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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.
391

Análise cronoestratigráfica baseada em conodontes da Formação Itaituba (Pedreira Calminas), Atokano da Bacia do Amazonas - Brasil

Cardoso, Cassiane Negreiros January 2011 (has links)
Conodontes são microfósseis potencialmente úteis para bioestratigrafia e em reconstruções paleoecológicas de rochas sedimentares paleozóicas e do Triássico. Desta forma, este estudo apresenta a classificação taxonômica e o estabelecimento das condições biocronoestratigráficas e paleoecológicas nas quais estes organismos viveram, bem como uma revisão do estágio atual do conhecimento a respeito dos conodontes e de seu aparelho alimentar. A seção analisada pertence à Formação Itaituba, Grupo Tapajós, Pensilvaniano da Bacia do Amazonas. A área de estudo localiza-se a Nordeste da cidade de Itaituba, às margens do Rio Tapajós, em um afloramento da Pedreira Calminas. A distribuição dos conodontes reconhecida define duas biozonas: uma Zona de Amplitude Diplognathodus orphanus e uma Zona de Concorrência Idiognathodus incurvus-Idiognathoides sinuatus. As espécies Diplognathodus coloradoensis, Diplognathodus orphanus e Idiognathodus incurvus formam uma associação tipicamente atokana. Baseando-se na associação descrita, a seção analisada foi definida como atokana. A espécie de melhor resolução bioestratigráfica é Diplognathodus orphanus, sendo sua distribuição restrita ao Atokano. O ambiente deposicional dominante na Bacia do Amazonas durante o Pensilvaniano é caracterizado por uma rampa carbonática rasa. Os depósitos estudados refletem uma sequência predominantemente regressiva, com a presença de gêneros de águas mais rasas, tais como Adetognathus, Diplognathodus e Ellisonia. A ocorrência de conodontes associados a braquiópodes, briozoários, crinóides e fragmentos de peixes sugere que estes estratos foram depositados em paleoambiente marinho raso, com energia de sedimentação baixa a moderada, em águas calmas, límpidas e quentes. No regime de flutuações de alta freqüência do nível do mar, os principais ambientes deposicionais eram laguna (submaré) e planície de maré (intermaré superior-supramaré inferior com tapetes microbiais). / Conodonts are useful microfossils for biostratigraphy and paleoecological reconstructions in Paleozoic and Triassic sedimentary rocks. This research aims to their taxonomic classification and to establish the biochronostratigraphic and paleoecological conditions in which these organisms lived. Furthermore, this study reviews the current knowledge about conodonts and their feeding apparatus. The section analyzed belongs to Itaituba Formation, Tapajos Group, Pennsylvanian of the Amazon Basin. The study area is located northeast of Itaituba city, on the banks of the Tapajós River, in an outcrop of Calminas Quarry. The distribution of conodonts recognized defined two biozones: Diplognathodus orphanus Amplitude Zone and Idiognathodus incurvus-Idiognathoides sinuatus Competition Zone. The species Diplognathodus coloradoensis, Diplognathodus orphanus and Idiognathodus incurvus are typically an Atokan association. Based on the association described, the section analyzed was defined as Atokan. The specie with better biostratigraphic resolution is Diplognathodus orphanus, because its distribution is restricted to the Atokan. The depositional environment prevailing in the Amazon Basin during the Pennsylvanian is characterized by a shallow carbonate ramp. The deposits studied reflect a predominantly regressive sequence, with the presence of shallow water genera, such as Adetognathus, Diplognathodus and Ellisonia. The occurrence of conodonts associated with brachiopods, bryozoans, crinoids and fish fragments suggests that these strata were deposited in a shallow marine environment, with low to moderate energy, in calm, clear and warm waters. In high frequency sea level fluctuations regime, the main depositional environments were lagoon (subtidal) and tidal flat (upper intertidal-lower supratidal with microbial mats).
392

The effects of minerals on reservoir properties in block 3A and 2C, within the orange basin, South Africa.

Salie, Sadiya January 2018 (has links)
>Magister Scientiae - MSc / The reservoir quality of the Orange Basin, offshore South Africa is known to be immensely impaired by the presence of authigenic minerals. The collective effects of burial, bioturbation, compaction and chemical reactions between rocks, fluid and organic matter conclusively determined the quality of reservoirs within the Orange basin. The aim of this study was to provide information on the quality of reservoirs within the Orange Basin. Data used to conduct this study include wireline logs (LAS format), well completion reports and core samples from potential reservoir zones of wells K-A2, K-A3 and K-E1. To accomplish the aim, petrophysical parameters were calculated, such as porosity, permeability and water saturation. Besides, depositional environments were identified using gamma ray log and core logging techniques. Thirdly, petrographic studies were supporting techniques in understanding how various minerals and diagenetic processes play a role in reservoir characterisation. Geophysical wireline logs (Gamma ray, Resistivity, Bulk density and Caliper) allowed for the estimation of the three main reservoir properties; namely: porosity, water saturation and permeability. The porosity calculations revealed a range of 3-18% for well K-A2, 2%-13% for well K-A3 and 3%-16% for well K-E1. The permeability’s ranged from 0.08-0.1 mD and 0.001-1.30 mD for K-A3 and K-E1, respectively. Thus, the findings of the petrophysical evaluation of the wells in Interactive Petrophysics indicated that the reservoir intervals of wells K-A2, K-A3 and K-E1 are of poor to good quality. Based on the core analyses, the depositional environment is mostly shallow marine, specifically tide dominated for well K-A2, sandstone channel for well K-A3 and intertidal environment for well K-E1. These environments were confirmed by XRD, revealing glauconite as the prominent mineral.
393

The depositional environment of Sandstone reservoirs, of wells within F-AH and F-AR field, offshore the Bredasdorp basin, South Africa

Sass, Amy Lauren January 2018 (has links)
>Magister Scientiae - MSc / This study is located within the Bredasdorp Basin which is on the southern continental margin, offshore South Africa. The basin is located between Infanta and Agulhas arches and is a rift basin that is southeastern trending. Sedimentology reports have shown that the basin is predominantly filled by Aptian to Maastrichtian deposits which overlays pre-existing late Jurassic to Early Cretaceous fluvial and shallow marine syn-rift deposits. Devonian Bokkeveld Group slates and or Ordovician-Silurian Table Mountain Group quartzites are shown to be the composition of basement rocks. The study area incorporates only three wells for this research; well F-AH1, F-AH2 and F-AR1. This paper was completed through analyzing and juxtaposing interpretations of results from gamma ray wireline log analysis with core analysis in which these correlations and figures were displayed using Petrel software and Coral Draw respectively. Core analysis resulted in the identification of, sixteen litho-facies for the entire study, which were recognized according to its grain size, texture, sedimentary structures, colour changes, base and top contacts, bioturbation, noticeable minerals, etc. Facies tend to alternate all the way through each well and between different wells with similar facies being present in different wells, but they are not evident in all the cores. Based on the classification of sand bodies, core analysis provides good indication that the general depositional environment of reservoirs within the studied wells are within a marginal marine depositional environment which are tidally influenced. Log signatures typical of sandstone reservoir bodies were discovered in the field where sand bodies are 20 m thick or less and were recognized in the study area. Depositional environments were characterized based on depositional environment similarities: a funnel-shaped facies representing a crevasse splay; a cylindrical-shaped facies representing slope channel-fills representing the transgressive-regressive shallow marine shelf.
394

Aspectos da estratigrafia das seqüências pré-carboniferas da Bacia do Paraná no Brasil / Stratigraphic aspects of the pre-carboniferous sequences in the Paraná Basin, Brazil

Assine, Mario Luis 26 August 1996 (has links)
O registro pré-Carbonífero da Bacia do Paraná é composto por duas seqüências estratigráficas limitadas por discordâncias regionais, que constituem dois ciclos de 2ª ordem: Ordoviciano/Siluriano e Devoniano. No Ordoviciano Superior/Siluriano Inferior (Gr. Rio Ivaí) foram caracterizadas duas seqüências deposicionais: 1) a inferior, considerada de idade caradociana - ashgilliana, compreende arenitos de tratos de sistemas transgressivo e de mar alto da Fm. Alto Garças, que apresentam mergulho deposicional para oeste em direção às bacias do Chaco; 2) a seqüência neo-ashgilliana - llandoveriana inicia-se com as fácies subglaciais da Fm. Iapó, correlacionadas com a glaciação gondwânica neo-ashgilliana. Folhelhos pós-glaciais da Fm. Vila Maria constitutem trato de sistemas transgressivo, com superfície de máxima inundação no Llandoveriano Inferior. A seção de topo da Fm. Vila Maria registra tendência regressiva, que culminou com a geração de discordância generalizada no Siluriano Superior. No Devoniano (Gr. Paraná) foram caracterizadas três seqüências deposicionais: 1) a seqüência basal, de presumida idade lochkoviana, resultou de rápida transgressão sobre embasamento peneplanizado, em onlap de oeste para leste, fenômeno que gerou espaço para acomodação de tratos psamíticos de sistemas transgressivo e de mar alto (partes inferior e média da Fm. Furnas). A existência de traços fósseis de trilobita corrobora a interpretação de ambientes marinhos para a Fm. Furnas; 2) fácies conglomeráticas de trato de sistemas de mar baixo (parte superior da Fm. Furnas) marcam o início da seqüência praguiana - eifeliana. O empilhamento é transgressivo na transição entre as formações Furnas e Ponta Grossa, com superfície de máxima inundação no Emsiano Superior (Mb. Jaguariaíva). O Eifeliano é caracterizado por trato de mar alto com empilhamento regressivo progradacional (Mb. Tibagi). Tectonismo sinsedimentar foi responsável pela individualização de altos internos e marginais, resultando no levantamento inicial do Arco de Assunção e na compartimentação das sub-bacias de Apucarana e Alto Garças; 3) a base da seqüência givetiana-frasniana (Mb. São Domingos) é caracterizada por rápida inundação, com presença de lags transgressivos, à qual se associa o ingresso de águas quentes e o declíneo da fauna malvinocáfrica. A superfície de máxima inundação no Givetiano corresponde à máxima transgressão no Devoniano da Bacia do Paraná. Análise regional permitiu verificar a aplicabilidade da divisão tripartite da Fm. Ponta Grossa em toda a bacia. Na faixa de afloramentos no Estado de Goiás o Mb. Jaguariaíva não ocorre e o contato com a Fm. Furnas é discordante, com presença de lags transgressivos. Na Chapada dos Guimarães a parte superior da Fm. Furnas de autores prévios foi reclassificada como Fm. Ponta Grossa. A seqüência devoniana é desigualmente preservada e recoberta em discordância levemente angular por unidades westphalianas do Gr. Itararé. As seqüências ordovício-siluriana e devoniana são aproximadamente cronocorrelatas às orogenias pré-andinas Oclóyica (Ordoviciano Superior/Siluriano Inferior) e Chanica (Devoniano Médio/Mississipiano Inferior), evidenciando correspondência entre eventos de subsidência na bacia e orogenias nas bordas da placa. / The pre-Carboniferous record of the Paraná Basin is composed of two stratigraphic sequences bounded by regional unconformities: 1) Ordovician-Silurian sequence, and 2) Devonian sequence. The Ordovician-Silurian stratigraphic sequence (Rio Ivaí Group) is characterized by two depositional sequences. The oldest one (Caradocian/Ashgillian) is made up of sandstones (Alto Garças Formation), dipping westward to the Chaco basin, herein interpreted as transgressive and highstand systems tracts. The youngest sequence (Neoashgillian/Llandoverian) begins with subglacial facies of the Iapó Formation, a correlative of several Gondwana Neoashgillian glacial records. The shales of the Vila Maria Formation (Lower Llandoverian) are the post-glacial flooding record and comprise the maximum flooding surface of the transgressive systems tracts. The upper section of the Vila Maria Formation records the regressive facies and a widespread unconformity in the Late Silurian. The Devonian stratigraphic sequence (Paraná Group) is made up of three depositional sequences: 1) the lowermost one (Lochkovian?) records, from west to east, a coastal onlap over the basement comprising the transgressive and highstand systems tracts of the Furnas Formation (lower and middle sections). The presence of trilobite trace fossils in the Furnas Formation are important diagnosis for its marine environment. 2) The middle sequence (Praguian/Eifelian) is composed of conglomerates of lowstand system tract and transgressive facies toward the contact zone with Ponta Grossa Formation. The maximum flooding surface was in the Late Emsian during the deposition of the Jaguariaíva Member. The Eifelian (Tibagi Member) is characterized by a progradational regressive stacking, typical of highstand systems tracts. Sinsedimentary tectonics were responsible for creating internal and marginal highs, such as the Asuncion Arch, and sub-basins such as the Apucarana and Alto Garças. 3) The uppermost sequence (Givetian/Frasnian) is a transgressive sequence (São Domingos Member) associated with warm currents bringing about the decline of the Malvinokaffric fauna. The Givetian maximum flooding surface overlaps the maximum transgression of the Devonian in the Paraná basin. The Devonian sequence is separated from the Itararé Group (Westphalian) by a slightly angular unconformity. The regional analysis performed in this work has also aimed the practical application of the three-fold subdivision of the Ponta Grossa Formation. It has been observed that the Jaguariaíva Member does not occur in the outcrop area of Goiás State and that the contact with the Furnas Formation, in that area, is discordant with transgressive lags. In the Chapada dos Guimarães area, Mato Grosso State, the upper part of the Furnas Formation of previous authors was reclassified as Ponta Grossa Formation. The Ordovician-Silurian and Devonian sequences in the Paraná Basin are chronocorrelated to the Oclóyica (Late Ordovician/Early Silurian) and Chanica (Middle Devonian/Early Mississippian) pre-Andean orogenic phases, showing correspondence between intraplate subsidence and orogenies in the plate edges.
395

Análise geomorfológica da bacia do ribeirão Balainho / Suzano - SP / Geomorphological analysis of Ribeirão Balainhos drainage basin / Suzano - SP

Flores, Diego Moraes 03 September 2012 (has links)
Esta pesquisa consistiu na análise geomorfológica e em um conjunto de levantamentos dos aspectos físicos da bacia hidrográfica do Ribeirão Balainho. O trabalho baseou-se no mapeamento morfométrico e morfográfico, além de observações de campo para o levantamento das características morfológicas da referida bacia. Os dados coletados visaram também estabelecer as características morfoestruturais e morfoesculturais, a fim de indicar áreas com maior potencialidade a processos denudativos. Para tal, optou-se pela utilização de cartografia geomorfológica de detalhe (1: 25.000) por meio da fotointerpretação de fotografias aéreas e de técnicas de mapeamento (morfografia) apresentadas por Tricart (1965) e Verstappen e Zuidam (1975). Quanto às técnicas na confecção das cartas morfométricas, estas se basearam nos apontamentos de Spiridonov (1981), Cunha, Mendes e Sanches (2003). As modificações morfológicas observadas, sobretudo os processos lineares de erosão foram associados a causas distintas em cada setor compartimentado da bacia (alta, média e baixa bacia), devido a características geológicas, morfológicas, pedológicas, de cobertura superficial e de usos distintos do solo. / This research is consisted of a set of data about the physical aspects of the Ribeirão Balainhos drainage basin. The study is based on morphometric and morphografic mapping and on field observations for the attainment of morphological characterization of the drainage basin. The data collected aimed to determine the morphostructural and morphosculpture characteristics, with the goal of point the areas with higher risks to suffer denudation process. For this, it was chosen the detailed geomorphological cartography (1:25.000), by the photointerpretation of aerial photographs and mapping technics (morphography), given by Tricart (1965) and Verstappen and Zuidam (1975). By the technics used in creation of the morphometrics charts, they were based on Spirodonov (1981), Cunha, Mendes and Sanches (2003) notes. The morphological changes viewed, especially the linear erosions processes, were associated to different reasons in each sector compartmented of the basin (upper, middle and lower), due the geological, morphological, pedological, surface coverage soil and land uses characteristics.
396

Revisão taxonômica e relações filogenéticas do grupo Acanthicus (Siluriformes,Loricariidae) / Taxonomic review and phylogenetic relationships of the Acanthicus group (Siluriformes, Loricariidae)

Chamon, Carine Cavalcante 10 February 2012 (has links)
O grupo Acanthicus (Siluriformes, Loricariidae) é composto por quatro gêneros: Acanthicus, Megalancistrus, Leporacanthicus e Pseudacanthicus. O monofiletismo do grupo composto por estes géneros foi previamente suportado por dados morfológicos e moleculares. Com o intuito de elucidar as relações filogenéticas entre as espécies do grupo Acanthicus foram analisados 21 representantes do grupo interno e mais 12 táxons de Ancistrini como grupos externos, com base em 121 caracteres fenotípicos de diferentes complexos anatômicos. A análise de parcimônia resultou em duas árvores igualmente parcimoniosas com 453 passos (CI= 0,32 RI= 0,66). O monofiletismo do grupo Acanthicus foi corroborado com base em 11 sinapomorfias, três destas exclusivas: crista do hiomandibular contínua a do quadrado; extremidade distal dos dentes do pré-maxilar acentuadamente curvada e quilhas na lateral do corpo bastante desenvolvidas. As relações entre os táxons do grupo Acanthicus mais Spectracanthicus resultaram na seguinte topologia: ((Spectracanthicus) (Megalancistrus, Acanthicus) (Leporacanthicus, Pseudacanthicus))). A nomenclatura genérica do grupo foi reformulada seguindo a hipótese filogenética e a revisão taxonômica resultou no reconhecimento de 18 espécies válidas no grupo Acanthicus, nove destas novas. No gênero Pseudacanthicus, P. fordii foi considerado sinônimo de P. serratus e P. histrix sinônimo de P. spinosus; ademais seis novas espécies foram descritas para as bacias dos rios Aripuanã, Tocantins, Tapajós, Curuá-Una e Xingu. Oligancistrus foi considerado sinônimo de Spectracanthicus e foram descritas três novas espécies das bacias dos rios Tapajós, Tocantins e Xingu. / The Acanthicus group (Siluriformes, Loricariidae) is currently composed of four genera: Acanthicus, Megalancistrus, Leporacanthicus e Pseudacanthicus. The monophyly of the group has been previously supported by both morphological and molecular data. To investigate the relationships among the Acanthicus group species, 21 taxa of the ingroup and 12 taxa of other Ancistrini as out-groups were studied on the basis of 121 phenotipic characters of different anatomical complexes. Parsimony analysis resulted in two most parsimonious trees with 453 steps (CI= 0,32 RI= 0,66). Monophyly of the Acanthicus group was corroborated by 11 synapomorphies, three of which exclusive: hiomandibular ridge contiguous with ridge of the quadrate, distal edge of premaxillary teeth strongly curved with well-developed keels. Relationships of the Acanthicus group plus Spectracanthicus resulted in the following topology: (Spectracanthicus ((Megalancistrus, Acanthicus) (Leporacanthicus, Pseudacanthicus))). Genus-level nomenclature of the group was reformed on the basis of the phylogenetic hypothesis and of a taxonomic revision which resulted in the recognition of 18 valid species in the Acanthicus group, nine of which new. In the genus Pseudacanthicus, P. fordii was recognized as a junior synonym of P. serratus and P. histrix of P. spinosus, with six new species from the Aripuanã, Tocantins, Tapajós, Curuá-Una and Xingu Rivers Basins. Oligancistrus was recognized as a junior synonym of Spectracanthicus and three new species were described in the latter, from the Tapajós, Tocantins and Xingu River Basins.
397

Descrição osteológica e posicionamento filogenético de um terópode (Dinosauria, Saurischia) do Cretáceo Inferior da Bacia Sanfranciscana, município de Coração de Jesus, Minas Gerais, Brasil / Osteological description and phylogenetic position of the theropod (Dinosauria, Saurischia) the Lower Cretaceous basin Sanfraciscana, city of Coração de Jesus, Minas Gerais, Brazil

Silva, Rosely Rodrigues da 27 March 2013 (has links)
A região do cráton São Francisco possui um histórico de eventos de sedimentações que datam do Paleo-Proterozóico e Mesozóico. A Bacia Sanfranciscana representa o último ciclo geodinâmico que afetou a grande Bacia Intracratônica do São Francisco. Embora o Cretáceo brasileiro seja considerado o período geológico mais bem representativo em termos de conteúdo de paleofauna de vertebrados, na Bacia Sanfranciscana este registro era restrito até recentemente apenas por celacantídeos e fragmentos de peixes do Grupo Areado. Através dos trabalhos de campos executados pela equipe do Laboratório de Paleontologia do Museu de Zoologia da USP, novos fósseis de tetrápodes continentais foram encontrados em sedimentos da Formação Quiricó, nos arredores do município de Coração de Jesus (MG). Dentre estes materiais, destacam-se elementos epipodiais, mesopodiais e metapodiais atribuíveis a um terópode. Este estudo visou descrever e comparar a osteologia do novo exemplar, tombado sob o número MZSP-PV 830, com outros registros de abelissauroideos conhecidos além de posicionar filogeneticamente com os outros táxons da irradiação de terópodes formada pelo clado Ceratosauria. Neste sentido, a análise da matriz de dados alocou-o no clado Noasauridae, com base nas seguintes características: a forma tabular do maléolo lateral da tíbia; e a forma estreita da haste do metatarsal II. A presente descrição representa uma relevância paleontológica significativa para o entendimento da diversificação dos terópodes no continente sul-americano. O material representa o primeiro registro osteológico de Noasauridae para o Brasil, o segundo representante de noassaurídeo de idade Aptiana, e é também a primeira descrição de um terópode para a região praticamente inexplorada da Bacia Sanfranciscana / The region of the São Francisco craton has a history of sedimentation events dating from the Paleo-Proterozoic and Mesozoic. Sanfranciscana Basin sedimentation represents the last geodynamic cycle that affected the large Sanfranciscana Intracratonic Basin. Despite the Cretaceous of Brazil being the best represented geological period in terms of vertebrate paleofauna, this kind of record in Sanfranciscana Basin was until recently restricted to coelacanths and fragments of fish from Areado Group. Through fieldwork performed by the Laboratory of Paleontology at the Museu de Zoologia - USP, new fossils of continental tetrapods were found in Formation Quiricó sediments, on the vicinity of the city of Coração de Jesus (MG). Among these materials, we highlight epipodials, mesopodials and metapodials elements attributable to a theropod. This study aimed to describe and compare the osteology of this new specimen, numbered as MZSP-PV 830, with other known abelisauroids and also allocate it phylogenetically among the other theropod taxa irradiation of Ceratosauria clade. In this sense, the analysis of the data matrix allocated the new taxon in the Noasauridae clade, based on the following characteristics: the tabular shape of the lateral malleolus of the tibia; and the narrow shape of the metatarsal II shaft. The present description represents a significant paleontological relevance for understanding the diversification of theropods in South America. This material represents the first osteological record of Noasauridae to Brazil, the second noasaurid representative from the Aptian age, as well is the first description of a theropod from the virtually unexplored region of the Sanfranciscana basin
398

Causes and Consequences of Plant Spatial Patterns in Natural and Experimental Great Basin (USA) Plant Communities

Rayburn, Andrew P. 01 December 2011 (has links)
The processes by which plant spatial patterns are formed, and the effects of those patterns on plant community dynamics, remain important areas of research in plant ecology. Plant spatial pattern formation has been linked to many ecological processes that act to structure plant communities at different spatiotemporal scales. Past studies of pattern formation are common, but recent methodological advances in data collection and analysis have permitted researchers to conduct more advanced observational studies of pattern formation in space and time. While studies of the effects of plant spatial patterns were formally rare, they have increased in the last decade as new types of experiments and analysis have been developed to better understand the myriad effects of plant patterns on community dynamics. My dissertation research examined both the causes and consequences of plant spatial patterns in the context of natural and experimental Great Basin semi-arid plant communities. In both cases, I implemented novel methodologies for data collection, experimental design, and data analysis in an attempt to address current gaps in knowledge related to the processes by which plant spatial patterns are formed, as well as the effect of plant spatial patterns on community dynamics. The results inform both basic and applied plant ecology, and set the stage for further research on the causes and consequences of plant spatial patterns in semi-arid plant communities.
399

An integrated study of the early cretaceous (Valanginian) reservoir from the Gamtoos Basin, offshore South Africa with special reference to seismic facies, formation evaluation and static reservoir modeling

Lasisi, Ayodele Oluwatoyin January 2019 (has links)
Philosophiae Doctor - PhD / Integrated approaches in the study of petroleum exploration are increasingly becoming significant in recent times and have yielded much better result as oil exploration is a combination of different related topics. The production capacity in hydrocarbon exploration has been the major concern for oil and gas industries. In the present work an integrated approach was made with seismic, well logs and biostratigraphy for predicting the depositional environment and to understand the heterogeneity within the reservoirs belonging to Valanginian (Early Cretaceous) age of Gamtoos Basin, Offshore South Africa. Objectively, the integrated work was mainly based on seismic stratigraphy (seismic sequence and seismic facie analysis) for interpretation of the depositional environments with combination of microfossil biostratigraphic inputs. The biostratigraphic study provides evidences of paleo depth from benthic foraminifera and information about bottom condition within the sedimentary basin, changing of depositional depth during gradual basinal fill during the Valanginian time. The petrophysical characterization of the reservoir succession was based on formation evaluation studies using well logs to investigate the hydrocarbon potential of the reservoir across Valanginian depositional sequence. Further, the static modeling from 2D-seismic data interpreted to a geological map to 3D-numerical modeling by stochastic model to quantify the evaluation of uncertainty for accurate characterisation of the reservoir sandstones and to provide better understanding of the spatial distribution of the discrete and continuous Petrophysical properties within the study area.
400

...An Already Dreamed State Already Dreaming State Already…

Alcantara, Francheska 01 January 2019 (has links)
A compendium of horizontality through the means of theory, facts, fictions, questions and other ruminations on the Caribbean and the diasporic experience.

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