Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:29Z No. of bitstreams: 1 KeylaThayrinneOliveiraCoimbra_DISSERT.pdf: 21184106 bytes, checksum: cd5ec307de2601ec684062fb512f9165 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-29T00:13:31Z (GMT) No. of bitstreams: 1 KeylaThayrinneOliveiraCoimbra_DISSERT.pdf: 21184106 bytes, checksum: cd5ec307de2601ec684062fb512f9165 (MD5) / Made available in DSpace on 2016-07-29T00:13:31Z (GMT). No. of bitstreams: 1 KeylaThayrinneOliveiraCoimbra_DISSERT.pdf: 21184106 bytes, checksum: cd5ec307de2601ec684062fb512f9165 (MD5) Previous issue date: 2015-08-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O plut?o Bom Jardim de Goi?s (PBJG) ? um corpo de geometria semi-circular, situado na por??o central da Prov?ncia Tocantins, intrusivo em ortognaisses e metassupracrustais do Arco Magm?tico Aren?polis. Estas metasupracrustais apresentam um bandamento / xistosidade de ?ngulo baixo a moderado, definido por micas, andalusita, silimanita e cordierita, caracterizando um metamorfismo na f?cies anfibolito. Tal estrutura ? truncada pela coloca??o das rochas do PBJG. O car?ter abrupto dos contatos e a aus?ncia de estruturas d?cteis demonstram que a intrus?o se deu em crosta relativamente fria. Em termos petrogr?ficos, o plut?o comp?e-se de monzodioritos, tonalitos e granodioritos, seguindo a trajet?ria evolutiva c?lcio-alcalina de pot?ssio baixo a intermedi?rio. As rochas do PBJG possuem hornblenda e biotita como fases m?ficas principais, al?m da ocorr?ncia subordinada de clinopirox?nio, titanita, ep?doto e opacos. Diques tardios de leucogranito cont?m apenas biotita como mineral acess?rio relevante. Uma data??o U-Pb em zirc?o do monzodiorito forneceu uma idade de 550?12 Ma (MSWD = 1,06). Dados litogeoqu?micos e de qu?mica mineral sugerem que as rochas em foco s?o c?lcio-alcalinas, tendo evolu?do por cristaliza??o fracionada de minerais c?lcicos e ferro-magnesianos, sob condi??es de alta fugacidade de oxig?nio. Utilizando o geoterm?metro do par anfib?lio-plagiocl?sio e o geobar?metro de Al em anfib?lio, foram determinadas temperaturas e press?es em torno de 692-791 ?C e 2,4 e 5,0 kbar para a intrus?o do PBJG, o que ? corroborado por associa??es metam?rficas pr?-existentes nas encaixantes. As caracter?sticas geol?gicas, geoqu?micas e a geocronologia do PBJG demonstram sua natureza p?s-tect?nica ou p?s-colisional, com coloca??o em crosta j? soerguida e relativamente fria, ao final da orog?nese brasiliana nesta por??o da Prov?ncia Tocantins. / The Bom Jardim de Goi?s Pluton (PBJG) is a semi-circular body, located in the central portion of the Tocantins Province, intrusive into orthogneisses and metassupracrustals of the Aren?polis Magmatic Arc. These metasupracrustals present a low to moderate dipping banding or schistosity, have a low to moderate angle of banding / foliation, defined by mica, andalusite and sillimanite and cordierite, which characterize an amphibolite facies metamorphism. This structure is crosscut by the emplacement of the PBJG rocks. The abrupt nature of the contacts and the absence of ductile structures indicate that the intrusion took place in a relatively cold crust. Under petrographic grounds, the pluton consists mainly of monzodiorites, tonalite and granodiorite, following the low to medium-K calk-alkaline alkaline trend. Rocks of the PBJG have hornblende and biotite as the main mafic phases, besides subordinate clinopyroxene, titanite, epidote and opaque. Late dikes of leucogranite contain only mineral biotite as relevant accessory mineral. One U-Pb zircon dating of a monzodiorite yielded an age of 550 ? 12 Ma (MSWD = 1.06). Whole-rock and mineral chemistry suggest that the studied rocks are calc-alkaline, having evolved by fractional crystallization of Ca- and Fe-Mg minerals under high oxygen fugacity. Using the amphibole-plagioclase geothermometer and the Al-in amphibole geobarometer, we calculate temperatures and pressures of, respectively, 692-791 ?C e 2.4-5.0 kbar for the intrusion of the PBJG, which is corroborated by previous metamorphic assemblages in the country rocks. The geological, geochemical and geochronological features of PBJG demonstrate their post-tectonic or post-collisional nature, with emplacement into an already uplifted and relatively cool crust at the end of brasiliano orogeny in this portion of the Tocantins Province.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-26T23:58:51Z No. of bitstreams: 1 BeneditaCleideDeSouzaCampos_DISSERT.pdf: 4403566 bytes, checksum: c3c751a75b003cb890a6499c81c7642f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-31T22:03:44Z (GMT) No. of bitstreams: 1 BeneditaCleideDeSouzaCampos_DISSERT.pdf: 4403566 bytes, checksum: c3c751a75b003cb890a6499c81c7642f (MD5) / Made available in DSpace on 2016-08-31T22:03:44Z (GMT). No. of bitstreams: 1 BeneditaCleideDeSouzaCampos_DISSERT.pdf: 4403566 bytes, checksum: c3c751a75b003cb890a6499c81c7642f (MD5) Previous issue date: 2016-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A qu?mica mineral de granitos, juntamente com revis?o de dados qu?micos de rocha total e petrografia foram utilizados para determinar as condi??es de cristaliza??o e as implica??es na g?nese de granitos C?lcio-alcalinos de alto K Porfir?ticos. Seis corpos gran?ticos foram analisados: Monte das Gameleiras, Barcelona, Acari, Cara?bas, Tour?o e Catol? do Rocha, localizados nos dom?nios Rio Piranhas-Serid? e S?o Jos? de Campestre, NE do Brasil. Os pl?tons s?o representados por monzogranitos, texturalmente possuem f?cies porfir?tica compreendendo fenocristais de K-feldspato com tamanhos entre 5 a 15 cm. K-feldspato, plagiocl?sio e quartzo constituem a parag?nese f?lsica e dominante; enquanto biotita e anfib?lio representam os minerais m?ficos principais; titanita, minerais opacos, allanita, ep?doto, apatita e zirc?o s?o os principais acess?rios. Em rela??o ao ?ndice de Shand o granito Monte das Gameleiras mostra-se mais metaluminoso, enquanto os outros seguem a transi??o metaluminoso a peraluminoso. Em diagramas discriminantes qu?micos estes se apresentam com car?ter transicional (subalcalino). As an?lises de petrografia e qu?mica n?o exp?e as diferen?as dos granitos, por?m os resultados de qu?mica mineral revelam as diferen?as dos mesmos e podem ser divididos em dois grupos: a leste (Monte das Gameleiras, Barcelona e Acari) e a oeste (Cara?bas, Tour?o e Catol? do Rocha). As raz?es Fe/(Fe+Mg) da biotita mostra um aumentam do grupo leste para oeste com valores de 0,48 a 0,64 e 0,66 a 0,92 respectivamente. As raz?es Mg/(Mg+Fe2) do anfib?lio diminui nesse sentido com valores de 0,40 a 0,57 e 0,06 a 0,31. As condi??es de cristaliza??es para os granitos a leste (Monte das Gameleiras, Barcelona e Acari) mostram press?o entre 4.2 kbar a 5.8 kbar, com profundidades que variam de 15,9 km a 20,5 km a uma temperatura entre 710 ?C a 734?C e a oeste (Cara?bas, Tour?o e Catol? do Rocha) com press?es de 5,4 kbar a 7,1 kbar e profundidades que variam de 20 km a 23 km a uma temperatura entre 729 ?C - 753 ?C. Ambas as ?reas, tanto leste como oeste foram gerados a partir de magmas oxidados. As profundidades das intrus?es gran?ticas podem estar relacionadas aos deslocamentos de falhas e ao alto conte?do de ?gua e vol?teis que permitem que o magma de alguns plutons atinja n?veis mais rasos em rela??o aos outros. Os resultados mostram um aumento sistem?tico de temperatura e press?o de cristaliza??o dos pl?tons de leste para oeste sugerindo um espessamento crustal nessa dire??o nos dois dom?nios geol?gicos pesquisados. / The mineral chemistry from granites, chemical of whole rock and review of petrography were used to determine the crystallization conditions and the implications in the genesis of high-K calc-akaline granites that are porphyritics, localizated in the Rio Piranhas-Serid? (RPSD) and S?o Jos? de Campestre Domains (SJCD). Six granitic bodies were analyzed and that for the intrusive granites within the SJCD were named East granites: Monte das Gameleiras, Barcelona. The Acari granite intrudes the area RPSD, however, was called as granite east due to the characteristics of mineral chemistry is similar to east granites. Granites Cara?bas, Tour?o and Catol? do Rocha are intrusive in the RPSD and called west granites. The six bodies are located in the northeast of the Borborema Province, NE Brazil. The plutons are represented by monzogranites wich have porphyritic facies with phenocrysts of K-feldspar with sizes between 5 and 15 cm. The K-feldspar, plagioclase and quartz are the dominant paragenesis; while the biotite and amphibole are the main mafic minerals; and titanite, opaque minerals, allanite, epidote, apatite and zircon are the accessories minerals. The Monte das Gameleiras granite shows metaluminous aluminium saturation index, whereas the others plutons metaluminous to peraluminous. In geochemical diagrams, the granites present with transitional character (subalcalino). The petrographic and geochemical analysis didn't show the differences between the plutons, but according to the mineral chemistry they can be divided into two groups: Monte das Gameleiras, Barcelona and Acari (east) and Cara?bas, Tour?o e Catol? do Rocha (west). The Fe/(Fe + Mg) ratio of biotite shows an increase from east to west group with values from 0.45 to 0.64 and 0.66 to 0.92 respectively, and the Mg / (Mg + Fe2) of amphibole decreases with values from 0.40 to 0.57 and from 0.07 to 0.31. The crystallization parameters of east granites, The crystallization conditions for granites east (Monte das Gameleiras, Barcelona and Acari) show pressure between 3.8 kbar to 5.5 kbar, with depths ranging from 14 km to 21 km at a temperature between 701 ? C to 742?C and west (Cara?bas, Tour?o and Catol? Rock) with pressures to 4.8 kbar to 6.2 kbar and depths ranging from 18 km to 23 km at a temperature between 723 ? C - 776 ? C. Both areas, east and west were generated from magmas oxidized with ?FQM values (-1 a +2.0). The depths of granite intrusion failures may be related to offsets and high water content and volatile that allow the magma some plutons reaches shallower levels in relation to the other. The results show a systematic increase in temperature and crystallization pressure east of plutons west suggesting crustal thickening in that direction. The results show a systematic increase in temperature and crystallization pressure east to west plutons, suggesting crustal thickening in that direction in the two domains studied.