Geochemical Studies In The Proterozoic Metamorphic Terrane Of The Guaxupé Massif, Minas Gerais, Brazil. A Discussion On Large Ion Lithophile Element Fractionation During High-grade Metamorphism

The trace element composition of high-grade metamorphic rocks in the Guaxupé Massif is investigated. The large ion lithophile element composition is compared in both the granulite facies rocks and the associated amphibolite facies gneisses. The K, Rb, Th contents in the granulite facies rocks from other parts of Brazil show that the depletion of these elements is variable. The covariance of KRb ratios with K suggest the importance of mineralogical control, protolith composition, nature of fluid etc. The distribution of U and Th appears to indicate the protolith composition of the rock types. © 1987.3616579Allen, Metasomatism of a depleted granulite facies terrain in the Arunta Block, central Australia-I. Geochemical evidence (1979) Contrib. Mineral. Petrol., 71, pp. 85-98Allis, A heat production model for the stable continental crust (1979) Tectonophysics, 57, pp. 151-165Barbey, Cuney, K, Rb, Sr, Ba, U and Th geochemistry of the Lapland granulites (Fennoscandia) (1982) LILE fractionation controlling factors, 81, pp. 304-316. , Contrib. Mineral. PetrolChoudhuri, Paragenesis and stability of hornblende in charnockitic gneiss and mafic granulite: example from Minas Gerais (1984) An. Acad. Brasil. Cienc., 56, pp. 155-161Choudhuri, Szabo, Metamorphosed and differentiated basic intrunsives in the Poço Fundo Area, South Minas Gerais (1982) An. XXXII Congr. Bras. Geol. Salvador., 2, pp. 426-439Choudhuri, Fiori, Bettencourt, Charnockitic gneisses and granulites of the Botelhos region, Southern Minas Gerais (1978) An XXX Congr. Bras. Geol., Recife, 1, pp. 1236-1249Collerson, Contrasting patterns of KRb distribution in Precambrian high grade metamorphic rocks from central Australia (1975) Journal of the Geological Society of Australia, 22, pp. 145-158Coolen, Chemical petrology of the Furua granulite complex Southern Tanzania (1980) GUA Papers of Geology, Amsterdam, Ser., 1 (13), p. 258Cordani, Iyer, Geochronological investigation on the Precambrian granulitic terrain of Bahia, Brazil (1979) Precambrian Res., 9, pp. 255-274De Almeida, Hasui, de Brito Neves, The upper Precambrian of South America (1976) Bol. Inst. Geoc. Univ. São Paulo, 7, pp. 45-80De Almeida, Hasui, de Brito Neves, Fuck, Brazilian structural provinces: an introduction (1981) Earth Sci. Rev., 17, pp. 1-29De Oliveira, Petrologia das rochas metamórficas da região de São José do Rio Pardo (1973) SP. Rev. Bras. Geoc., 3, pp. 257-278De Oliveira, Bulk geochemistry of the Paraíba do Sul granulitic belt (1982) Anais do Isap: International Symposium on Archaean and Early Proterozoic Geologic Evolution and Metallogenesis, 12, pp. 369-374. , Brasileira de Geologia and Secretaria da Minas e Energia do Estado Sociedade, da Bahia, Rev. Bras. GeocDe Oliveira, Considerações sobre a evolução do complex Varginha (1984) An. XXXIII Congr. Bras. Geol., Rio de Janeiro, 5, pp. 2302-2304Departamento Nacional da Produção Mineral, Projeto Sapucaí Relatório de geologia do SW estado de Minas Gerais e NE do estado de São Paulo (1979) MME DNPM Série 4, Sec. Geol. Bras., p. 299. , no. 2 BrasíliaDostal, Capedri, Uranium in metamorphic rocks (1978) Contrib. Mineral. Petrol., 66, pp. 409-414Drury, The geochemistry of Precambrian granulite facies rocks from the Lewisian complex of Tiree, Inner Hebrides, Scotland (1973) Chem. Geol., 11, pp. 167-188Dupuy, Leyroloup, Vernieres, The lower continental crust of the Massif Central (Bournac, France) with special references to REE, U and Th composition, evolution, heat-flow production (1979) Origin and Distribution of the Elements, pp. 401-415. , L.H. Ahrens, Pergamon, New YorkEbert, Beitrag zur Gliederung des Präkambriums in Minas Gerais (1956) Geologische Rundschau, 45, pp. 471-521Ebert, Baustil und Regionalmetamorphose in präkambrischen Grundgebirge Brasiliens (1962) Tcherm. Min. Pet. Mitt., 8, pp. 49-81Fahrig, Eade, Adams, Abundance of radioactive elements in crystalline shield rocks (1967) Nature, 214, pp. 1002-1003Fernandes, Geoquímica do U, Th e outros elementos litófilos em rochas de alto grau de metamorfismo do “Maciço de Guaxupé”, Sul de Minas Gerais (1982) MSc. Thesis, p. 69. , IPEN, São Paulo, (Unpublished)Field, Clough, KRb ratios and metasomatism in metabasites from a Precambrian amphibolite-granulite transition zone (1976) J. Geol. Soc. London, 132, pp. 277-288Figueiredo, Geochemistry of High-Grade Metamorphic Rocks, Northeastern Bahia, Brazil (1980) Ph.D. Thesis, p. 211. , Dep. Geol., Univ. Western Ont, (Unpublished)Figueiredo, Geochemistry of high-grade complexes of Bahia State Brazil (1982) Anais do Isap: International Symposium, 12, pp. 307-312. , Brasileira de Geologia and Secretaria das Minas e Energia do Estado Sociedade, da Bahia, Rev. Bras. GeocFiori, Choudhuri, Fases de migmatização e dobramentos superpostos nas rochas granulíticas e nos migmatitos de Serrania e Machado, MG (1979) 2nd Symp. Reg. Geol, 1, pp. 47-58. , Rio Claro, SPGasparini, Montovani, Geochemistry of charnockites from São Paulo State Brazil (1979) Earth Planet. Sci. Lett, 42, pp. 311-320Glassley, The role of CO2 in the chemical modification of deep continental crust (1983) Geochim. Cosmochim. Acta, 47, pp. 597-616Gray, The geochemistry of central Australian granulites in relation to the chemical and isotopic effects of granulites facies metamorphism (1977) Contrib. Mineral. Petrol., 65, pp. 79-89Gray, Oversby, The behaviour of lead isotopes during granulite facies metamorphism (1972) Geochim. Cosmochim. Acta, 36, pp. 939-952Haack, On the content and vertical distribution of K, Th and U in the continental crust (1983) Earth Planet. Sci. Lett., 62, pp. 360-366Haralyi, Hasui, Mioto, Hamza, Rodrigues, Ensaio sobre a estruturação crustal do Estado de Minas Gerais com base na informação geofísica e geologica (1985) Contribuições à geologia e à petrologia. Bol. Especial. Soc. Bras. Geol. Núcleo de Minas Gerais, pp. 71-94Heier, Adams, Concentration of radioactive elements in deep crustal material (1965) Geochim. Cosmochim. Acta, 29, pp. 53-61Heier, Thorensen, Geochemistry of high grade metamorphic rocks, Lofoten-Vesteralen, North Norway (1971) Geochim. Cosmochim. Acta, 35, pp. 89-99Iyer, Kutty, Geochemical comparison of Archaean granulites in India with Proterozoic granulites in Canada (1978) Archaean Geochemistry, pp. 269-288. , B.F. Windley, S.M. Naqvi, Elsevier, AmsterdamIyer, Granulites and Associated Schists from Northern Strangways Range, Central Australia (1974) Geochemical and Isotopic Studies, p. 231. , Ph.D. Thesis, Dep. Geol., Univ. Queensland, Australia, (Unpublished)Iyer, Choudhuri, Vasconcellos, Cordani, Radioactive element distribution in the Archaean terrane of Jequié Bahia, Brazil (1984) Contrib. Mineral. Petrol., 85, pp. 95-101Janardhan, Newton, Smith, Ancient crustal metamorphism at low PH2O: charnockite formation at Kabbaldurga, South India (1979) Nature, 278, pp. 511-514Kaul, Teixeira, Archaean and early Proterozoic complexes of Santa Catarina, Paraná and São Paulo States, southeastern Brazil (1982) Rev. Bras. Geoc., 12, pp. 172-182Lambert, Chamberlain, Holland, The geochemistry of Archaean rocks (1976) The Early History of the Earth, pp. 377-387. , B.F. Windley, Wiley, LondonLewis, Spooner, KRb ratios Precambrian granulite terranes (1973) Geochim. Cosmochim. Acta, 37, pp. 1111-1118Moine, La Roche, Touret, Structures géochimiques et zonéagraphie métamorphique dans la Précambrien catazonal du Sud de la Norvège (région d'Arendall) (1972) Sci. Terre, 17, pp. 131-164Moorbath, Age and isotope constraints for the evolution of Archaean crust (1976) The Early History of the Earth, pp. 351-360. , B.F. Windley, Wiley, LondonMoorbath, Welke, Lead isotope studies on igneous rocks from the isle of Syke, Northeast Scotland (1969) Earth Planet. Sci. Lett., 5, pp. 230-271Nardi, Hartmann, Estudo geoquímico de rochas granulíticas do Escudo Sulriograndense (1980) Acta, Geol. Leopol., 4, pp. 3-18Reynolds, Jr., Matrix corrections in trace elements analysis by X-ray fluorescence: estimation of the mass absorption coefficient by Compton scattering (1963) Am. Mineral., 48, pp. 1133-1143Reynolds, Jr., Estimation of mass coefficient by Compton scattering improvements and extension of method (1967) Am. Mineral., 52, pp. 1493-1502Rollinson, Windley, Selective elemental depletion during metamorphism of Archaean granulites, Scourie, NW Scotland (1980) Contrib. Mineral. Petrol., 72, pp. 257-263Rudnick, Mclennan, Taylor, Large ion lithophile elements in rocks from high pressure granulite facies terrains (1985) Geochim. Cosmochim. Acta, 49, pp. 1645-1655Schobbenhaus, de Almeida Campos, Derze, Asmus, Geologia do Brasil-Texto explicativo do mapa geológico do Brasil (1984) 1: 2 500 000 DNPM Public, , BrasíliaShaw, U, Th and K in the Canadian Precambrian shield and possible mantle compositions (1967) Geochim. Cosmochim. Acta, 31, pp. 1111-1113Shaw, A review of KRb fractionation trends by covariance analysis (1968) Geochim. Cosmochim. Acta, 32, pp. 573-601Sighinolfi, Investigations into deep crustal levels: fractionating effects and geochemical trends related to high-grade metamorphism (1971) Geochim. Cosmochim. Acta, 35, pp. 1005-1021Sighinolfi, Sakai, Uranium and thorium in Archaean granulite facies terrains of Bahia (Brazil) (1977) GEOCHEMICAL JOURNAL, 11, pp. 33-39Sighinolfi, Figueiredo, Fyfe, Kronberg, Tanner Oliveira, Geochemistry and petrology of the Jequié granulitic complex (Brazil) an Archaean basement complex (1981) Contributions to Mineralogy and Petrology, 78, pp. 263-271Smithson, Brown, A model for the lower continental crust (1977) Earth Planet. Sci. Lett., 35, pp. 134-144Tarney, Windley, Chemistry, thermal gradients and evolution of the lower continental crust (1977) J. Geol. Soc. London, 134, pp. 153-172Wernick, de Oliveira, Composition of Archaean granulites from southern Brazil and its implications for the nature of the early crust (1982) Anais do Isap: International Symposium on Archaean and Early Proterozoic Geologic Evolution and Metallogenesis, 12, pp. 403-409. , Brasileira de Geologia and Secretaria das Minas e Energia do Estado Sociedade, da Bahia, Rev. Bras. GeocWilson, Comparison of some of the feature and tectonic setting of Archaean and Proterozoic granulites, with particular reference to Australia (1978) Archaean Geochemistry, pp. 241-267. , B.F. Windley, S.M. Naqvi, Elsevier, AmsterdamWoodford, Plymetamorphism in Granulites from the northeastern Strangways Range, Central Australia (1974) Ph.D. Thesis, p. 454. , Dep. Geol., Univ. Queensland, Australia, (unpublished