Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil
Autor(a) principal: | |
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Data de Publicação: | 2019 |
Outros Autores: | |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Biblioteca Digital de Teses e Dissertações da UERJ |
Texto Completo: | http://www.bdtd.uerj.br/handle/1/16870 |
Resumo: | The Brazilian marginal basins became prominent worldwide in 2006 when extensive hydrocarbon accumulations were discovered in the Pre-Salt section of Santos Basin. It is characterized by deposits of carbonate rocks deposited during the Aptian. The largest hydrocarbon volume occurs in the Barra Velha Formation (BVF), which is composed mainly by laminites, spherulitites, shrub limestone, intraclastic grainstone and rudstone. Spherulitites has increasingly gained importance due to their expressive occurrence in the BVF (although uncommon in carbonates wordwide), sometimes as important reservoir rock, and for this reason they were studied in detail in this work. Two wells located in different structural contexts in an oil field on Santos Basin were chosen for this study. Variations in texture, morphology, mineralogy, diagenesis and porosity in spherulitic facies were observed through macroscopic description of cores, petrography and the following complementary analysis: X-ray diffratometry, mineralogical map using scanning electron microscopy, punctual chemical analysis using electron microprobe, cathodoluminescence, capillary pressure by mercury injection, and porosity and permeability measurements. Different types of arrangement, morphology, and internal texture of calcitic sherulites were determined. The BVF spherulites present maltese cross extinction pattern or an irregular one, and they can have inclusions (siliciclastic grains, peloids, fossils) or not. Regarding to the size, spherulites were classified from very small to very large. Concerning to the external morphology they were classified as: round and concentric, subrounded or ovoid, polygonal, composite or coalescent, and other morphologies. The spherulites can have different spatial arrangements, from open to very tight. The material between the spherulites most commonly are dolomite, silica and syngenetic Mg-clay minerals. Chemical analyzes in the spherulites showed an increase in Mg content toward the top of the BVF, probably due to the progressive concentration of this element in an increasingly evaporitic environment. A paragenetic sequence of the spherulitites in the BVF was also determine, being the Mg-clay mineral the first phase to form followed by the calcitic spherulite. Dolomite, silica, dawsonite and other mineral phases occurred during eodiagenesis. Dissolution of the Mg-clay mineral between the spherulites during eodiagenesis would be responsible for the generation of secondary porosity. Spherulities very often presents porosity, mainly interspherulite and intercrystalline. Porosity values of most samples are between 5 and 15%, and permeability values are between 0.001 and 500 mD, but can reach values higher than 1000 mD. Three groups of spherulitites were determined based on its petrophysical characteristics: low, intermediate and high reservoir quality. Comparing the two wells, it was noticed that in the one located in the higher structure the spherulitites presents tighter arrangement, bigger spherulites with composite or coalescent morphology, and lack of Mg-clay minerals. Vertical facies stacking show less transitional pattern than the one in the well located in the structural low. Concerning to reservoir quality, the spherulitites in the structural high tend to be better due to the absence of clay minerals |
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Pereira, Egbertohttp://lattes.cnpq.br/1043606043814998Tonietto, Sandra Nélishttp://lattes.cnpq.br/3184082382214512Bergamaschi, Sergiohttp://lattes.cnpq.br/9573016285666019Viana, Samuel Magalhãeshttp://lattes.cnpq.br/9721309033138995http://lattes.cnpq.br/8611883718625460Antônio, Mirella Moreiramoreira_mirella@hotmail.com2021-11-05T19:47:12Z2019-02-28ANTÔNIO, Mirella Moreira. Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil. 2019. 118 f. Dissertação (Mestrado em Geociências) - Faculdade de Geologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2019.http://www.bdtd.uerj.br/handle/1/16870The Brazilian marginal basins became prominent worldwide in 2006 when extensive hydrocarbon accumulations were discovered in the Pre-Salt section of Santos Basin. It is characterized by deposits of carbonate rocks deposited during the Aptian. The largest hydrocarbon volume occurs in the Barra Velha Formation (BVF), which is composed mainly by laminites, spherulitites, shrub limestone, intraclastic grainstone and rudstone. Spherulitites has increasingly gained importance due to their expressive occurrence in the BVF (although uncommon in carbonates wordwide), sometimes as important reservoir rock, and for this reason they were studied in detail in this work. Two wells located in different structural contexts in an oil field on Santos Basin were chosen for this study. Variations in texture, morphology, mineralogy, diagenesis and porosity in spherulitic facies were observed through macroscopic description of cores, petrography and the following complementary analysis: X-ray diffratometry, mineralogical map using scanning electron microscopy, punctual chemical analysis using electron microprobe, cathodoluminescence, capillary pressure by mercury injection, and porosity and permeability measurements. Different types of arrangement, morphology, and internal texture of calcitic sherulites were determined. The BVF spherulites present maltese cross extinction pattern or an irregular one, and they can have inclusions (siliciclastic grains, peloids, fossils) or not. Regarding to the size, spherulites were classified from very small to very large. Concerning to the external morphology they were classified as: round and concentric, subrounded or ovoid, polygonal, composite or coalescent, and other morphologies. The spherulites can have different spatial arrangements, from open to very tight. The material between the spherulites most commonly are dolomite, silica and syngenetic Mg-clay minerals. Chemical analyzes in the spherulites showed an increase in Mg content toward the top of the BVF, probably due to the progressive concentration of this element in an increasingly evaporitic environment. A paragenetic sequence of the spherulitites in the BVF was also determine, being the Mg-clay mineral the first phase to form followed by the calcitic spherulite. Dolomite, silica, dawsonite and other mineral phases occurred during eodiagenesis. Dissolution of the Mg-clay mineral between the spherulites during eodiagenesis would be responsible for the generation of secondary porosity. Spherulities very often presents porosity, mainly interspherulite and intercrystalline. Porosity values of most samples are between 5 and 15%, and permeability values are between 0.001 and 500 mD, but can reach values higher than 1000 mD. Three groups of spherulitites were determined based on its petrophysical characteristics: low, intermediate and high reservoir quality. Comparing the two wells, it was noticed that in the one located in the higher structure the spherulitites presents tighter arrangement, bigger spherulites with composite or coalescent morphology, and lack of Mg-clay minerals. Vertical facies stacking show less transitional pattern than the one in the well located in the structural low. Concerning to reservoir quality, the spherulitites in the structural high tend to be better due to the absence of clay mineralsAs bacias marginais brasileiras passaram a ter destaque mundial a partir de 2006, quando foram descobertas extensas acumulação de hidrocarboneto na Bacia de Santos na seção do Pré-Sal. A seção do Pré-sal é caracterizada por depósitos de rochas carbonáticas de idade Aptiana, no qual os maiores volumes de hidrocarboneto ocorrem na Formação Barra Velha (FBV). A FBV é composta predominantemente por laminitos, calcário arbustiforme e esferulititos. Os esferulititos são o objeto deste trabalho, uma vez que esta fácies tem uma grande ocorrência nos depósitos do Pré-sal, porém é rara ao redor do mundo. Os dois poços escolhidos estão localizados em contextos estratigráficos diferentes. Variação de textura, morfologia, mineralogia, diagênese e porosidade foram observadas nas fáceis esferulitito através da descrição macroscópica de testemunhos e em petrografia foram feitas as seguintes análises: difratometria de raios-x, mapeamento mineralógico automatizado, análises químicas pontuais usando microssonda eletrônica, catodoluminescência, análise de pressão capilar por injeção de mercúrio e medidas de porosidade e permeabilidade. Diferentes tipos de textura do arcabouço, morfologia e textura interna dos esferulitos foram determinados. Os esferulitos da FBV apresentam extinção do tipo cruz de Malta (regular) ou irregular, podendo apresentar inclusões (grãos terrígenos, intraclastos de argilominerais e fósseis) ou não. O tamanho dos esferulitos foi definido entre muito pequeno a muito grande. De acordo com a forma externa eles foram classificados como arredondados ou concêntricos, subarredondados ou ovoides, compostos ou coalescidos e outras formas. Os esferulitittos podem ter textura do arcabouço variando de frouxo a muito fechado. Dolomita (romboédrica e lamelar), sílica (calcedônia e quartzo) e argilomineral magnesiano singenéticos são o material interesferulito mais comuns. A análise química mostrou um aumento da concentração de Mg em direção ao topo da FBV, provavelmente devido ao aumento das condições evaporíticas no ambiente. A sequência paragenética foi determinada a seguinte forma: o argilomineral magnesiano seria a primeira fase, seguido do esferulito. Dolomita, sílica, dawsonita e outras fases minerais ocorreram durante a eodiagênese. A dissolução do argilomineral magnesiano seria o responsável pela geração da porosidade do tipo interesferulito. Os esferulititos comumente apresentam porosidade principalmente dos tipos interesferulito e intercristalino. As maiores concentrações de amostras possuem valores de porosidade entre 5% e 15% e permeabilidade entre 0,001 e 500 mD, podendo chegar até maiores que 1000 mD. Comparando os dois poços, os esferulititos do alto estrutural possuem arcabouço predominantemente fechado e os esferulitos possuem tamanhos maiores e morfologia do tipo composto ou coalescido com ausência de argilomineral magnesiano. A sucessão vertical de fácies mostra que o poço do alto estrutural, possuem intercalações menos transicionais em comparação ao poço do baixo. No que diz respeito a qualidade de reservatório, os esferulititos do alto tendem a ser melhores devido à ausência de argilominerais magnesianosSubmitted by Taciane CTC/C (taciane.silva@uerj.br) on 2021-11-05T19:47:12Z No. of bitstreams: 1 Dissertação - Mirella Moreira Antônio - 2019 - Completa.pdf: 5010779 bytes, checksum: f83c666726687d8398c3b1b3d744b746 (MD5)Made available in DSpace on 2021-11-05T19:47:12Z (GMT). No. of bitstreams: 1 Dissertação - Mirella Moreira Antônio - 2019 - Completa.pdf: 5010779 bytes, checksum: f83c666726687d8398c3b1b3d744b746 (MD5) Previous issue date: 2019-02-28application/pdfporUniversidade do Estado do Rio de JaneiroPrograma de Pós-Graduação em GeociênciasUERJBrasilCentro de Tecnologia e Ciências::Faculdade de GeologiaCarbonatoEsferulititoFormação Barra VelhaCiclo deposicionalSistema porosoGeologia estratigráfica – São Paulo (SP)Petrologia – Barra Velha, Formação (SP)Hidrocarbonetos – São Paulo (SP)Pré-sal – Santos, Bacia de (SP)Carbonatos – Sedimentação e depósitosCarbonateSpherulitesBarra Velha FormationPre-saltDeposicional cyclesPorosityCIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIACaracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, BrasilSedimentological and stratigraphic characterization of the spherulites of the Barra Velha Formation, Santos Basin, Brazilinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisinfo:eu-repo/semantics/openAccessreponame:Biblioteca Digital de Teses e Dissertações da UERJinstname:Universidade do Estado do Rio de Janeiro (UERJ)instacron:UERJORIGINALDissertação - Mirella Moreira Antônio - 2019 - Completa.pdfDissertação - Mirella Moreira Antônio - 2019 - Completa.pdfapplication/pdf5010779http://www.bdtd.uerj.br/bitstream/1/16870/2/Disserta%C3%A7%C3%A3o+-+Mirella+Moreira+Ant%C3%B4nio+-+2019+-+Completa.pdff83c666726687d8398c3b1b3d744b746MD52LICENSElicense.txtlicense.txttext/plain; charset=utf-82123http://www.bdtd.uerj.br/bitstream/1/16870/1/license.txte5502652da718045d7fcd832b79fca29MD511/168702024-02-27 15:43:48.957oai:www.bdtd.uerj.br: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Biblioteca Digital de Teses e Dissertaçõeshttp://www.bdtd.uerj.br/PUBhttps://www.bdtd.uerj.br:8443/oai/requestbdtd.suporte@uerj.bropendoar:29032024-02-27T18:43:48Biblioteca Digital de Teses e Dissertações da UERJ - Universidade do Estado do Rio de Janeiro (UERJ)false |
dc.title.por.fl_str_mv |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
dc.title.alternative.eng.fl_str_mv |
Sedimentological and stratigraphic characterization of the spherulites of the Barra Velha Formation, Santos Basin, Brazil |
title |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
spellingShingle |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil Antônio, Mirella Moreira Carbonato Esferulitito Formação Barra Velha Ciclo deposicional Sistema poroso Geologia estratigráfica – São Paulo (SP) Petrologia – Barra Velha, Formação (SP) Hidrocarbonetos – São Paulo (SP) Pré-sal – Santos, Bacia de (SP) Carbonatos – Sedimentação e depósitos Carbonate Spherulites Barra Velha Formation Pre-salt Deposicional cycles Porosity CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA |
title_short |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
title_full |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
title_fullStr |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
title_full_unstemmed |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
title_sort |
Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil |
author |
Antônio, Mirella Moreira |
author_facet |
Antônio, Mirella Moreira moreira_mirella@hotmail.com |
author_role |
author |
author2 |
moreira_mirella@hotmail.com |
author2_role |
author |
dc.contributor.advisor1.fl_str_mv |
Pereira, Egberto |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/1043606043814998 |
dc.contributor.advisor-co1.fl_str_mv |
Tonietto, Sandra Nélis |
dc.contributor.advisor-co1Lattes.fl_str_mv |
http://lattes.cnpq.br/3184082382214512 |
dc.contributor.referee1.fl_str_mv |
Bergamaschi, Sergio |
dc.contributor.referee1Lattes.fl_str_mv |
http://lattes.cnpq.br/9573016285666019 |
dc.contributor.referee2.fl_str_mv |
Viana, Samuel Magalhães |
dc.contributor.referee2Lattes.fl_str_mv |
http://lattes.cnpq.br/9721309033138995 |
dc.contributor.authorLattes.fl_str_mv |
http://lattes.cnpq.br/8611883718625460 |
dc.contributor.author.fl_str_mv |
Antônio, Mirella Moreira moreira_mirella@hotmail.com |
contributor_str_mv |
Pereira, Egberto Tonietto, Sandra Nélis Bergamaschi, Sergio Viana, Samuel Magalhães |
dc.subject.por.fl_str_mv |
Carbonato Esferulitito Formação Barra Velha Ciclo deposicional Sistema poroso Geologia estratigráfica – São Paulo (SP) Petrologia – Barra Velha, Formação (SP) Hidrocarbonetos – São Paulo (SP) Pré-sal – Santos, Bacia de (SP) Carbonatos – Sedimentação e depósitos Carbonate Spherulites Barra Velha Formation Pre-salt Deposicional cycles Porosity |
topic |
Carbonato Esferulitito Formação Barra Velha Ciclo deposicional Sistema poroso Geologia estratigráfica – São Paulo (SP) Petrologia – Barra Velha, Formação (SP) Hidrocarbonetos – São Paulo (SP) Pré-sal – Santos, Bacia de (SP) Carbonatos – Sedimentação e depósitos Carbonate Spherulites Barra Velha Formation Pre-salt Deposicional cycles Porosity CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA |
dc.subject.cnpq.fl_str_mv |
CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA |
description |
The Brazilian marginal basins became prominent worldwide in 2006 when extensive hydrocarbon accumulations were discovered in the Pre-Salt section of Santos Basin. It is characterized by deposits of carbonate rocks deposited during the Aptian. The largest hydrocarbon volume occurs in the Barra Velha Formation (BVF), which is composed mainly by laminites, spherulitites, shrub limestone, intraclastic grainstone and rudstone. Spherulitites has increasingly gained importance due to their expressive occurrence in the BVF (although uncommon in carbonates wordwide), sometimes as important reservoir rock, and for this reason they were studied in detail in this work. Two wells located in different structural contexts in an oil field on Santos Basin were chosen for this study. Variations in texture, morphology, mineralogy, diagenesis and porosity in spherulitic facies were observed through macroscopic description of cores, petrography and the following complementary analysis: X-ray diffratometry, mineralogical map using scanning electron microscopy, punctual chemical analysis using electron microprobe, cathodoluminescence, capillary pressure by mercury injection, and porosity and permeability measurements. Different types of arrangement, morphology, and internal texture of calcitic sherulites were determined. The BVF spherulites present maltese cross extinction pattern or an irregular one, and they can have inclusions (siliciclastic grains, peloids, fossils) or not. Regarding to the size, spherulites were classified from very small to very large. Concerning to the external morphology they were classified as: round and concentric, subrounded or ovoid, polygonal, composite or coalescent, and other morphologies. The spherulites can have different spatial arrangements, from open to very tight. The material between the spherulites most commonly are dolomite, silica and syngenetic Mg-clay minerals. Chemical analyzes in the spherulites showed an increase in Mg content toward the top of the BVF, probably due to the progressive concentration of this element in an increasingly evaporitic environment. A paragenetic sequence of the spherulitites in the BVF was also determine, being the Mg-clay mineral the first phase to form followed by the calcitic spherulite. Dolomite, silica, dawsonite and other mineral phases occurred during eodiagenesis. Dissolution of the Mg-clay mineral between the spherulites during eodiagenesis would be responsible for the generation of secondary porosity. Spherulities very often presents porosity, mainly interspherulite and intercrystalline. Porosity values of most samples are between 5 and 15%, and permeability values are between 0.001 and 500 mD, but can reach values higher than 1000 mD. Three groups of spherulitites were determined based on its petrophysical characteristics: low, intermediate and high reservoir quality. Comparing the two wells, it was noticed that in the one located in the higher structure the spherulitites presents tighter arrangement, bigger spherulites with composite or coalescent morphology, and lack of Mg-clay minerals. Vertical facies stacking show less transitional pattern than the one in the well located in the structural low. Concerning to reservoir quality, the spherulitites in the structural high tend to be better due to the absence of clay minerals |
publishDate |
2019 |
dc.date.issued.fl_str_mv |
2019-02-28 |
dc.date.accessioned.fl_str_mv |
2021-11-05T19:47:12Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
ANTÔNIO, Mirella Moreira. Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil. 2019. 118 f. Dissertação (Mestrado em Geociências) - Faculdade de Geologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2019. |
dc.identifier.uri.fl_str_mv |
http://www.bdtd.uerj.br/handle/1/16870 |
identifier_str_mv |
ANTÔNIO, Mirella Moreira. Caracterização sedimentológica e estratigráfica dos esferulitos da Formação Barra Velha da Bacia de Santos, Brasil. 2019. 118 f. Dissertação (Mestrado em Geociências) - Faculdade de Geologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2019. |
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http://www.bdtd.uerj.br/handle/1/16870 |
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por |
language |
por |
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info:eu-repo/semantics/openAccess |
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openAccess |
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application/pdf |
dc.publisher.none.fl_str_mv |
Universidade do Estado do Rio de Janeiro |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Geociências |
dc.publisher.initials.fl_str_mv |
UERJ |
dc.publisher.country.fl_str_mv |
Brasil |
dc.publisher.department.fl_str_mv |
Centro de Tecnologia e Ciências::Faculdade de Geologia |
publisher.none.fl_str_mv |
Universidade do Estado do Rio de Janeiro |
dc.source.none.fl_str_mv |
reponame:Biblioteca Digital de Teses e Dissertações da UERJ instname:Universidade do Estado do Rio de Janeiro (UERJ) instacron:UERJ |
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Universidade do Estado do Rio de Janeiro (UERJ) |
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UERJ |
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UERJ |
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Biblioteca Digital de Teses e Dissertações da UERJ |
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Biblioteca Digital de Teses e Dissertações da UERJ |
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http://www.bdtd.uerj.br/bitstream/1/16870/2/Disserta%C3%A7%C3%A3o+-+Mirella+Moreira+Ant%C3%B4nio+-+2019+-+Completa.pdf http://www.bdtd.uerj.br/bitstream/1/16870/1/license.txt |
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MD5 MD5 |
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Biblioteca Digital de Teses e Dissertações da UERJ - Universidade do Estado do Rio de Janeiro (UERJ) |
repository.mail.fl_str_mv |
bdtd.suporte@uerj.br |
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1811728701007593472 |