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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evolução sedimentológica e paleogeográfica do sistema de riftes do Espinhaço Meridional

Santos, Marcelo Nascimento dos January 2011 (has links)
Dois eventos distintos de rifteamento separados por um gap de 500 Ma foram reconhecidos no Espinhaço Meridional, conduzindo a novas interpretações sobre a evolução tectono-sedimentar da região. Mapeamento em detalhe (na escala 1:3,000) e levantamento e correlação de vinte e seis seções estratigráficas (na escala 1/100) foram realizados em duas áreas menos deformadas. Baseado nos sistemas deposicionais identificados, foi possível determinar os tratos de sistema tectônicos envolvidos na evolução do Sistema de Riftes do Espinhaço, os quais refletem o estágio de evolução de cada bacia. As discordâncias observadas permitiram a proposição de uma nova classificação estratigráfica, a aloestratigrafia, cuja principal vantagem reside no fato de ser essencialmente descritiva. Na Bacia Espinhaço inferior (sensu Chemale et al., 2010), foram identificados: rift initiation systems tract e o early rift climax systems tract, compreendendo respectivamente os sintemas Bandeirinha (limitado por uma desconformidade e por uma discordância angular) e São João da Chapada (limitado por duas discordâncias angulares). O nível D, denominado informalmente, composto por pelitos, foi incorporado ao Sintema São João da Chapada. Na Bacia Espinhaço superior foram identificados: o early rift climax systems tract e o immediate post-rift systems tract, compreendendo os sintemas Sopa-Brumadinho (limitado por uma discordância angular e uma paraconformidade), Galho do Miguel (limitado por duas paraconformidades) e Conselheiro Mata (limitado por uma paraconformidade e por uma discordância angular). / Two distinct rifting events separated by a gap of 500 Ma have been recognized in the southern Espinhaço mountains, implying a new interpretation of the tectono-sedimentary evolution of the region. Detailed mapping (at a scale of 1:3,000), was conducted with even finer detail in twenty-six sections (at a scale of 1:100) in two less-deformed areas and their lateral correlations. Based on the identified depositional systems, it was possible to determine the tectonic system tracts involved in the evolution of the Southern Espinhaço Rift System that reflect the stage of evolution of each basin. The unconformities observed allowed the proposal of a new stratigraphic classification, allostratigraphy, whose main advantage is its essentially descriptive nature. In the lower Espinhaço Basin (sensu Chemale et al., 2010), the rift initiation system tract and the early rift climax system tract that comprise the Bandeirinha Synthem (limited by a disconformity and an angular unconformity) and the São João da Chapada Synthem (limited by two angular unconformities) were identified. The informal level D, composed of pelites, was incorporated into the São João da Chapada Synthem. In the upper Espinhaço Basin (sensu Chemale et al., 2010), the early rift climax systems tract and the immediate post-rift systems tract that comprise the Sopa-Brumadinho (limited by an angular unconformity and a paraconformity), Galho do Miguel (limited by two paraconformities) and Conselheiro Mata (limited by a paraconformity and an angular unconformity) synthems were identified.
2

Integrated approach to solving reservoir problems and evaluations using sequence stratigraphy, geological structures and diagenesis in Orange Basin, South Africa

Solomon Adeniyi Adekola January 2010 (has links)
<p>Sandstone and shale samples were selected within the systems tracts for laboratory analyses. The sidewall and core samples were subjected to petrographic thin section analysis, mineralogical analyses which include x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and stable carbon and oxygen isotopes geochemistry to determine the diagenetic alteration at deposition and post deposition in the basin. The shale samples were subjected to Rock-Eval pyrolysis and accelerated solvent extraction (ASE) prior to gas chromatographic (GC) and gas chromatographic-mass spectrometric (GC-MS) analyses of the rock extracts, in order to determine the provenance, type and thermal maturity of organic matter present in sediments of the Orange Basin. The results revealed a complex diagenetic history of sandstones in this basin, which includes compaction, cementation/micritization, dissolution, silicification/overgrowth of quartz, and fracturing. The Eh-pH shows that the cements in the area of the basin under investigation were precipitated under weak acidic and slightly alkaline conditions. The &delta / 18O isotope values range from -1.648 to 10.054 %, -1.574 to 13.134 %, and -2.644 to 16.180 % in the LST, TST, and HST, respectively. While &delta / 13C isotope values range from -25.667 to -12.44 %, -27.862 to -6.954% and -27.407 to -19.935 % in the LST, TST, and HST, respectively. The plot of &delta / 18O versus &delta / 13C shows that the sediments were deposited in shallow marine temperate conditions.</p>
3

Integrated approach to solving reservoir problems and evaluations using sequence stratigraphy, geological structures and diagenesis in Orange Basin, South Africa

Solomon Adeniyi Adekola January 2010 (has links)
<p>Sandstone and shale samples were selected within the systems tracts for laboratory analyses. The sidewall and core samples were subjected to petrographic thin section analysis, mineralogical analyses which include x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and stable carbon and oxygen isotopes geochemistry to determine the diagenetic alteration at deposition and post deposition in the basin. The shale samples were subjected to Rock-Eval pyrolysis and accelerated solvent extraction (ASE) prior to gas chromatographic (GC) and gas chromatographic-mass spectrometric (GC-MS) analyses of the rock extracts, in order to determine the provenance, type and thermal maturity of organic matter present in sediments of the Orange Basin. The results revealed a complex diagenetic history of sandstones in this basin, which includes compaction, cementation/micritization, dissolution, silicification/overgrowth of quartz, and fracturing. The Eh-pH shows that the cements in the area of the basin under investigation were precipitated under weak acidic and slightly alkaline conditions. The &delta / 18O isotope values range from -1.648 to 10.054 %, -1.574 to 13.134 %, and -2.644 to 16.180 % in the LST, TST, and HST, respectively. While &delta / 13C isotope values range from -25.667 to -12.44 %, -27.862 to -6.954% and -27.407 to -19.935 % in the LST, TST, and HST, respectively. The plot of &delta / 18O versus &delta / 13C shows that the sediments were deposited in shallow marine temperate conditions.</p>
4

Evolução sedimentológica e paleogeográfica do sistema de riftes do Espinhaço Meridional

Santos, Marcelo Nascimento dos January 2011 (has links)
Dois eventos distintos de rifteamento separados por um gap de 500 Ma foram reconhecidos no Espinhaço Meridional, conduzindo a novas interpretações sobre a evolução tectono-sedimentar da região. Mapeamento em detalhe (na escala 1:3,000) e levantamento e correlação de vinte e seis seções estratigráficas (na escala 1/100) foram realizados em duas áreas menos deformadas. Baseado nos sistemas deposicionais identificados, foi possível determinar os tratos de sistema tectônicos envolvidos na evolução do Sistema de Riftes do Espinhaço, os quais refletem o estágio de evolução de cada bacia. As discordâncias observadas permitiram a proposição de uma nova classificação estratigráfica, a aloestratigrafia, cuja principal vantagem reside no fato de ser essencialmente descritiva. Na Bacia Espinhaço inferior (sensu Chemale et al., 2010), foram identificados: rift initiation systems tract e o early rift climax systems tract, compreendendo respectivamente os sintemas Bandeirinha (limitado por uma desconformidade e por uma discordância angular) e São João da Chapada (limitado por duas discordâncias angulares). O nível D, denominado informalmente, composto por pelitos, foi incorporado ao Sintema São João da Chapada. Na Bacia Espinhaço superior foram identificados: o early rift climax systems tract e o immediate post-rift systems tract, compreendendo os sintemas Sopa-Brumadinho (limitado por uma discordância angular e uma paraconformidade), Galho do Miguel (limitado por duas paraconformidades) e Conselheiro Mata (limitado por uma paraconformidade e por uma discordância angular). / Two distinct rifting events separated by a gap of 500 Ma have been recognized in the southern Espinhaço mountains, implying a new interpretation of the tectono-sedimentary evolution of the region. Detailed mapping (at a scale of 1:3,000), was conducted with even finer detail in twenty-six sections (at a scale of 1:100) in two less-deformed areas and their lateral correlations. Based on the identified depositional systems, it was possible to determine the tectonic system tracts involved in the evolution of the Southern Espinhaço Rift System that reflect the stage of evolution of each basin. The unconformities observed allowed the proposal of a new stratigraphic classification, allostratigraphy, whose main advantage is its essentially descriptive nature. In the lower Espinhaço Basin (sensu Chemale et al., 2010), the rift initiation system tract and the early rift climax system tract that comprise the Bandeirinha Synthem (limited by a disconformity and an angular unconformity) and the São João da Chapada Synthem (limited by two angular unconformities) were identified. The informal level D, composed of pelites, was incorporated into the São João da Chapada Synthem. In the upper Espinhaço Basin (sensu Chemale et al., 2010), the early rift climax systems tract and the immediate post-rift systems tract that comprise the Sopa-Brumadinho (limited by an angular unconformity and a paraconformity), Galho do Miguel (limited by two paraconformities) and Conselheiro Mata (limited by a paraconformity and an angular unconformity) synthems were identified.
5

Evolução sedimentológica e paleogeográfica do sistema de riftes do Espinhaço Meridional

Santos, Marcelo Nascimento dos January 2011 (has links)
Dois eventos distintos de rifteamento separados por um gap de 500 Ma foram reconhecidos no Espinhaço Meridional, conduzindo a novas interpretações sobre a evolução tectono-sedimentar da região. Mapeamento em detalhe (na escala 1:3,000) e levantamento e correlação de vinte e seis seções estratigráficas (na escala 1/100) foram realizados em duas áreas menos deformadas. Baseado nos sistemas deposicionais identificados, foi possível determinar os tratos de sistema tectônicos envolvidos na evolução do Sistema de Riftes do Espinhaço, os quais refletem o estágio de evolução de cada bacia. As discordâncias observadas permitiram a proposição de uma nova classificação estratigráfica, a aloestratigrafia, cuja principal vantagem reside no fato de ser essencialmente descritiva. Na Bacia Espinhaço inferior (sensu Chemale et al., 2010), foram identificados: rift initiation systems tract e o early rift climax systems tract, compreendendo respectivamente os sintemas Bandeirinha (limitado por uma desconformidade e por uma discordância angular) e São João da Chapada (limitado por duas discordâncias angulares). O nível D, denominado informalmente, composto por pelitos, foi incorporado ao Sintema São João da Chapada. Na Bacia Espinhaço superior foram identificados: o early rift climax systems tract e o immediate post-rift systems tract, compreendendo os sintemas Sopa-Brumadinho (limitado por uma discordância angular e uma paraconformidade), Galho do Miguel (limitado por duas paraconformidades) e Conselheiro Mata (limitado por uma paraconformidade e por uma discordância angular). / Two distinct rifting events separated by a gap of 500 Ma have been recognized in the southern Espinhaço mountains, implying a new interpretation of the tectono-sedimentary evolution of the region. Detailed mapping (at a scale of 1:3,000), was conducted with even finer detail in twenty-six sections (at a scale of 1:100) in two less-deformed areas and their lateral correlations. Based on the identified depositional systems, it was possible to determine the tectonic system tracts involved in the evolution of the Southern Espinhaço Rift System that reflect the stage of evolution of each basin. The unconformities observed allowed the proposal of a new stratigraphic classification, allostratigraphy, whose main advantage is its essentially descriptive nature. In the lower Espinhaço Basin (sensu Chemale et al., 2010), the rift initiation system tract and the early rift climax system tract that comprise the Bandeirinha Synthem (limited by a disconformity and an angular unconformity) and the São João da Chapada Synthem (limited by two angular unconformities) were identified. The informal level D, composed of pelites, was incorporated into the São João da Chapada Synthem. In the upper Espinhaço Basin (sensu Chemale et al., 2010), the early rift climax systems tract and the immediate post-rift systems tract that comprise the Sopa-Brumadinho (limited by an angular unconformity and a paraconformity), Galho do Miguel (limited by two paraconformities) and Conselheiro Mata (limited by a paraconformity and an angular unconformity) synthems were identified.
6

Integrated approach to solving reservoir problems and evaluations using sequence stratigraphy, geological structures and diagenesis in Orange Basin, South Africa

Adekola, Solomon Adeniyi January 2010 (has links)
Philosophiae Doctor - PhD / Sandstone and shale samples were selected within the systems tracts for laboratory analyses. The sidewall and core samples were subjected to petrographic thin section analysis, mineralogical analyses which include x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and stable carbon and oxygen isotopes geochemistry to determine the diagenetic alteration at deposition and post deposition in the basin. The shale samples were subjected to Rock-Eval pyrolysis and accelerated solvent extraction (ASE) prior to gas chromatographic (GC) and gas chromatographic-mass spectrometric (GC-MS) analyses of the rock extracts, in order to determine the provenance, type and thermal maturity of organic matter present in sediments of the Orange Basin. The results revealed a complex diagenetic history of sandstones in this basin, which includes compaction, cementation/micritization, dissolution, silicification/overgrowth of quartz, and fracturing. The Eh-pH shows that the cements in the area of the basin under investigation were precipitated under weak acidic and slightly alkaline conditions. The δ18O isotope values range from -1.648 to 10.054 %, -1.574 to 13.134 %, and -2.644 to 16.180 % in the LST, TST, and HST, respectively. While δ13C isotope values range from -25.667 to -12.44 %, -27.862 to -6.954% and -27.407 to -19.935 % in the LST, TST, and HST, respectively. The plot of δ18O versus δ13C shows that the sediments were deposited in shallow marine temperate conditions. / South Africa
7

Estratigrafia de seqüências do Grupo Itararé (Neocarbonifero-Eopermiano) na região de Rio Negro (PR) - Mafra (SC) /

Weinschütz, Luiz Carlos. January 2006 (has links)
Orientador: Joel Carneiro de Castro / Banca: Maria Rita Caetano Chang / Banca: Antonio Roberto Saad / Banca: Paulo Roberto dos Santos / Banca: Oscar Rösler / Resumo: O Grupo Itararé consiste de três grandes ciclos de afinamento ascendente, aos quais foi dado o status de Formação, nomeadas Lagoa Azul, Campo Mourão e Taciba. Essa é uma das bases para estabelecer a Estratigrafia de Seqüências do grupo; a outra é fornecida pelos ciclos climáticos do Quaternário, com os estágios glacial, deglacial e interglacial. A área de Rio Negro-Mafra apresenta uma excelente testemunhagem de poços que, junto a bons afloramentos, possibilita a construção de extensos perfis verticais de fácies; as fácies e ciclos de fácies formam a base para os Sistemas Deposicionais, cuja disposição espacial proporciona a construção das Seqüências. Cinco sistemas são identificados, Arenito, Diamictito, Folhelho, Varvito-Diamictito e Deglaciação, este formado por conglomerado, arenito, diamictito, varvito e folhelho. A estrutura de um Sistema de Deglaciação é a mesma do grande ciclo proposto para a estratigrafia do Grupo Itararé, exceto a mudança do varvito acima para ritmito da proposta litocronoestratigráfica. Foram identificadas cinco seqüências no Grupo Itararé. A seqüência Campo do Tenente, formada por dois espessos sistemas de varvitodiamictito, representando sistema glacicontinental correspondente a trato de mar alto. As seqüências Campo Mourão-I e II, iniciam com espessos sistemas Arenito de trato de mar baixo, seguindo-se sistemas Varvito-Diamictito (só para CM-I), de Deglaciação (trato transgressivo) e Folhelho marinho de mar alto (Siltito Mafra em CM-I, Folhelho Lontras em CM-II). As seqüências Taciba-I e II são mais complexas. TC-I começa com sistema Diamictito espesso, glacimarinho associado a mar alto?, seguido de sistema de Deglaciação. TC-II tem sistema Arenito canalizado de mar baixo, seguido de sistema de Deglaciação transgressiva e sistema Folhelho de mar alto. / Abstract: The Itararé Group consists of three major fining-upward cycles, also considered as Formations: Lagoa Azul, Campo Mourão and Taciba. This is one of basis to establish the Sequence Stratigraphy for the group; the other one comes from the Quaternary model, where one can recognize three stages of a climatic cycle: glacial, deglacial, interglacial. The Rio Negro-Mafra area presents excellent cored wells and outcrops which allow to build extensive vertical facies logs; facies and facies cycle are the basis for Depositional Systems, whose spatial distribution allows to build Depositional Sequences. Five Systems are identified: Sandstone, Diamictite, Shale, Varvite- Diamictite and Deglaciation. The latter is formed by conglomerate, sandstone, diamictito, varvite and shale. The structure of the Deglaciation System is the same of one major cycle/Formation of Itararé Group, except for the varvite component, or rhythmite in the major cycle. Five sequences are recognized. The Campo do Tenente sequence is formed by two thick varvite-diamictite systems, from a glacicontinental system attributed to a highstand tract (the Campo do Tenente is a marginal equivalent of the marine Lagoa Azul/Roncador Bed). The Campo Mourão sequences (CM-I and CMII) begin with thick Sandstone systems from a lowstand tract; it follows Varvite- Diamictite (only for CM-I), Deglaciation and marine Shale systems, respectively from transgressive and highstand tracts (the CM-2 marine system is the thick Lontras Shale). Taciba Formation sequences TB-I and TB-II are more complex. TB-I starts with a thick, glaciomarine Diamictite system (highstand tract?), and is followed by Deglaciation system. TC-II starts with a channelized, lowstand Sandstone system, estuarine, deltaic and turbidite in origin; it follows the Deglatiation and marine Shale systems, from transgressive and highstand tracts. / Doutor
8

Sequence stratigraphic characterisation of petroleum reservoirs in Block 11b/12b of the Southern Outeniqua Basin

Nformi, Emmanuel Nfor January 2011 (has links)
<p>The main purpose of this study was to identify and characterize the various sand prone depositional facies in the deepwater Southern Outeniqua Basin which generally tend to form during&nbsp / lowstand (marine regression) conditions producing progradational facies. It made use of sequence stratigraphy and turbidite facies models to predict the probable location of deepwater&nbsp / reservoirs in the undrilled Southern Outeniqua Basin using data from basin margin Pletmos Basin and the deepwater Southern Outeniqua Basin. Basin margin depositional packages were&nbsp / correlated in time and space with deepwater packages. It was an attempt at bridging the gap between process-related studies of sedimentary rocks and the more traditional economic geology&nbsp / f commercial deposits of petroleum using prevailing state-of-the-art in basin analysis. It enabled the most realistic reconstructions of genetic stratigraphy and offered the greatest&nbsp / application in exploration. Sequence stratigraphic analysis and interpretation of seismics, well logs, cores and biostratigraphic data was carried out providing a chronostratigraphic framework of the study area within which seismic facies analysis done. Nine (9) seismic lines that span the shallow/basin margin Pletmos basin into the undrilled deepwater Southern Outeniqua basin were analysed and interpreted and the relevant seismic geometries were captured. Four (4) turbidite depositional elements were identified from the seismic lines: channel, overbank deposits,&nbsp / haotic deposits and basin plain (basin floor fan) deposits. These were identified from the relevant seismic geometries (geometric attributes) observed on the 2D seismic lines. Thinning attributes, unconformity attributes and seismic facies attributes were observed from the seismic lines. This was preceded by basic structural analyses and interpretation of the&nbsp / seismic lines. according to the structural analysis and interpretation, deposition trended NW-SE and NNW-SSE as we go deepwater into the Southern Outeniqua basin. Well logs from six (6)&nbsp / of the interpreted wells indicated depositional channel fill as well as basin floor fans. This was identified in well Ga-V1 and Ga-S1 respectively. A bell and crescent shape gamma ray log&nbsp / signature was observed in well Ga-V1 indicating a fining up sequence as the channel was abandoned while an isolated massive mound-shape gamma ray log signature was observed in&nbsp / Ga-S1 indicating basin plain well-sorted sands. Core analyses and interpretation from two southern-most wells revealed three (3) facies which were derived based on Walker&lsquo / s 1978, turbidite&nbsp / facies. The observed facies were: sandstone, sand/shale and shale facies. Sequence stratigraphic characterisation of petroleum reservoirs in block 11b/12b of the Southern Outeniqua&nbsp / Basin. Cores of well Ga-V1 displayed fine-grained alternations of thin sandstone beds and shales belonging to the thin-bedded turbidite facies. This is typical of levees of the upper fan channel but&nbsp / could easily be confused with similar facies on the basin plain. According to Walker, 1978 such facies form under conditions of active fan progradation. Ga-S1 cores displayed not only classic&nbsp / turbidite facies where there was alternating sand and shale sections but showed thick uninterrupted sections of clean sands. This is typical of basin plain deposits. Only one well had&nbsp / biostratigraphic data though being very limited in content. This data revealed particular depth sections and stratigraphic sections as having medium to fast depositional rates. Such rates are&nbsp / characteristic of turbidite deposition from turbidity currents. This study as well as a complementary study by Carvajal et al., 2009 revealed that the Southern Outeniqua basin is a sand-prone&nbsp / basin with many progradational sequences in which tectonics and sediment supply rate have been significant factors (amongst others such as sea level change) in the formation of these&nbsp / deepwater sequences. In conclusion, the Southern Outeniqua basin was hereby seen as having a viable and unexplored petroleum system existing in this sand prone untested world class.</p>
9

Sequence stratigraphic characterisation of petroleum reservoirs in Block 11b/12b of the Southern Outeniqua Basin

Nformi, Emmanuel Nfor January 2011 (has links)
<p>The main purpose of this study was to identify and characterize the various sand prone depositional facies in the deepwater Southern Outeniqua Basin which generally tend to form during&nbsp / lowstand (marine regression) conditions producing progradational facies. It made use of sequence stratigraphy and turbidite facies models to predict the probable location of deepwater&nbsp / reservoirs in the undrilled Southern Outeniqua Basin using data from basin margin Pletmos Basin and the deepwater Southern Outeniqua Basin. Basin margin depositional packages were&nbsp / correlated in time and space with deepwater packages. It was an attempt at bridging the gap between process-related studies of sedimentary rocks and the more traditional economic geology&nbsp / f commercial deposits of petroleum using prevailing state-of-the-art in basin analysis. It enabled the most realistic reconstructions of genetic stratigraphy and offered the greatest&nbsp / application in exploration. Sequence stratigraphic analysis and interpretation of seismics, well logs, cores and biostratigraphic data was carried out providing a chronostratigraphic framework of the study area within which seismic facies analysis done. Nine (9) seismic lines that span the shallow/basin margin Pletmos basin into the undrilled deepwater Southern Outeniqua basin were analysed and interpreted and the relevant seismic geometries were captured. Four (4) turbidite depositional elements were identified from the seismic lines: channel, overbank deposits,&nbsp / haotic deposits and basin plain (basin floor fan) deposits. These were identified from the relevant seismic geometries (geometric attributes) observed on the 2D seismic lines. Thinning attributes, unconformity attributes and seismic facies attributes were observed from the seismic lines. This was preceded by basic structural analyses and interpretation of the&nbsp / seismic lines. according to the structural analysis and interpretation, deposition trended NW-SE and NNW-SSE as we go deepwater into the Southern Outeniqua basin. Well logs from six (6)&nbsp / of the interpreted wells indicated depositional channel fill as well as basin floor fans. This was identified in well Ga-V1 and Ga-S1 respectively. A bell and crescent shape gamma ray log&nbsp / signature was observed in well Ga-V1 indicating a fining up sequence as the channel was abandoned while an isolated massive mound-shape gamma ray log signature was observed in&nbsp / Ga-S1 indicating basin plain well-sorted sands. Core analyses and interpretation from two southern-most wells revealed three (3) facies which were derived based on Walker&lsquo / s 1978, turbidite&nbsp / facies. The observed facies were: sandstone, sand/shale and shale facies. Sequence stratigraphic characterisation of petroleum reservoirs in block 11b/12b of the Southern Outeniqua&nbsp / Basin. Cores of well Ga-V1 displayed fine-grained alternations of thin sandstone beds and shales belonging to the thin-bedded turbidite facies. This is typical of levees of the upper fan channel but&nbsp / could easily be confused with similar facies on the basin plain. According to Walker, 1978 such facies form under conditions of active fan progradation. Ga-S1 cores displayed not only classic&nbsp / turbidite facies where there was alternating sand and shale sections but showed thick uninterrupted sections of clean sands. This is typical of basin plain deposits. Only one well had&nbsp / biostratigraphic data though being very limited in content. This data revealed particular depth sections and stratigraphic sections as having medium to fast depositional rates. Such rates are&nbsp / characteristic of turbidite deposition from turbidity currents. This study as well as a complementary study by Carvajal et al., 2009 revealed that the Southern Outeniqua basin is a sand-prone&nbsp / basin with many progradational sequences in which tectonics and sediment supply rate have been significant factors (amongst others such as sea level change) in the formation of these&nbsp / deepwater sequences. In conclusion, the Southern Outeniqua basin was hereby seen as having a viable and unexplored petroleum system existing in this sand prone untested world class.</p>
10

Estratigrafia de seqüências do Grupo Itararé (Neocarbonifero-Eopermiano) na região de Rio Negro (PR) - Mafra (SC)

Weinschütz, Luiz Carlos [UNESP] 30 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-30Bitstream added on 2014-06-13T19:42:54Z : No. of bitstreams: 1 weinschutz_lc_dr_rcla.pdf: 1742525 bytes, checksum: 5b9c5ed9e9f54d4ef0daafc46b0439a4 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O Grupo Itararé consiste de três grandes ciclos de afinamento ascendente, aos quais foi dado o status de Formação, nomeadas Lagoa Azul, Campo Mourão e Taciba. Essa é uma das bases para estabelecer a Estratigrafia de Seqüências do grupo; a outra é fornecida pelos ciclos climáticos do Quaternário, com os estágios glacial, deglacial e interglacial. A área de Rio Negro-Mafra apresenta uma excelente testemunhagem de poços que, junto a bons afloramentos, possibilita a construção de extensos perfis verticais de fácies; as fácies e ciclos de fácies formam a base para os Sistemas Deposicionais, cuja disposição espacial proporciona a construção das Seqüências. Cinco sistemas são identificados, Arenito, Diamictito, Folhelho, Varvito-Diamictito e Deglaciação, este formado por conglomerado, arenito, diamictito, varvito e folhelho. A estrutura de um Sistema de Deglaciação é a mesma do grande ciclo proposto para a estratigrafia do Grupo Itararé, exceto a mudança do varvito acima para ritmito da proposta litocronoestratigráfica. Foram identificadas cinco seqüências no Grupo Itararé. A seqüência Campo do Tenente, formada por dois espessos sistemas de varvitodiamictito, representando sistema glacicontinental correspondente a trato de mar alto. As seqüências Campo Mourão-I e II, iniciam com espessos sistemas Arenito de trato de mar baixo, seguindo-se sistemas Varvito-Diamictito (só para CM-I), de Deglaciação (trato transgressivo) e Folhelho marinho de mar alto (Siltito Mafra em CM-I, Folhelho Lontras em CM-II). As seqüências Taciba-I e II são mais complexas. TC-I começa com sistema Diamictito espesso, glacimarinho associado a mar alto?, seguido de sistema de Deglaciação. TC-II tem sistema Arenito canalizado de mar baixo, seguido de sistema de Deglaciação transgressiva e sistema Folhelho de mar alto. / The Itararé Group consists of three major fining-upward cycles, also considered as Formations: Lagoa Azul, Campo Mourão and Taciba. This is one of basis to establish the Sequence Stratigraphy for the group; the other one comes from the Quaternary model, where one can recognize three stages of a climatic cycle: glacial, deglacial, interglacial. The Rio Negro-Mafra area presents excellent cored wells and outcrops which allow to build extensive vertical facies logs; facies and facies cycle are the basis for Depositional Systems, whose spatial distribution allows to build Depositional Sequences. Five Systems are identified: Sandstone, Diamictite, Shale, Varvite- Diamictite and Deglaciation. The latter is formed by conglomerate, sandstone, diamictito, varvite and shale. The structure of the Deglaciation System is the same of one major cycle/Formation of Itararé Group, except for the varvite component, or rhythmite in the major cycle. Five sequences are recognized. The Campo do Tenente sequence is formed by two thick varvite-diamictite systems, from a glacicontinental system attributed to a highstand tract (the Campo do Tenente is a marginal equivalent of the marine Lagoa Azul/Roncador Bed). The Campo Mourão sequences (CM-I and CMII) begin with thick Sandstone systems from a lowstand tract; it follows Varvite- Diamictite (only for CM-I), Deglaciation and marine Shale systems, respectively from transgressive and highstand tracts (the CM-2 marine system is the thick Lontras Shale). Taciba Formation sequences TB-I and TB-II are more complex. TB-I starts with a thick, glaciomarine Diamictite system (highstand tract?), and is followed by Deglaciation system. TC-II starts with a channelized, lowstand Sandstone system, estuarine, deltaic and turbidite in origin; it follows the Deglatiation and marine Shale systems, from transgressive and highstand tracts.

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