of the subcontinental mantle to the neoproterozoic granitic magmatism in southeast Brazil suggests that that enriched mantle domains identified in the Cretaceous-Tertiary tholeiitic and alkaline magmatism were generated or were already present during the orogenic processes of that age. This project focuses on the identification of the various sources involved in selected occurrences of the neoproterozoic granite magmatism in the State of Estado de São Paulo and nearby regions, with emphasis on the contribution of he subcontinental mantle. Detailed studies will be conducted in rocks of mantle derivation (potassic syenites and diorites); mantle xenoliths; and granitic s.l. plutons from the Agudos Grandes Batholith and the Paraíba Valley region, all of which were formed by diferent proportions of mantle and continental crust components. The tools that will be used include, besides field, petrography, lithogeochemistry and Sr-Nd isotopy, already available for part of the occurrences and to be complemented, microanalytical studies in minerals by LA-MC-ICPMS (Pb-Pb in K-felspar; Lu-Hf isotopy and U-Pb dating in zircon). As shown in the current literature, the integration of these techniques has excellent potential to identify and quantify the sources and processes involved in the generation of the parent magmas of the studied rocks. (AU)

Scientific publications

(13)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FLORISBAL, LUANA MOREIRA; BITENCOURT, MARIA DE FATIMA; JANASI, VALDECIR DE ASSIS; STOLL NARDI, LAURO VALENTIM; HEAMAN, LARRY M.. Petrogenesis of syntectonic granites emplaced at the transition from thrusting to transcurrent tectonics in post-collisional setting: Whole-rock and Sr-Nd-Pb isotope geochemistry in the Neoproterozoic Quatro Ilhas and Mariscal Granites, Southern Brazil. LITHOS, v. 153, n. SI, p. 53-71, NOV 15 2012. (07/02387-9, 07/00635-5)

FLORISBAL, LUANA MOREIRA; JANASI, VALDECIR DE ASSIS; BITENCOURT, MARIA DE FATIMA; STOLL NARDI, LAURO VALENTIM; HEAMAN, LARRY M.. Contrasted crustal sources as defined by whole-rock and Sr-Nd-Pb isotope geochemistry of neoproterozoic early post-collisional granitic magmatism within the Southern Brazilian Shear Belt, Camboriu, Brazil. Journal of South American Earth Sciences, v. 39, p. 24-43, NOV 2012. (07/02387-9, 07/00635-5)

ALMEIDA, VIDYA VIEIRA; JANASI, VALDECIR DE ASSIS; FALEIROS, FREDERICO MEIRA; SIMONETTI, ANTONIO; MORAES, RENATO. Composition and thermal evolution of the lithospheric mantle beneath the Ribeira Belt, SE Brazil: evidence from spinel peridotite xenoliths. INTERNATIONAL JOURNAL OF EARTH SCIENCES, v. 111, n. 3, p. 21-pg., 2022-02-18. (19/22084-8, 07/00635-5, 06/01925-4, 18/10012-0)

ALVES, ADRIANA; JANASI, VALDECIR DE ASSIS; CAMPOS NETO, MARIO DA COSTA. Sources of granite magmatism in the Embu Terrane (Ribeira Belt, Brazil): Neoproterozoic crust recycling constrained by elemental and isotope (Sr-Nd-Pb) geochemistry. Journal of South American Earth Sciences, v. 68, p. 19-pg., 2016-07-01. (07/00635-5)

FLORISBAL, LUANA MOREIRA; BITENCOURT, MARIA DE FATIMA; JANASI, VALDECIR DE ASSIS; STOLL NARDI, LAURO VALENTIM; HEAMAN, LARRY M.. Petrogenesis of syntectonic granites emplaced at the transition from thrusting to transcurrent tectonics in post-collisional setting: Whole-rock and Sr-Nd-Pb isotope geochemistry in the Neoproterozoic Quatro Ilhas and Mariscal Granites, Southern Brazil. LITHOS, v. 153, p. 19-pg., 2012-11-15. (07/02387-9, 07/00635-5)

CARVALHO, BRUNA BORGES; JANASI, VALDECIR DE ASSIS. Crystallization conditions and controls on trace element residence in the main minerals from the Pedra Branca Syenite, Brazil: An electron microprobe and LA-ICPMS study. LITHOS, v. 153, p. 16-pg., 2012-11-15. (07/00635-5)

CARVALHO, BRUNA BORGES; JANASI, VALDECIR DE ASSIS. Crystallization conditions and controls on trace element residence in the main minerals from the Pedra Branca Syenite, Brazil: An electron microprobe and LA-ICPMS study. LITHOS, v. 153, n. SI, p. 208-223, NOV 15 2012. (07/00635-5)

ALVES, ADRIANA; JANASI, VALDECIR DE ASSIS; CAMPOS NETO, MARIO DA COSTA. Sources of granite magmatism in the Embu Terrane (Ribeira Belt, Brazil): Neoproterozoic crust recycling constrained by elemental and isotope (Sr-Nd-Pb) geochemistry. Journal of South American Earth Sciences, v. 68, n. SI, p. 205-223, JUL 2016. (07/00635-5)

FLORISBAL, LUANA MOREIRA; JANASI, VALDECIR DE ASSIS; BITENCOURT, MARIA DE FATIMA; HEAMAN, LARRY M.. Space-time relation of post-collisional granitic magmatism in Santa Catarina, southern Brazil: U-Pb LA-MC-ICP-MS zircon geochronology of coeval mafic-felsic magmatism related to the Major Gercino Shear Zone. Precambrian Research, v. 216, p. 132-151, OCT 2012. (07/02387-9, 07/00635-5)

AZEVEDO SOBRINHO, JOSE M.; JANASI, VALDECIR A.; SIMONETTI, ANTONIO; HEAMAN, LARRY M.; SANTORO, JAIR; DINIZ, HELIO N.. The Ilha Anchieta Quartz Monzonite: the southernmost expression of ca. 500 Ma post-collisional magmatism in the Ribeira Belt. Anais da Academia Brasileira de Ciências, v. 83, n. 3, p. 891-906, SEP 2011. (07/00635-5)

CARVALHO, BRUNA BORGES; JANASI, VALDECIR DE ASSIS; HENRIQUE-PINTO, RENATO. Geochemical and Sr-Nd-Pb isotope constraints on the petrogenesis of the K-rich Pedra Branca Syenite: Implications for the Neoproterozoic post-collisional magmatism in SE Brazil. LITHOS, v. 205, p. 39-59, SEP 15 2014. (07/00635-5)

ALVES, ADRIANA; JANASI, VALDECIR DE ASSIS; SIMONETTI, ANTONIO; HEAMAN, LARRY. Microgranitic Enclaves as Products of Self-mixing Events: a Study of Open-system Processes in the Maua Granite, Sao Paulo, Brazil, Based on in situ Isotopic and Trace Elements in Plagioclase. JOURNAL OF PETROLOGY, v. 50, n. 12, p. 2221-2247, DEC 2009. (07/00635-5)

ALMEIDA, VIDYA V.; JANASI, VALDECIR DE A.; SVISERO, DARCY P.; NANNINI, FELIX. Mathiasite-loveringite and priderite in mantle xenoliths from the Alto Paranaiba Igneous Province, Brazil: genesis and constraints on mantle metasomatism. CENTRAL EUROPEAN JOURNAL OF GEOSCIENCES, v. 6, n. 4, p. 614-632, DEC 2014. (06/01925-4, 07/00635-5)