Made available in DSpace on 2015-03-13T17:08:23Z (GMT). No. of bitstreams: 1 LindaraySC.pdf: 4257838 bytes, checksum: 9412fe333ae2e7c2ddef65c89e08a35e (MD5) Previous issue date: 2009-06-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The study area is located at the eastern-central portion of the Serid? Belt, on the interface between the Serid? Group Metasediments and the crystalline basement rocks of the Caic? Complex (RN). Petrographic and geochemical data allow us to define aspects related to the genesis and evolution of the Serra Verde Pluton magmas, which composes the goal of this dissertation The Serra Verde Pluton is a stock with outcropping area of about 25 km?, which is intrusive into metasedimentary sequence and the basement gneisses. The pluton intrusion is sintectonic to the Brasiliano event, elongated along the NE direction, developing a cornue geometry. The rock is a monzogranite mainly composed by K-feldspar, plagioclase and quartz, which usually compose more than 85% of the modal analisys. The main mafic mineral is the biotite, while amphibole, sphene, epidote, opaque minerals, allanite, zircon and apatite occur as accessory minerals. It features still a latemagmatic paragenesis composed by chlorite, granular epidote, carbonates and muscovite, developed through the percolation of late CO2 and H2O rich fluids. Chemically, the Serra Verde Pluton rocks may be classified as metaluminous, of calc-alkaline affiliation, sometimes showing trondhjem?tic characteristics, with high Na2O (>4,5%), Sr (>400ppm) and Ba (>800ppm) and low K2O (&#8804;3,0%), MgO (<1,0%), TiO2 (<0,5%), Rb (<90ppm), Y (&#8804;16ppm) and Zr (&#8804;13ppm). Micropetrographic evidences (mineral assembly and microtextures) indicate that the magma evolution occurred in moderated to high fO2 conditions, above the FMQ buffer. Thermo-barometric data obtained by minor elements geochemistry and the CIPW data, suggest a final/minimal pressure crystallization for the Serra Verde Pluton samples of about 3 to 5 kbar, liquidus temperature around 800o C, solidus temperature between 680o and 660o C. This data is compatible with those observed by many authors for the Neoproterozoic granites of the Serid? Belt. The group of analyzed data (Petrographic, microtextural and geochemical), suggests that the dominant process of the generation and evolution of the Serra Verde Granite magma was the fractional crystallization, probably from basement quartz-dioritic and tonalitic orthogneisses source / A ?rea estudada situa-se na por??o centro-leste da Faixa Serid?, na interface dos metassedimentos do Grupo Serid? e as rochas do embasamento cristalino do Complexo Caic? (RN). Dados petrogr?ficos e qeoqu?micos permitem definir os aspectos relativos ? g?nese e evolu??o do(s) magma(s) do Pl?ton Serra Verde, que constitui o alvo desta Disserta??o de Mestrado. O Pl?ton Serra Verde constitui um stock com ?rea aflorante de aproximadamente 25 Km2, intrusivo na seq??ncia metassedimentar e nos gnaisses do embasamento. Este pl?ton corresponde a uma intrus?o sintect?nica ao evento brasiliano, alongada na dire??o NE, com geometria en cornue. Trata-se de um monzogranito cuja assembl?ia mineral ominante ? composta por K-feldspato, plagiocl?sio e quartzo, que usualmente somam mais de 85% modal. Tem como m?fico principal a biotita, enquanto que anfib?lio itanita, ep?doto, opacos, allanita, zirc?o e apatita s?o os acess?rios. Apresenta ainda uma parag?nese tardi-magm?tica constiut?da de clorita, ep?doto granular, carbonato e muscovita, desenvolvida a partir da atua??o de flu?dos tardios ricos em CO2 e H2O. Quimicamente, as rochas do Pl?ton Serra Verde podem ser classificadas como metaluminosas, de filia??o c?lcio-alcalina, por vezes com caracter?sticas de associa??es trondhjem?ticas, com altos teores de Na2O (>4,5%), Sr (>400ppm) e Ba (>800ppm), e baixos teores de K2O (&#8804;3,0%), MgO (<1,0%), TiO2 (<0,5%), Rb (<90ppm), Y (&#8804;16ppm) e Zr (&#8804;13ppm). Evid?ncias micropetrogr?ficas (assembl?ias minerais e microtexturais) indicam que a evolu??o do magma ocorreu em condi??es de fO2 moderadas a elevadas, acima do tamp?o FMQ. Dados termobarom?tricos obtidos atrav?s da geoqu?mica de elementos menores, tra?os e dados normativos CIPW sugerem uma press?o final/m?nima de cristaliza??o para as amostras do Pl?ton Serra Verde em torno de 3 a 5 kbar, temperatura do l?quidus em torno de 800?C, e temperatura do solidus em torno 680 a 660?C. Estes dados s?o compat?veis com os observados por diversos autores em granit?ides neoproteroz?icos do Dom?nio Serid?. O conjunto de dados analisados (petrogr?ficos microtexturais e geoqu?micos), sugerem ainda que o processo dominante na gera??o e evolu??o do magma do granito Serra Verde se deu por cristaliza??o fracionada, sendo ortognaisses quartzo dior?ticos a tonal?ticos do complexo do embasamento, prov?veis candidatos para sua fonte