Tesi: "Rocks, Sedimentary"

1

Dodd, Matthew S. "Biosignatures in Precambrian sedimentary rocks". Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10055383/.

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The overarching goal of this work was to trace the origins of organic matter as a possible biosignature for early life on Earth. This work documented the petrological, structural, isotopic, elemental and molecular properties of organic matter, in a suite of sediments ranging from the Eoarchean to the Phanerozoic. Particular attention was paid to iron formations which form a major part of the Precambrian sedimentological record. Optical and micro-Raman spectroscopy were used to document the petrological occurrences of organic matter and its associated diagenetic features. Focused ion beam and transmission electron microscopy were used to detail the nanoscale structures of the organic matter. Mass spectroscopic techniques were utilised to measure the isotopic, elemental and molecular properties of organic matter and its petrographically associated carbonate. The timing and possible mechanisms of organic matter formation were investigated and evaluated, against the observed attributes of the organic matter. This work has documented organic matter forming key mineral associations with apatite and carbonate, which point to the diagenetic recycling of biogenic carbon. The diagenetic cycling of organic matter is proposed, to fuel the formation of granules during organic matter, iron and sulphur cycling. This cycling is hypothesised to lead to heterogeneity in organic matter structure and preservation in sediments. Additionally, this work has demonstrated that fluid deposited graphite in metamorphosed sediments may represent redistributed, syngenetic organic matter, shedding light on the controversial origins of graphite biosignatures in Earths oldest rocks. Finally, a detailed study of microfossil structures and their associations with organic matter and biominerals in iron formations was conducted to provide evidence for the preservation of Proterozoic microfossils, and the earliest signs of life on Earth.

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2

Tavares, Sandra Aparecida Simionato 1969. "Fósseis do afloramento Santa Irene, cretácio superior da Bacia Bauru = inferências paleoecológicas". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287322.

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Orientadores: Frésia Soledad Ricardi Torres Branco, Ismar de Souza Carvalho
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências
Made available in DSpace on 2018-08-18T21:34:34Z (GMT). No. of bitstreams: 1 Tavares_SandraAparecidaSimionato_M.pdf: 8529535 bytes, checksum: 81caa7b6648edbc9a42d10c5ee967375 (MD5) Previous issue date: 2011
Resumo: O Afloramento Santa Irene tem sido considerado um dos mais significativos da Bacia Bauru, na Formação Adamantina, pela abundancia e boa conservação de fósseis associados ali encontrados, como dentes isolados de arcossauros carnívoros associados a fósseis de um dinossauro saurópode herbívoro. Os fósseis foram coletados nos anos de 1997 e 1998, na área rural do Município de Monte Alto - SP, e hoje compõem parte do acervo do Museu de Paleontologia de Monte Alto. Os dentes isolados de tal afloramento são o principal material de estudo deste trabalho, que, acrescidos a outros dados obtidos através da análise das feições bioestratinômicas e geológicas da região, permitiram tecer uma interpretação paleoecológica para o Afloramento Santa Irene. Foram analisados vinte e seis exemplares de dentes de arcossauros carnívoros, sendo dezoito deles enquadrados como Theropoda e oito como elementos dentários pertencentes aos Crocodyliformes. Os dentes de Theropoda se distinguem daqueles de Crocodyliformes por serem os primeiros mais achatados lateralmente, além de apresentarem serrilhas. Foi possível constatar que quatorze dos dezoito exemplares classificados dentro da Subordem Theropoda apresentam características pertencentes à Ceratosauria, família Abelisauridae, e Maniraptora, família Dromaeosauridae. A coleção de dentes de Crocodyliformes coletados no afloramento Santa Irene consiste de oito exemplares em geral cônicos, com estriamento ao longo da carena, podendo ou não apresentar bordos serrilhados e seção basal arredondada, sendo possível classificá-los dentro da família Trematochampsidae. Os fósseis articulados e com pouco desgaste do Aeolosaurus indicam um soterramento parcial logo após a morte ou ainda na fase de destruição de seus elementos não esqueléticos. A observação do afloramento e do seu entorno permitiu deduzir que a região apresentava rios, possivelmente, entrelaçados com deposição sazonal de sedimentos e períodos de estabilidade com a formação de solos incipientes. Durante os períodos interdeposicionais e de formação do solo, nota-se a ocorrência da precipitação de minerais, dando origem à formação de calcretes, resultado de períodos secos marcantes. O afloramento Santa Irene representa a deposição de rios que formavam barras arenosas, nas quais diversos grupos de animais buscavam água e alimento. Conclui-se que estes animais habitavam ou transitavam por aquele ambiente, pois não há sinais de que os fósseis tenham sido transportados até o local no qual foram coletados, mas sim que a carcaça do Aeolosaurus serviu de alimentação para outros animais no local de sua morte. Desta forma, o material analisado permitiu a reconstituição de um retrato impar de um ecossistema a muito extinto
Abstract: The Santa Irene outcrop has been considered one of the most significant of the Bauru Basin, in the Adamantina formation, because of abundance and good preservation of associated fossils found there, as isolated teeth of carnivorous archosaurs associated with fossils of a herbivorous sauropod dinosaur. The fossils were found in 1997 and 1998, in rural areas of the city of Monte Alto - SP, and today compose the collection of the Museum of Paleontology of Monte Alto. The isolated teeth from this outcrop is the main material of this paper, which, together with other data obtained by analysis of biostratonomic and geological features of the region, allowed to make a paleoecological interpretation of the outcrop Santa Irene. Twenty-six copies of teeth of carnivorous archosaurs were analyzed, eighteen of them being classified as Theropodomorpho and eight teeth as belonging to Crocodyliformes. The teeth of Theropodomorpho can be distinguished from those to be the first Crocodyliformes as they are more flattened laterally, besides having serrations. It was found that fourteen of the eighteen specimens classified within the suborder Theropoda fit the characteristics belonging to Ceratosauria, family Abelisauridae and Maniraptora, family Dromaeosauridae. The collection of Crocodyliformes teeth collected from the outcrop Santa Irene consists of eight copies generally conical, with streaking along the keel, presenting or not serrated edges and rounded basal section, being possible to classify them within the family Trematochampsidae. The articulated and with little wear fossils of Aeolosaurus indicate a burial soon after death or during the destruction of its non-skeletal elements. The observation of the outcrop and its surroundings allow deducing that the region had braided rivers with seasonal sediment deposition and periods of stability with the formation of incipient soils. During no deposicional intervals periods and soil formation, can be noted the occurrence of precipitation of minerals, giving rise to the formation of calcrete, result of striking dry periods. The outcrop of St. Irene was formed by rivers that formed sand bars, in which various groups of animals tried to find food and water. It can be deduced that these animals lived or transited through that environment, because there is no evidence that the fossils were transported to the location in which they were collected, but that the Aeolosaurus remains served as food for other animals at his death location. Thus, the analyzed material allowed the reconstitution of an unique portrait of an ecosystem to long extinct
Mestrado
Geologia e Recursos Naturais
Mestre em Geociências

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3

Malik, Qamar Mehboob. "Electrical and transport properties of sedimentary reservoir rocks". Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266398.

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4

Hattum, Marco Willem Alexander van. "Provenance of Cenozoic sedimentary rocks of northern Borneo". Thesis, Royal Holloway, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423143.

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5

Lofts, Jeremy C. "Integrated geochemical-geophysical studies of sedimentary reservoir rocks". Thesis, University of Leicester, 1993. http://hdl.handle.net/2381/35058.

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6

Chernoff, Carlotta. "Origin and redistribution of metals in sedimentary rocks". Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/289837.

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Integrated analysis of whole-rock and mineral geochemical data from black shale and metamorphosed black shale demonstrates the importance of sulfides as trace-element hosts and reveals the influence of depositional environment on whole-rock and mineral chemistries. Detailed analysis of Fe-sulfide contents provides evidence of considerable elemental redistribution during diagenesis and metamorphism, indicating that such sulfides plausibly serve as a source of metals and other elements to epigenetic fluids. Spatial and temporal analysis of the distribution of Phanerozoic black shale, phosphorite, and ironstone suggests a related geologic origin coupled to marine upwelling. Organic-rich sedimentary rocks from diverse geologic settings in China, Canada, US Great Basin, and US Mid-Continent were studied along with regionally metamorphosed black shale (Maine) and contact metamorphosed carbonaceous argillite (Nevada). Assessment of whole-rock geochemistry in these samples was supplemented with analysis of a large geochemical database compiled from published sources. Both the studied sample suite and literature database reveal systematic elemental enrichments and depletions that can be related to depositional environment. Regionally metamorphosed black shale demonstrates trace-element loss with metamorphism (Au, As, and Sb), an observation that fits well with models proposing black-shale-derived mineralizing fluids. Compositional and textural features of sedimentary and metamorphic sulfides were investigated utilizing petrographic and in situ analysis methods. Concentrations of As, Se, Ni, Co, Cu, Zn, V, Cr, and Mo in sulfides were acquired by electron microprobe. Au, Pt, and sulfur isotope contents were measured in Fe-sulfide by SIMS. Fe-sulfide data demonstrate a complex history of pyrite growth due to diagenetic, metamorphic and hydrothermal processes. Sulfur isotopes reflect bacterially mediated growth of framboidal pyrite and redistribution of this sulfur with advanced diagenesis and metamorphism. Early framboidal pyrites are enriched in many trace metals. Later diagenetic and metamorphic pyrites are typically lower in trace metal content and demonstrate recrystallization to coarser crystals. Comparison of trace elements in framboidal and coarse overgrowth pyrites shows systematic elemental changes (losses: Au, Pt, Ni, Cu, Zn, V and Cr; gains: Se; variable: As and Mo). This pattern is found in many black shales, regardless of bulk chemistry or depositional environment. Metamorphic replacement of pyrite by pyrrhotite results in similar losses from the sulfide fraction of the rock. Mass balance of the whole-rock trace inventory indicates that Fe-sulfide is an important host for As, Se, Ni, Co, and Au. These mass balance results, combined with evidence of trace element redistribution during diagenesis and metamorphism, point to a possible sourcing of metals, sulfur and other elements from black shale.

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7

Putz-Perrier, Martin W. "Distribution and scaling of extensional strain in sedimentary rocks". Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/1293.

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For this study, spatial and size distributions of normal faults and associated tensile fractures were directly measured in deformed sedimentary rocks in three extensional regions: Kimmeridge Bay and Kilve in the UK and the Maltese Islands. The collected data allow i) quantifcation of regional extension at different scales, ii) determination of the relative importance of large and small structures, iii) quan- tifcation of the spatial heterogeneity of brittle extension, iv) comparison of scaling laws for veins and faults belonging to the same extension event, and v) analysis of the evolution of brittle damage in space and time. Multiple scan-lines of different length and resolution were collected in each study area to record the entire extension-related deformation. In order to quantify the heterogeneity of fracture and strain distributions, a new method of spatial analysis has been developed. The method is based on a non-parametric comparison of the cumulative frequency and extension with that for a uniform distribution and pro- vides a measure of heterogeneity based on both the position and the displacement of individual fractures sampled along a linear traverse. Seismically observable extension is found to scale with total extension in the three study areas, obeying a power-law relationship. The proportion of the total extension that is resolved in seismic refl ection data systematically increases with increasing strain. This means that seismic data signifcantly underestimate the total extension at low strains but record most of the total extension in higher strain regions. Heterogeneity analysis carried out for the three study areas shows that i) hetero- geneities of the distributions of fractures and strain in an area can differ signifcantly, ii) heterogeneities are strongly dependent on lithology and mechanical heterogeneity, and iii) heterogeneities evolve with increasing strain. At Kimmeridge Bay, both veins and faults display power-law scaling, but do not form part of the same distribution. Veins and faults along the Kilve-Lilstock section conform to a single power-law distribution. At the Maltese Islands fault-frequencies conform to power-law scaling, but yield a higher scaling exponent in lower-strain zones than in higher-strain (damage) zones. The platform carbonates at the Maltese Islands take up early extension by randomly distributed small-scale faulting. The layered and mudstone-rich rocks around Kim- meridge Bay respond to low strain by distributed ("ductile") deformation in the shales and by randomly distributed or anti-clustered veining in the stiffer carbonate beds. In inter-bedded carbonates and shales along the Kilve-Lilstock section, early extension is highly localised in narrow zones of faults and associated damage, pre- serving large portions of virtually unfractured rock in between. A tensor method has been developed which permits three-dimensional strain analy- sis from line-data. The results of this analysis show that one-dimensional estimates of extension generally are good approximations of the maximum principal strain and that deformation in most sampled sections conforms to pure-shear, plane-strain conditions. Fold-structures associated with normal faults are explained as due to superimposed "normal drag" within the process zone and slip-related "reverse drag" within the damage zone of a (propagating) normal fault.

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8

Ruiz, Penã Franklin J. (Franklin José) 1962. "Elastic properties of sedimentary anisotropic rocks : (measurements and applications)". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/58361.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, February 1999.
Includes bibliographical references (leaves 75-78).
In multidisciplinary studies carried out in the Budare Oil Field of the Great Oficina Oil Field, there was difficulty matching well log synthetic seismograms with 2D and 3D seismic data. In addition, the seismically determined depths of reservoir horizons are greater than the well sonic log depths. To examine this discrepancy we conducted an experimental study of dynamic elastic parameters of the rocks in the oil field. We chose core representative samples of the lower Oficina Formation, the main reservoir of the field. The rocks selected were sandstones, sandy shales and dolomitized shales. For the velocity measurements, we used the ultrasonic transmission method to measure P-, Sh- and Sv-wave travel times as a function of orientation, and pore and confining pressures to 60 and 65 MPa, respectively. We found that, in room dry condition, most of the rocks studied are transversely isotropic. The stiffnesses constants, Young's moduli, Poisson's ratios, and bulk moduli of these rocks, were also calculated. The velocity anisotropies, together with the behavior of the elastic constants for dry rocks, indicate that: (1) the elastic anisotropy of the sandstones and sandy shales is due to the combined effects of pores, cracks, mineral grain orientation, lamination and foliation. The velocity anisotropies caused by the preferred oriented cracks decrease with increasing confining pressure. (2) For the dolomitized shales, the elastic anisotropy is due to mineral orientation and microlamination. In these cases the very high intrinsic anisotropy does not decrease with increasing confining pressure. (3) The velocities of compressional waves are greater in sandstones saturated with water than in the dry specimens, but the opposite behavior was found for shear waves. (4) The P-wave velocity anisotropy decreases after saturation; the magnitude of the decrease depends on the crack density and on the abundance and distribution of clay. (5) The Vsh-anisotropy does not show a pronounced change after saturation, and it is only slightly affected by confining pressure. Visual description, petrography and mineralogical analyses from thin sections and x-ray diffraction revealed the vertical and lateral heterogeneous nature of sandstones and sandy shales, whereas the dolomitized shale specimens looked homogeneous. The results of the laboratory measurements are consistent with an elastic model, using the equivalent medium theory for fine-layered isotropic and anisotropic media. However, in order to do reliable seismic migration and solve the problem of thickness calculations and time-to-depth conversion of surface seismic data, the ultrasonic data need to be extrapolated to low frequencies. Determining rock mechanical properties in situ is important in many applications in the oil industry such as reservoir production, hydraulic fracturing, estimation of recoverable reserves, and subsidence. Direct measurement of mechanical properties in situ is difficult. Nevertheless, experimental methods exist to obtain these properties, such as measurements of the stress-strain relationships (static) and elastic wave velocities (dynamic). We investigate the static and dynamic elastic behavior of sedimentary, anisotropic rock specimens over a range of confining and pore pressures up to 70 MPa, the original reservoir conditions. The static and dynamic properties are simultaneously measured for room dry shales, room dry sandstones, and brine saturated sandstones ...
by Franklin J. Ruiz Peña.
S.M.

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9

Dalrymple, Mark. "Sedimentological evolution of the Statfjord Formation fluvial hydrocarbon reservoirs of the northern North Sea". Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302647.

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The sedimentological evolution of the Statfjord Formation of the Viking Graben at the Triassic - Jurassic transition is detailed by integration of studies of mineral assemblages, isotope age data, sedimentological core analysis, palaeosol / mineralogical wireline analysis and regional correlation of subsurface wireline information, combined with theories on basin evolution in continental settings. The aim of this study is to enhance the description of, and correlation within, hydrocarbon reservoirs developed within intra-continental alluvial sediments which have been deposited in areas above the knickpoints of coastline attached incised valleys, where there is a paucity of biostratigraphical information. Sedimentological analysis of core, wireline suites and production data, allow a stratigraphic framework to be erected which can delineate reservoir flow units. In the absence of palynological datums, chronostratigraphic correlation is done by heavy mineral and geochemical analysis, distinguishing between individual flow units allowing a more genetic correlation between related sands to be made. These analytical studies also point the stratigrapher to a more accurate regional geomorphic interpretation of the core by defining units which have the same provenance, thus allowing comparison of differing sedimentological criteria within single fluvial or floodplain units. At a smaller scale, a short outcrop study of the Castisent Formation of the Spanish Pyrenees was done to illustrate the intra-alluvial sheet sand complexity present in subsurface hydrocarbon reservoirs of alluvial origin. Using data mainly from the Brent Field, Statfjord Field and Snorre Field a model for the regional evolution of the Statfjord Formation is developed. Regional correlation of the reservoir units within the Statfjord Formation, using the methods discussed above, demonstrates basic geomorphic principles which are specifically concerned with the regional development of aggradational and erosive alluvial suites in settings inland from coastal areas.

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10

Andrea, Martijn. "The anisotropic elastic properties of clay-rich rocks". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243413.

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11

Kars, Myriam. "Calibration and Application of the MagEval geothermometer in sedimentary rocks". Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3003/document.

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Pour évaluer la température d’enfouissement subie par les roches sédimentaires, une large gamme de géothermomètres est disponible, basés sur les constituants organiques ou minéralogiques de ces roches. Comme pour toutes les techniques expérimentales, elles présentent des avantages et des inconvénients. Dans cette thèse, nous utilisons une approche magnétique pour estimer la température d’enfouissement. Dans une première partie, nous avons étudié l’assemblage magnétique de puits sélectionnés à travers le monde pour mieux caractériser le géothermomètre magnétique MagEval. Deux calibrations ont pu être établies. Pour décrire la relation entre la température maximale d’enfouissement subie par les roches et leur assemblage magnétique, nous avons réalisé des expériences de chauffe en laboratoire de 50 à 130°C sur des argilites non métamorphosées. Les chauffes expérimentales ont montré que des nanominéraux magnétiques sont continuellement produits avec la température. Dans une deuxième partie, nous avons étudié les propriétés magnétiques des roches sédimentaires dans deux sites géologiques analogues pétroliers : le bassin des Grès d’Annot dans le SE de la France (température d’enfouissement 60-250°C) et les chaînes plissées de la Valley & Ridge Province dans les Appalaches, Etats-Unis (température d’enfouissement _120-200°C). Ces études suggèrent une évolution des principaux minéraux magnétiques avec la température. Magnétite, nanogoethite et pyrrhotite sont principalement formées. Les différents résultats obtenus dans cette thèse nous ont permis de proposer une évolution des minéraux magnétiques en fonction de la maturité des roches et de la température
To evaluate the burial temperature experienced by sedimentary rocks, a wide range of geothermometers is available, based on both organic and inorganic constituents of these rocks. Like all experimental techniques, they show limitations. In this thesis, we used a magnetic approach to estimate burial temperature. In a first part, we studied the magnetic assemblage of selected boreholes over the world to better characterize the magnetic geothermometer MagEval. Two calibrations were established. To assess the relationship between the peak burial temperature experienced by the rocks and their constitutive magnetic minerals, we conducted laboratory heating experiments from 50 to 130°C on unmetamorphosed claystones. The experimental heating showed that nano magnetic minerals are continuously produced with temperature. In a second part, we investigated rockmagnetic properties of sedimentary rocks from two geological plays of petroleum interest : the Grès d’Annot basin in SE France (burial temperature 60-250°C) and the fold-and-thrust belts of the Valley & Ridge Province in the Appalachians, USA (burial temperature _120-200°C). These studies suggested an evolution of the main magnetic minerals with temperature. Magnetite, nanogoethite and pyrrhotite are mainly formed. All the conducted analyses lead us to propose an evolution of the magnetic minerals as a function of the maturity of the rocks and temperature

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12

Harper, Emily. "Investigating Sedimentary Rocks to Understand Past Wet Climate of Mars". ScholarWorks@UNO, 2015. http://scholarworks.uno.edu/honors_theses/70.

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The “deltaic” geomorphology in the Eberswalde Crater is often considered a “smoking gun” for the warm-and-wet ancient climate of Mars. The Crater displays sedimentary features, which many argue, can only be found in a river-delta system (Bhattacharya et al., 2005). However, with the advent of high-resolution images, the Eberswalde Crater delta’s geomorphology has been revealed to be more complicated than could be seen previously. These high-resolution data suggest that the development of the Eberswalde delta is likely more episodic (Schieber 2007). While better resolution data has placed doubt on the wet Mars hypothesis at the Eberswalde Crater, the opposite is true of the Gale Crater. Recent images acquired by the Mars Curiosity Rover have revolutionized the hypotheses explaining the formation of Mount Sharp in the Gale Crater. The new prevailing hypothesis is that Mount Sharp was formed by a series of crater lakes (NASA, 2014). This study provides evidence supporting the crater lake hypothesis, using bedding architecture diagrams, facies diagrams, lithologic logs, paleocurrent map and rose diagram, and minimum water depth estimations of the exposed sedimentary layers. Reconstructing a detailed depositional history of the Gale Crater Lake provides a window into a more ancient Mars where life could have evolved in a wet habitable climate that is absent today.

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Key, Wendy R. O. "Fault formation in porous sedimentary rocks at high strain rates /". abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1464442.

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Thesis (M.S.)--University of Nevada, Reno, 2009.
"May 2009." Includes bibliographical references (leaves 31-37). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2009]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

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14

Noad, Jonathan James. "The sedimentary evolution of the tertiary of eastern Sabah, Northern Borneo". Thesis, Birkbeck (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369289.

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15

Robert, Rodolphe. "Analytical characterization of porous geomaterials reference assessment in some sedimentary rocks /". [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=976457164.

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16

Sisavath, Sourith. "Fundamental pore-scale modelling of single-phase flow through sedimentary rocks". Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394470.

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17

Zwing, Alexander. "Causes and Mechanisms of Remagnetisation in Palaeozoic Sedimentary Rocks - a Multidisciplinary Approach". Diss., lmu, 2003. http://nbn-resolving.de/urn:nbn:de:bvb:19-15780.

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18

Panahi, Alireza. "Geochemistry of Precambrian paleosols and Huronian sedimentary rocks, Ontario and Québec, Canada". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0021/NQ58156.pdf.

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19

Best, Angus Ian. "The prediction of the reservoir properties of sedimentary rocks from seismic measurements". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.331984.

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Recent technological advances have led to dramatic improvements in seismic resolution which now enable seismic attenuation to be measured on a routine basis. The usefulness of seismic attenuation as an interpretation parameter is restricted at present by our incomplete knowledge of the relationships between attenuation and important reservoir parameters such as porosity, permeability and the nature of the pore fluid. In order to redress this imbalance, P-wave and S-wave velocities and attenuations were measured in the laboratory at a frequency of about 0.8 MHz and at an effective pressure of 60 MPa on a set of reservoir rocks comprising twenty-seven shaly sandstones and two sandy shales. It was discovered that both P-wave and Swave attenuation increase with increasing percentage of intrapore minerals (especially clay, but also micrite) from the composition of a clean sandstone to a value of 50%, and then they decrease with increasing clay content as the rock approaches the composition of a pure shale. Porosity plays a subsidiary role to pore fill. More work is needed to predict permeability from its complex relationships with porosity and pore filling minerals. Ultrasonic P-wave and S-wave velocities (Vp and Vs) were shown to be strongly dependent on the amount of pore fill: velocity is reduced by increasing amounts of clays and micrite, but it is increased by increasing amounts of sparry calcite cement. Contrary to popular understanding, the effect on velocity of the percentage of pore filling minerals is much stronger than that of porosity on velocity, although porosity is still an important parameter. There is a strong correlation between Vp and Vs, and between P-wave quality factor (Qp) and S-wave quality factor (Qs). Interesting relationships were also discovered between Qp and Vp, and especially between Qs and Vs. However, high frequency laboratory measurements may not be representative of the low frequencies used in seismic exploration. The frequency dependence of velocity and attenuation in reservoir sandstones was investigated by exploiting the inverse relationship between frequency and pore fluid viscosity predicted by the Biot theory. P-wave and S-wave velocities and attenuations were measured at a frequency of about 0.8 MHz and at an effective pressure of 50 MPa on shaly sandstones saturated with pore fluids of viscosities 0.3 cP to 1000 cP (equivalent frequency range 2.6 MHz to 780 Hz). The Biot theory accounts for the very high Q values encountered in clean sandstones, but not the very low Q values observed in clay-rich sandstones. The observed velocity dispersion in both clean and clay-rich sandstonesim plies a local fluid flow mechanism which predicts the opposite frequency-viscosity dependence of the Biot theory. Qp and Qs in clay-rich sandstones remain constant over nearly four decades in equivalent frequency. This implies a range of relaxation times which may be attributed to the wide distribution of pore sizes of clays and other pore filling minerals. Moreover, this constant Q behaviour and the magnitude of the laboratory Qp and Qs values tie in well with those obtained from field studies. This suggests that Qp and Qs are broadly independent of frequency from seismic frequencies to ultrasonic frequencies in clay-rich sandstones.

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20

Finlay, Alexander James. "RE–OS and PGE geochemistry of organic-rich sedimentary rocks and petroleum". Thesis, Durham University, 2010. http://etheses.dur.ac.uk/399/.

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The research in this thesis is presented in paper format with each of four chapters representing one complete study. Chapter two presents Re–Os and geochemical fingerprint data for UK Atlantic margin oils. organic and δ13C geochemical data demonstrate that the oil is sourced from Upper Jurassic marine shales and the Re–Os data yields an age of 68 ± 13 Ma. Comparison of this date with published basin histories and Ar-Ar geochronology demonstrate that Re–Os ages correspond with the timing of oil generation. Furthermore the similarities between oil and source rock 187Os/188Os at the time of oil generation (Osg) indicates that Osg can be used to identify oil source units. Chapter three demonstrates, through the analysis of Kimmeridge Clay Fm. core and North Sea oil, that unradiogenic mantle like values within oils from wells in the Viking Graben and East Shetland Basin cannot be inherited from source. It is hypothesised that they are caused by contamination by a hydrothermal fluid sourced from either Cenozoic intrusive units or the mantle. Strain localisation is suggested to have caused the main basin bounding faults within the Viking Graben and East Shetland Basin to be of sufficient depth to act as conduits for hydrothermal fluid to propagate through and contaminate oils within reservoirs. Chapter four investigates how Osi values across the Ordovician/Silurian boundary GSSP at Dob’s Linn, Scotland, tracks the Hirnantian glaciation within a globally important source unit: the Ordovician/Silurian “Hot” Shales. During the Late Katian, Osi values increase from 0.28 – 1.08, providing evidence for increased silicate weathering of radiogenic continental crust. A decrease to less radiogenic Osi (~0.60) occurs at the base Hirnantian and marks the onset of the Hirnantian Glaciation. This is ascribed to Hirnantian ice cover and reduced chemical weathering rates cutting the supply of radiogenic material. In the Late Hirnantian an abrupt increase in Osi values to ~1.1 over 19 cm of stratigraphy, is attributed to the leaching of exposed radiogenic glacial deposits and increased weathering of silicate terrane during deglaciation. Chapter five applies the Platinum Group Elements, specifically Pt/Pd ratios, to identify oil source units. It is demonstrated that asphaltenes from the well constrained UK Atlantic margin petroleum system contain similar Pt/Pd and Osg values to the known source unit. A further study of the poorly constrained West Canadian Tar Sands demonstrates that Pt/Pd ratios in source rocks are not affected by hydrocarbon maturation and are distinct between differing potential source units. Comparison of the Tar Sands with potential source units demonstrates that the Tar Sands are mainly sourced from the Lower Jurassic Gordondale Fm., with minor input from the Devonian/Mississippian Exshaw Fm.

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21

Henderson, Alexandra Louise. "The geology of the Indus Basin sedimentary rocks, Ladakh Himalaya, NW India". Thesis, Lancaster University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.547983.

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22

Nunn, Jacob. "Investigations of Partial Gas Saturation on Diffusion in Low-permeability Sedimentary Rocks". Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38396.

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The effect of partially saturated conditions on aqueous diffusion was investigated on the Upper Ordovician Queenston Formation shale from the Michigan Basin of southwest Ontario, Canada. Effective diffusion coefficients (De) were determined for iodide tracer on duplicate cm-scale samples from a core segment. Partially saturated conditions were created with a new gas-ingrowth method that takes advantage of the variability of N2 solubility with pressure. The method is designed to create partially saturated pores, quantify the level of partial gas/brine saturation within the tracer-accessible pore space, and measure De under fully porewater-saturated and partially gas-saturated conditions for the same sample. X-ray radiography is used with an iodide tracer for quantifying the degree of partial saturation and measuring De. The saturated De values range from 2.8 x 10-12 to 3.1 x 10-12 m2/s. Following generation of a gas phase in the pores (average gas saturations of 4 to 6.7 %), De values decrease by 20 to 22 % relative to the porewater-saturated condition, indicating that the tortuosity factor (ratio of constrictivity to tortuosity) is sensitive to saturation. Suggesting that a small volume of the pore fraction is responsible for majority of the transport. The gas-ingrowth method was successful for generating partial gas saturation, but the distribution of the gas phase is non-uniform, with relatively high gas saturations near boundaries and lower saturations in the interior of the samples.

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23

Halsall, Carol Elaine. "The relationship between intrusive magmatism, volcanism, and massive sulphide mineralisation at Rio Tinto, Spain". Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/8894.

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24

Shakeel, Ahmed. "The effect of oriented fractures on elastic wave velocities, attenuation and fluid permeabilities of sandstones". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318186.

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25

North, C. P. "Structure and sedimentology of the Mercia Mudstone Group (Upper Triassic), Severn Estuary region, SW Britain". Thesis, University of Bristol, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233789.

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26

McCune, Julian Glenn. "Cenozoic sedimentary evolution of the Helmville Basin, west-central Montana". CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-05282008-101831/.

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27

Vieira, Lucas Valadares. "Arquitetura de fáceis e estratigrafia de sequências em alta resolução do sistema eólico fluvial e marinho raso da Formação Piauí, carbonífero da Bacia do Parnaíba, Brasil". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/182022.

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A Formação Piauí registra a deposição de um sistema eólico, fluvial e marinho raso acumulado em uma bacia de sinéclise intracratônica. A caracterização das associações de fácies e do arcabouço estratigráfico foi feito através de uma descrição detalhada das fácies sedimentares e levantamento de perfis de afloramentos. As fácies foram classificadas de acordo com a textura dos grãos (tamanho e seleção) e estruturas sedimentares observadas. Medidas de paleocorrentes foram feitas nas estratificações e laminações cruzadas. Os perfis foram medidos na escala 1:50 em locais com boa exposição vertical. Seis associações de fácies foram reconhecidas, dunas e interdunas eólicas, lençóis de areia eólicos, canais fluviais, canais fluviais influenciados por maré, shoreface superior e shoreface inferior. Através da correlação das superfícies estratigráficas as associações de fácies foram organizadas em tratos de sistema, que formaram oito sequências deposicionais de alta frequência, delimitados por discordâncias subaéreas. Estas sequências são compostas por um trato de sistemas de nível baixo (TSNB), que é dominado por sistemas eólicos ou fluviais, um trato de sistemas transgressivo (TST), que é formado por canais fluviais influenciados por maré e/ou depósitos de shoreface superior e inferior com empilhamento retrogradacional, e um trato de sistemas de nível alto (TSNA), que é formado por depósitos de shoreface superior e inferior com empilhamento progradacional. Duas sequências deposicionais de mais baixa frequência foram determinadas ao observar o empilhamento das sequências de alta frequência. Ambas as sequências são formadas por uma regressão inicial seguida por uma transgressão progressiva. O principal controle das variações no nível relativo do mar durante a acumulação da Formação Piauí foi glacio-eustático. Contudo, mudanças climáticas estavam associadas com as fases glacio-eustáticas e influenciaram a deposição eólica e fluvial.
The Piauí Formation records the deposition of aeolian, fluvial and shallow marine systems accumulated in a cratonic sag basin. Characterization of the facies associations and sequence stratigraphic framework was done by detailed description of sedimentary facies and logging of outcrops. The facies were classified based on grain texture (size and selection) and sedimentary structures observed. Paleocurrent orientations were measured from cross-strata. Stratigraphic sections were measured at a 1:50 scale at outcrops with good vertical exposure. Six facies associations were recognized: aeolian dunes and interdunes, aeolian sandsheets, fluvial channels, tidally-influenced fluvial channels, upper shoreface and lower shoreface. Through correlation of stratigraphic surfaces the facies associations were organized in system tracts, which formed eight high frequency depositional sequences, bounded by subaerial unconformities. These sequences are composed of a lowstand system tract (LST), that is aeolian-dominated or fluvial-dominated, a transgressive system tract (TST) that is formed by tidally-influenced fluvial channels and/or upper and lower shoreface deposits with retrogradational stacking, and a highstand system tract (HST), which is formed by lower and upper shoreface deposits with progradational stacking. Two low frequency cycles were determined by observing the stacking of the high frequency cycles. Both sequences are formed by an initial regression followed by a progressive transgression. The main control on sedimentation in Piauí Formation was glacioeustasy, which was responsible for the changes in relative sea level. Even though, climate changes were associated with glacioeustatic phases and influenced the aeolian and fluvial deposition.

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28

Minehan, Kathleen. "Paleotectonic setting of Takla Group volcano-sedimentary rocks Quesnellia, North Central British Columbia". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59412.

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Upper Triassic Takla Group rocks occur in Quesnellia and Stikinia, two allochthonous terranes of the Canadian Cordillera. The terranes are separated by the major, north-northwest trending, dextral transcurrent Findlay fault. The stratigraphy of the study area, east of the fault in Quesnellia, is comprised of interlayered volcaniclastic, volcanic, and sedimentary rocks. The strata have been intruded by abundant dykes, a felsic pluton, and satellite intrusions of an Alaskan-type ultramafite. Volcaniclastic rocks range from basic to felsic compositions and were deposited by several pyroclastic flows which originated subaerially and flowed into water. Igneous rocks are believed to have been comagmatic and differentiated by fractional crystallization. Major and trace element discrimination diagrams indicate an island arc tectonic setting. On the same basis, Takla Group rocks on the Stikinia side of the Findlay fault are distinguishable and more characteristic of oceanic island tectonic setting. It is recommended that the rocks of the study area be renamed Johanson Group.

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29

Hill, Kristina M. "Diagenetic and compositional controls of wettability in siliceous sedimentary rocks, Monterey Formation, California". Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1587286.

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Modified imbibition tests were performed on 69 subsurface samples from Monterey Formation reservoirs in the San Joaquin Valley to measure wettability variation as a result of composition and silica phase change. Contact angle tests were also performed on 6 chert samples from outcrop and 3 nearly pure mineral samples. Understanding wettability is important because it is a key factor in reservoir fluid distribution and movement, and its significance rises as porosity and permeability decrease and fluid interactions with reservoir grain surface area increase. Although the low permeability siliceous reservoirs of the Monterey Formation are economically important and prolific, a greater understanding of factors that alter their wettability will help better develop them. Imbibition results revealed a strong trend of decreased wettability to oil with increased detrital content in opal-CT phase samples. Opal-A phase samples exhibited less wettability to oil than both opal-CT and quartz phase samples of similar detrital content.

Subsurface reservoir samples from 3 oil fields were crushed to eliminate the effect of capillary pressure and cleansed of hydrocarbons to eliminate wettability alterations by asphaltene, then pressed into discs of controlled density. Powder discs were tested for wettability by dispensing a controlled volume of water and motor oil onto the surface and measuring the time required for each fluid to imbibe into the sample. The syringe and software of a CAM101 tensiometer were used to control the amount of fluid dispensed onto each sample, and imbibition completion times were determined by high-speed photography for water drops; oil drop imbibition was significantly slower and imbibition was timed and determined visually. Contact angle of water and oil drops on polished chert and mineral sample surfaces was determined by image analysis and the Young-Laplace equation. Oil imbibition was significantly slower with increased detrital composition and faster with increased silica content in opal-CT and quartz phase samples, implying decreased wettability to oil with increased detrital (clay) content. However, contact angle tests showed that opal-CT is more wetting to oil with increased detritus and results for oil on quartz-phase samples were inconsistent between different proxies for detritus over their very small compositional range. Water contact angle trends also showed inconsistent wetting trends compared to imbibition tests. We believe this is because the small range in bulk detrital composition between the "pure" samples used in contact angle tests was close to analytical error and because small-scale spatial compositional variability may be significant enough to effect wettability. These experiments show that compositional variables significantly affect wettability, outweighing the effect of silica phase.

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30

Chen, Guohui. "Provenance-related studies of Triassic-Miocene Tethyan sedimentary and igneous rocks from Cyprus". Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33185.

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Cyprus comprises three tectono-stratigraphic terranes: first, the Troodos Massif made up of Late Cretaceous oceanic lithosphere and its sedimentary cover in the centre of the island; secondly, the Mamonia Complex (and Moni Melange) a passive margin lithological assemblage in the west (and south) and thirdly, the Kyrenia Range, an active margin lithological assemblage in the north. This study focuses on the sedimentary cover of the Troodos Ophiolite in W Cyprus, the Triassic-Cretaceous sedimentary rocks of the Mamonia Complex and Late Cretaceous-Miocene igneous and sedimentary rocks in the Kyrenia Range, mainly based on combined sedimentology, geochemistry and geochronological dating. The Late Triassic-Early Cretaceous Mamonia Complex, SW Cyprus (and the Moni Melange, S Cyprus) represent parts of the emplaced passive continental margin of the S Neotethys. Late Triassic sandstones are characterised by a predominantly felsic source, with a subordinate mafic contribution. Jurassic-Early Cretaceous sandstones have a polycyclic felsic origin. Geochemical analyses are suggestive of progressive weathering and sediment recycling/sorting. The dominance of Ediacaran-Cryogenian and Tonian-Stenian-aged detrital zircon populations is suggestive of an ultimate north Gondwana source, probably recycled from Palaeozoic siliciclastic sedimentary rocks within Anatolia to the north. Similar detrital zircon populations characterise Early Cretaceous deltaic sandstone of the Moni Melange, S Cyprus. Sporadic Late Cretaceous subduction-related magmatism, represented by a Campanian volcaniclastic sequence (80.44±1.0 Ma) inWCyprus and a Late Campanian felsic volcanogenic sequence (72.9±1.0 Ma) in N Cyprus, represents early and more advanced stages of northward subduction during closure of the S Neotethys. Specifically, the Kannaviou Formation in W Cyprus (up to 750 m thick) is made up of deep-marine volcaniclastic sandstones that were mostly deposited by gravity flows and as air-fall tuff, interbedded with clay and radiolarian mudstones. Petrographic and geochemical analyses are indicative of a volcanic arc source, with deposition in a fore-arc basin. Petrographic evidence of terrigenous input (e.g. muscovite, muscovite schist, polycrystalline quartz) points to a subordinate continental source. Mineral chemistry is consistent with a volcanic arc origin. Elevated trace-element ratios in undevitrified volcanic glass (e.g. Th/Nb, Th/La) are indicative of involvement of continental crust or subducted terrigenous sediments in source-arc melting. Felsic volcanogenic rocks (Fourkovouno (Selvilitepe) Formation) in the Kyrenia Range, N Cyprus, occur as an up to 400 m-thick sequence of felsic tuffs, felsic debris-flowdeposits and rhyolitic lava flows. Geochemical analyses are indicative of evolved high-K and shoshonitic compositions, similar to those of the Andean active continental margin. Subduction continued to affect the northern continental margin of the S Neotethys in the Kyrenia Range during the Maastrichtian. This lead to the accumulation of Late Cretaceous sandstone turbidites and related basaltic volcanics, possibly in a back-arc setting. The volcanism took place in two phases (Late Cretaceous and Palaeogene-Early Eocene) during pelagic carbonate accumulation. These lavas have within-plate affinities, but with a variable subduction influence in some areas (e.g. western Kyrenia Range), which may be contemporaneous or inherited from previous subduction. The sedimentary sequences in the Kyrenia Range, N Cyprus, document diachronous closure of the S Neotethys. Late Cretaceous and Eocene sandstone turbidites, and the lower part of the overlying Oligocene-Miocene succession exhibit enrichment in ultramafic components that was probably sourced from ophiolite-related rocks in the Taurides to the north. In contrast, Miocene sandstone turbidites higher in the sequence show an increasing input of continent-derived siliciclastic material (and sorting effects). The terrigenous-influenced sediments are likely to represent erosion of thrust sheets that were emplaced from the S Neotethys onto the Arabian foreland in SE Turkey related to continental collision. Ediacaran-Cryogenian and Tonian-Stenian-aged zircons dominate the Late Cretaceous and Eocene sandstone turbidites, consistent with derivation from the Tauride micro-continent to the north and/or NE. Overlying Miocene sandstones include minor populations of Neoproterozoic-aged zircons, suggestive of reworking from source rocks of ultimately Gondwanan origin (e.g. NE Africa/Arabian-Nubian Shield). In summary, the thesis results exemplify the interaction of tectonic processes associated with the evolution of the S Neotethys Ocean. This began in the area studied with passive margin development (Triassic-Cretaceous), and was followed by multi-stage subduction-related volcanism and sedimentation (Late Cretaceous-Miocene). Final closure of the S Neotethys in this area took place during the Late Miocene-Recent.

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31

Bouchard, Laurianne. "Rb-Sr Age Estimates of Pore Fluids in Sedimentary Rocks, DGR Site, Kincardine, Ontario". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32271.

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This study is part of a project aiming for the long-term burying of nuclear wastes in Kincardine, Ontario. Bedrock formations as well as their associated waters were analyzed in drill cores from the Michigan sedimentary basin, southwest Ontario. This research utilizes geochemistry combined to strontium and rubidium isotope ratios in order to determine the origin of porewaters from Ordovician shales and limestones. It is demonstrated that these waters are the result of a mixing line between the Silurian (Guelph) and Cambrian groundwaters. This last end-member was also mixed with Precambrian brines to some extent. Strontium and rubidium isotopes also demonstrated rubidium in clays were leached by porewaters over time. Once in solution, radioactive rubidium decayed into strontium over time. This process explains the accumulation of radiogenic strontium observed in porewaters. An age estimate for the deposition of carbonates and other evaporates was calculated with the Rb-Sr isotope system. The calculated age is 453.7 million years before present for dolomites, which is consistent with the history of the site. It was possible to gen an approximate age of 339.7 million years for the formation of illites. This corresponds to the illitization process that occurred after the deposition of rocks, when the Silurian brines infiltrated the deeper Ordovician shale. It was also possible to estimate of porewaters ages.

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32

Wang, Wei, e 王伟. "Sedimentology, geochronology and geochemistry of the proterozoic sedimentary rocks in the Yangtze Block, South China". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/196033.

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The South China Craton comprises the Yangtze Block in the northwest and Cathaysia Block in the southeast. Located in the southeastern Yangtze Block, the Jiangnan Orogen formed through the amalgamation between the Yangtze and Cathaysia Blocks. The Yangtze Block has sporadically exposed Archean rocks in the north, Paleoproterozoic to Mesoproterozoic volcano-sedimentary sequences in the southwest and widespread Neoproterozoic sedimentary sequences accompanied by syn-sedimentary igneous rocks on the western and southeastern margins. The late Paleoproterozoic to early Mesoproterozoic Dongchuan, Dahongshan and Hekou groups in the southwestern Yangtze Block formed in a series of fault-controlled, rift-related basins associated with the fragmentation of the supercontinent Columbia. These sedimentary sequences were deposited between 1742 and 1503 Ma, and recorded continuous deposition from alluvial fan and fluvial sedimentation during the initial rifting to deep marine sedimentation in a passive margin setting. Sedimentation during initial rifting received felsic detritus mainly from adjacent continents, whereas sedimentation in a passive margin basin received detritus from felsic to intermediate rocks of the Yangtze Block. Paleoproterozoic to Mesoproterozoic rift basins in the southwestern Yangtze Block are remarkably similar to those of north Australia and northwestern Laurentia in their lower part (1742-1600 Ma), but significantly different after ca. 1600 Ma. The southwestern Yangtze Block was likely connected with the north Australia and northwestern Laurentia in Columbia but drifted away from these continents after ca. 1600 Ma. Traditionally thought Mesoproterozoic sedimentary sequences in the southeastern Yangtze Block are now confirmed to be Neoproterozoic in age and include the 835-830 Ma Sibao, Fanjingshan and Lengjiaxi groups, and 831-815 Ma Shuangqiaoshan and Xikou groups. These sequences are unconformably overlain by the ~810-730 Ma Danzhou, Xiajiang, Banxi, Heshangzheng, Luokedong and Likou groups. The regional unconformity likely marked the amalgamation between the Yangtze and Cathaysia Blocks and thus occurred at ~815-810 Ma. The lower sequences (835-815 Ma) received dominant Neoproterozoic (~980-820) felsic to intermediate materials in an active tectonic setting related to continental arc and orogenic collision, whereas the upper sequences represent sedimentation in an extensional setting with input of dominant Neoproterozoic granitic to dioritic materials (~740-900 Ma). The upper parts of the Shuangqiaoshan and Xikou groups, uncomfortably underlain by lower units, are molasse-type assemblages with additional input of pre-Neoproterozoic detritus, representing accumulation of sediments in a retro-arc foreland basin associated with the formation of the Jiangnan Orogen. Stratigraphic correlation, similarly low-δ18O and tectonic affinity of igneous rocks from different continents suggest that the Yangtze Block should be placed in the periphery of Rodinia probably adjacent to northern India. Paleoproterozoic (~2480 Ma and ~2000 Ma) and Early Neoproterozoic (711-997 Ma) were the most important periods of crustal and magmatic events of the southeastern Yangtze Block, but there is a lack of significant Grenvillian magmatism. Early Neoproterozoic magmatism highlights the contribution from both juvenile materials and pre-existing old crust, whereas ~2480 Ma and ~2000 Ma events are marked by reworking of pre-existing continental crust. Magmatism at 1600-1900 Ma was dominated by reworking of pre-existing crust, whereas the 1400-1600 Ma magmatic event recorded some addition of juvenile materials.
published_or_final_version
Earth Sciences
Doctoral
Doctor of Philosophy

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33

Zhang, Xiping. "Geochemical exploration for polymetallic ores in volcano-sedimentary Rocks : studies in China and Finland /". Oulu : Oulun Yliopisto, 2000. http://herkules.oulu.fi/isbn9514257871.

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34

Legault, Marc Ian. "Petrology and geochemistry of Timiskaming Group sedimentary rocks, Kirkland Lake area, Abitibi greenstone belt". Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6510.

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The Timiskaming Group is a late Archaean syn-tectonic lithological unit which lies unconformably on greenstone-belt volcanic rocks and consists of an alluvial-fluvial assemblage intercalated with alkalic volcanic rocks and a turbidite assemblage. The fine-grained sedimentary rocks of the alluvial-fluvial assemblage and turbidite north unit have similar mineralogical and chemical compositions such as high SiO$\sb2$, U, Th and total rare-earth elements (REE). The turbidite south unit has high Fe$\sb2$O$\sb{3(\rm tot)}$, MgO, TiO$\sb2$, Cr and Ni. Petrographic and geochemical examinations of clasts from the alluvial-fluvial assemblage indicate that the clasts are mostly igneous rocks with minor sedimentary rocks. Four major types of igneous clasts are recognized: calc-alkaline porphyries, trachytes, trondhjemites and tholeiitic basalts. Results indicate that the turbidite south unit is the oldest unit of the Timiskaming Group and the age of sedimentation is bracketed between 2685 Ma and 2700 Ma. It was derived from an undissected arc terrane uplifted during accretion. Sources for the turbidite south unit estimated from chemical compositions of shales are 12% rhyolite, 18% komatiite and 70% andesite. The alluvial-fluvial assemblage and turbidite north unit are inferred to have been derived from a dissected island arc after accretion, but before the unroofing of K-rich intrusions, which are presently extensively exposed. A source comprising 60% calc-alkaline porphyries, 20% trachytes and 20% tholeiitic basalts is estimated for the turbidite north unit from the chemical composition of shales. The distribution of trachyte clasts in the alluvial-fluvial assemblage only close to the Lander Lake-Cadillac Fault (LLCF) suggests that displacement along the fault may have created conduits for alkaline magmas. Similar lithology of conglomerates north and south of the fault suggests that the alluvial-fluvial assemblage was deposited in a pull-apart basin after juxtaposition of two tectonic blocks along the fault between 2685 and 2677 Ma. (Abstract shortened by UMI.)

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35

Gunawan, Indra. "Mesozoic and Cenozoic siliciclastic sedimentary rocks of the Bird's head of new Guinea, Indonesia". Thesis, University of London, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603458.

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The Bird's Head area of New Guinea is underlain by Australian continental crust and has a relatively complete Palaeozoic to Recent stratigraphic record . There are a number of siliciclastic dominated formations which include the Mesozoic Tipuma Formation and the Cenozoic Sirga, Klasafet, Klasaman. and Steenkool Formations. The aim of this study was to investigate their provenance, date them better, and interpret their significance for the history of New Guinea. New fieldwork was carried out, complemented by analysis of light and heavy minerals, X-ray diffraction of clay minerals, U-Pb zircon geochronology, and quartz CL luminescence study. The Tipuma Formation was previously dated only by its stratigraphic position and was suggested to have been deposited in a continental passive margin. This study shows sands tones and conglomerates were sourced from acid volcanic, metamorphic, and recycled sedimentary rocks to the north of the formation, and from the North Australian Craton. The youngest zircon ages indicate it was deposited in the Triassic. It records long-lived Palaeozoic volcanic activity interpreted to indicate subduction of the palaeo-Pacific oceanic plate under the Australian continent associated with an Andean-type active margin that followed the Tasman Line. It is suggested that the Tasman Line continued from eastern Australia, through New Guinea, into the Bird's Head region which was part of Australia since at least the Triassic. The Oligocene-Miocene Sirga Formation was previously interpreted as related to collision of New Guinea with Pacific are terranes but there is no evidence of arc-derived material in Sirga Formation sandstones. Some quartz-rich sandstones mapped as Sirga Formation contain Pliocene zircons. The Upper Neogene siliciclastic rocks of the Bird's Head were deposited in an extensive flood plain to a shallow-marine environment. All contain evidence of acid magmatism. They were also sourced from volcanic or hypabyssal equivalents of Upper Carboniferous to Triassic intrusive bodies , older sedimentary rocks, and the Kemum Formation. 3

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36

Abdullah, Wan Hasiah. "A regional organic geochemical evaluation of sedimentary rocks of Spitsbergen and their hydrocarbon potential". Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386050.

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37

Mustard, Peter Steele Carleton University Dissertation Geology. "Upper proterozoic-lower cambrian sedimentary rocks of the Mount Harper group, Ogilvie mountains, Yukon". Ottawa, 1990.

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38

Souza, André Alves de. "Estudo de propriedades petrofísicas de rochas sedimentares por Ressonância Magnética Nuclear". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-26072012-161426/.

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A Ressonância Magnética Nuclear (RMN) é uma das técnicas mais versáteis de investigação científica experimental, com destaque para o estudo da dinâmica, estrutura e conformação de materiais. Em particular, sua utilização na ciência do petróleo é uma de suas primeiras aplicações rotineiras. Metodologias desenvolvidas especificamente para atender esta comunidade científica mostraram-se desde cedo muito úteis, sendo o estudo da interação rocha/fluido uma de suas vertentes mais bem sucedidas. Desde então, importantes propriedades petrofísicas de reservatórios de óleo e gás têm sido determinadas e entendidas, tanto em laboratório quanto in-situ, nas próprias formações geológicas que armazenam esses fluidos. Entre estas propriedades, a permeabilidade, porosidade e molhabilidade de um reservatório figuram dentre as mais importantes informações estimadas. Com essa finalidade, a determinação e correlação dos possíveis efeitos que a interação rocha/fluido pode causar nos fenômenos de relaxação magnética e difusão molecular, tais como influência da susceptibilidade magnética e geometria do espaço poroso, foram estudados em onze rochas sedimentares retiradas de afloramentos, que possuem propriedades petrofísicas similares àquelas apresentadas por rochas reservatório de petróleo. Os resultados mostraram que os tipos de interação rocha/fluido, detectáveis pelos experimentos de RMN, são por sua vez influenciados pelas características geométricas e estruturais do meio poroso, sendo possível obter essas informações pelos resultados de RMN. Assim, este trabalho teve como objetivo principal estudar e estabelecer essas correlações, afim de se obter informações petrofísicas com maior acurácia e abrangência. Em particular, o estudo da razão T1/T2, que é a razão entre os tempos de relaxação longitudinal e transversal, típicos parâmetros envolvidos numa medida de RMN, mostrou ser um parâmetro útil no estabelecimento destas correlações. Ainda, diferentes metodologias para se medir estes e outros parâmetros de RMN foram estudadas e propostas, cuja interpretação conjunta mostrou ser fundamental para o entendimento dessas correlações. A permeabilidade das rochas, importante parâmetro que define as propriedades de transporte de fluidos dentro da matriz porosa, foi estimada aplicando-se essas metodologias propostas, mostrando excelentes resultados. Através do uso da técnica de RMN em estado-estacionário, esses resultados podem ser estendidos para a escala de well-logging, fato que aumenta consideravelmente a importância desses resultados. Uma vez consolidadas as medidas in-situ, as metodologias propostas deverão auxiliar a indústria de exploração e produção de petróleo a otimizar seus métodos e estratégias de produção, reduzindo seus custos e aumentando a vida útil de seus reservatórios.
The Nuclear Magnetic Resonance (NMR) technique is one of the most versatile techniques for scientific research, specially for the study of dynamics, structure and conformational of materials. In particular, its application in oil science is one of its first routine applications. Methodologies developed specifically to match this scientific community proved to be very useful, and the study of rock/fluid interactions is one of its most successful cases. Since then, important petrophysical properties of oil and gas reservoirs have been determined and understood both in the laboratory and inside the geological formations that store those fluids. Among these properties, the permeability, porosity and wettability of a reservoir formation are the most important information to be estimated. For this purpose, the determination and correlation of possible rock/fluid interaction effects that cause alterations on magnetic relaxation phenomena and molecular diffusion, such as the influence of the magnetic susceptibility and geometry of the porous space, were studied in eleven sedimentary rock cores taken from outcrops, since they have the same petrophysical properties presented by oil reservoir rocks. The results obtained confirmed that the types of rock/fluid interactions, detectable by the NMR experiments, are for instance influenced by the porous media geometry and structure, being possible so to obtain such information using those NMR results. Thus, the main goal of this work was the study and establishment of these correlations, in order to obtain petrophysical information with greater accuracy and comprehensiveness. In particular, the study of the T1/T2 ratio, which is the ratio of longitudinal and transverse relaxation times, common parameters strongly involved in a typical NMR measurement, was found to be useful in establishing those correlations. Moreover, different methodologies to measure this and other NMR parameters were studied and proposed, whose joint interpretation proved to be fundamental for the success of these correlations. The permeability of the rocks, an important parameter that controls the fluid transport properties inside the porous matrix, was estimated using the proposed methodologies, showing excellent results. Appling the steady-state NMR technique, those results could be extended to the well-logging scale, which could improve considerably the importance of that results. Once confirmed in measurements in-situ, the proposed methodologies will be able to help the production and exploration industry to optimize their production methods and strategies, thereby reducing production costs and increasing the reservoir lifetimes.

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39

Baskerville, Stuart Linsey. "The Carboniferous (Courceyan-Chadian) sedimentary facies mosaic of the Keel-Ardagh area of County Longford, Eire". Thesis, University of South Wales, 1998. https://pure.southwales.ac.uk/en/studentthesis/the-carboniferous-courceyanchadian-sedimentary-facies-mosaic-of-the-keel-ardagh-area-of-county-longford-eire(494fa07a-0492-496c-b3f3-913a96732ef9).html.

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The stratigraphic relationships and sedimentary environments of the Silurian, Devonian and Lower Carboniferous lithologies in the Keel area are deduced and described. This was accomplished by the analysis of over 10.000M. of diamond drilled core from the area. The oldest rocks are Silurian shales with turbidites. Deposition was in forearc basins in an active subduction zone on the north margin of lapetus. The area was one of net erosion in the Lower Devonian following the continental collision which closed lapetus. The Upper Devonian of the area is represented by the Microconglomerate lying unconformably on the Silurian. This lithology was produced by braided streams draining the immediate Keel area. The earliest Carboniferous sediments are an assemblage of sandstones and conglomerates. The Lower Quartz Sandstone was laid down in sandy braided streams. The drainage basin of the Keel rivers was considerably larger by this time and sediment was derived from western Ireland. Uplift in western Ireland made quartz pebbles and higher stream velocities to transport them available. These pebbles formed the Quartz Pebble Conglomerate deposited in pebbly braided streams. Lowering of the source area by erosion resulted in reduced sediment grain size. Sandy braided streams again dominated the Keel area and deposited the Upper Quartz Sandstone. Owing to the sea transgressing from the south marginal marine sediments were then deposited in the area, these being represented by the Lower Mixed Beds. During the advancing transgression facies belts were moving northwards. Lagoonal (Navan Micrite) deposits were laid down behind a barrier complex now represented by the Upper Mixed Beds. To seaward of the barrier shallow marine calcareous sediments were deposited on a homoclinal ramp. These are represented in the Keel area by the Shaley Pales and the Bioclastic Limestone Unit. Further to seaward Waulsortian type mudmounds were deposited on the deeper ramp. Owing to the transgressive regime existing in the Lower Carboniferous each facies belt moved northwards over the Keel area. At the close of the Courceyan partial subsidence of the ramp took place and basinal/slope shales with turbidites (Calp) were deposited as lateral equivilants of the shallower Oakport Limestone on the surrounding shelf remnent.

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40

Keene, David G. "An analysis of fracture systems, lithologic character and kinematic history of Paleozoic rock formations in a portion of southeastern Indiana". Virtual Press, 1989. http://liblink.bsu.edu/uhtbin/catkey/722793.

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This is an analysis of fractures occurring within the Paloezoic sedimentary rocks in a portion of southeastern Indiana. Fifteen hundred seventy-two fractures were used in analysis of distribution, orientation, pervasiveness, persistence, and intensity. The data collected is representative of eight counties and seventeen different collection sites.All fracture data were given an associated numerical value identifying each variable used for analysis and recorded into computer data files. A computer program was used for statistical analysis and construction of equal area nets which graphically displayed the distribution of variables. The compilation of the fracture data allowed for close interpretative analyses of variables and correlation of the orientation and distribution of the fractures within the study area.This study revealed that two orthogonal fracture systems exist in southeastern Indiana. The fracture set containing the largest percentage of those measured is oriented N11W with its compliment oriented N73W. The orientation of the second largest fracture set is N8E with its compliment oriented N82°W.The effects of the tectonic history as well as contemporary stress on the area are discussed relative to their effects on the overall distribution of fracture sets.Evidence is presented to substantiate a reactivation of the Cincinnati Arch as indicated in the Devonian-Mississippian lithologic units from data collected in the southeastern portion of the study area. Fracture data correlating to these units displays a rotation of the major fracture set maxima 90w. This data is supported by radiometric dates from the Belfast member of the Brassfield Limestone in which Laskouski, et.al., correlated a reactivation of the arch.Also within this study are lithologic descriptions of all the Paleozoic formations used for data collection. These descriptions were developed over a three year period from extensive field observation.A map of the study area is presented displaying the distribution and orientation of the fractures recorded at each data collection site.
Department of Geology

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41

Peterson, John Aaron. "Geochemical Provenance of Clastic Sedimentary Rocks in the Western Cordillera: Utah, Colorado, Wyoming, and Oregon". DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/439.

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Sedimentary rocks are an important source of information about previous orogenic conditions and the composition of which may describe the evolution of provenance and tectonic setting. Many factors influence sediment composition, namely, source rock composition, chemical weathering, climate, transport burial, and diagenesis. As the sediment composition changes through time, the geochemical characteristics of the sediment can be used to understand its geologic history. The geochemical characteristics of clastic sedimentary rocks are useful in determining the depositional setting and its associated provenance. Although many different studies have used geochemical discriminants to evaluate provenance and tectonic settings, none have used a defined geochemical method. This study evaluates the present-day geochemical approaches to see which, if any, are the most useful.

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42

Beasley, Justin M. "Geochemistry and fluid evolution of a carboniferous-hosted sphalerite breccia deposit, Isle of Man". Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6524.

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Thesis (M.S.)--University of Missouri-Columbia, 2008.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed July 14, 2009). Includes bibliographical references.

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43

Grobbelaar, Mareli. "A comparison between diamictites at the Witteberg-Dwyka contact in southern South Africa". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97091.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Diamictites are sedimentary deposits that originate from a number of different environments, the most common being associated with a glacial environment. Although this association is not, in all cases correct, it is still being used due to the lack of knowledge to confidently identify, classify and interpret a depositional environment for diamictite deposits. During the late Carboniferous to early Permian, two diamictite deposits formed during the development of the Cape Basin and Main Karoo Basin in the southern margins of South Africa. These deposits are known as the Miller diamictite and Dwyka diamictite. The latter is well known and was deposited during the Karoo-deglaciation. The Dwyka diamictite is often referred to as Dwyka Tillite. This is an inappropriate reference owing to that not all of the Dwyka deposits are directly formed as a result of glacial contact. The origin of the Miller diamictite is uncertain, but there are suggestions that its origin can be traced to either a glacial or debris flow deposit formed in a deltaic environment, thus referred to by some as a tillite and others as a diamictite. To establish the sedimentary environments of the above mentioned diamictite deposits in the study area, two facies models were presented with a notable bias for the second model. The first model represents a continuous sedimentation cycle between the closing of the Cape Basin and opening of the Main Karoo Basin, whereas the second model demonstrates an erosional break (hiatus) between the depositions of the above mentioned basins. Derived from the use of the second model, it can be concluded that the Miller diamictite can indeed be classified as a diamictite from a textural interpretation. Both diamictites (Miller and Dwyka) cannot be referred to as tillite deposits since none show evidence of direct glacial contact. The Miller and the Dwyka are both diamictites, but were formed in different sedimentary environments. The Miller diamictite is a product of debris flow deposits from the slope of a braided delta, whereas the Dwyka diamictite represents distal glacio-marine “rain-out” deposits.
AFRIKAANSE OPSOMMING: Diamiktiete is sedimentêre neerslae afkomstig vanaf verskillende omgewings en dit word meestal met n glasiale omgewing geassosieer. Alhoewel hierdie assosiasie nie in alle gevalle korrek is nie, word dit nog steeds gemaak as gevolg van die gebrek aan kennis om diamiktiete met selfvertroue te identifiseer, te klassifiseer en 'n afsettingsomgewing vir die sedimente te interpreteer. Gedurende die laat Karboon tot vroeë Permiese tydperk het twee diamiktiet afsettings gevorm gedurende die vorming van die Kaap Supergroep Kom en Karoo Kom in die suidelike grense van Suid-Afrika. Die afsetting staan bekend as die Miller diamiktiet en Dwyka diamiktiet. Laasgenoemde is redelik bekend en is gedurende die Karoo gletser ontvormings tydperk gesedimenteer. Die Dwyka diamiktiet word dikwels Dwyka Tilliet genoem, wat onvanpas is aangesien nie al die Dwyka neerslae direk gevorm het as gevolg van direkte glasiale kontak nie. Die oorsprong van die Miller diamiktiet is egter onseker. Dit word veronderstel dat die Miller diamiktiet óf deur 'n gletser, of puin vloei neerslag gevorm het in 'n deltaiese omgewing, dus word daarna verwys as 'n tilliet of ŉ diamiktiet. Om die sedimentêre omgewings van die twee bogenoemde diamiktiet afsettings in die studie area te bevestig, is twee fasies modelle aangebied met 'n voorkeur aan die tweede model. Die eerste fasies model verteenwoordig n siklus van ongebroke sedimentasie tydens die sluiting van die Kaapse Kom en die opening van die Karoo Kom. Die tweede fasies model verteenwoordig n hiatus tussen die afsetting van die bogenoemde komme. Gegrond op sy teksturele samestelling kan die Miller diamiktiet inderdaad as 'n diamiktiet geklassifiseer word. Beide diamiktiete (Miller en Dwyka) kan nie as tilliet neerslae beskou word nie, aangesien geen bewyse gelewer kan word van afsetting as gevolg van direkte glasiale kontak nie. Die Miller en Dwyka is n diamiktiet, maar is gevorm in verskillende afsettingsomgewings. Die Miller diamiktiet is 'n produk van die puin vloei neerslag vanaf die helling van ‘n delta, terwyl die Dwyka diamiktiet verteenwoordig ‘n afgeleë glasio-mariene “uit-reen” neerslae.

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44

Bath, Octavia. "Provenance of Siliclastic Sedimentary Rocks in the Eastern Portion of the North Caribou Greenstone Belt". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36115.

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The Zeemal Heaton Lake metasedimentary assemblage comprises ~50% of the eastern limb of the North Caribou greenstone belt, which hosts the Musselwhite gold deposit (~ 5.4 Moz Au). The metasedimentary assemblage is divided into two based on their distribution: the Central-belt and North-rim of the belt. The Zeemal Heaton Lake metasedimentary rocks have been interpreted to represent a turbidite succession, consisting of pelite, arkose, wacke and conglomerate. Detrital U-Pb zircon age populations from this study indicate variable sources in the Central-belt metasediments with a maximum age of deposition of 2798.8 ± 29 Ma, while metasediments along the North portion of the limb display a maximum age of deposition of 2696 ± 39 Ma. This indicates the likelihood of two discrete basins with the Zeemal Heaton Lake assemblage. Neodymium isotopic values for the sedimentary rocks along the North-rim of the belt display εNd2680Ma ranging from -1.2 to -0.9. An overlapping but slightly more evolved signature shown in the Central portion with values of εNd2800Ma -1.6 to 0.1. This indicates detritus for the Central-belt was likely sourced from the older (~2850 Ma), (tonalite-granodiorite) surrounding intrusions. The North-rim sediments were sourced (in part) from the younger (~2700 Ma) granitic intrusions and rhyolites. The surrounding batholiths display εNdt overlapping with North-rim sedimentary rocks, however, indicate significant contribution beyond these immediate surrounding batholiths, which may include older mafic (2982 ± 0.8, 2870 ±2 Ma), younger rhyolitic unit (2723 ± 2 Ma) or more distal sources than the intrusions immediately adjacent to the belt. Peak metamorphic mineral assemblages indicate a minimum of amphibolite facies-garnet zone or greater across the Central-belt portion of the greenstone belt. The North-rim metasediments display evidence for aureole metamorphism which may overprint earlier regional metamorphism. Nitrogen abundance and δ15N values of biotite of the Zeemal Heaton Lake metasedimentary assemblage indicate variable values than those associated with mineralization at the Musselwhite Mine, which is reported by Isaacs (2008). Mineralizing fluids from the Musselwhite mine have been interpreted by Issacs (2008) to be related to both metamorphic and magmatic fluids. Fluids associated with the Eyapamikama and/or Zeemal Heaton Lake metasediments appear to be metamorphic with minor magmatic influence near regional shear zones, but not directly related to the auriferous fluids which formed the Musselwhite mine.

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45

Papp, Matthias Laszlo. "A study of Neoproterozoic-Cambrian sedimentary rocks of the Nagur basin in Marwar, Rajasthan, India". Thesis, University College London (University of London), 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590576.

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46

Abdi, Hadj. "Mechanical and Hydromechanical Behavior of Host Sedimentary Rocks for Deep Geological Repository for Nuclear Wastes". Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/30924.

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Sedimentary rocks are characterized with very low permeability (in the order of 10-22 m2), low diffusivity, a possible self-healing of fractures, and a good capacity to retard radionuclide transport. In recent years, sedimentary rocks are investigated by many research groups for their suitability for the disposal of radioactive waste. Development of deep geologic repositories (DGRs) for the storage of radioactive waste within these formations causes progressive modification to the state of stress, to the groundwater regime, and to the chemistry of the rock mass. Thermal effects due to the ongoing nuclear activity can cause additional disturbances to the system. All these changes in the system are coupled and time-dependent processes. These coupled processes can result in the development of an excavation damaged zone (EDZ) around excavations. More permeable than the undisturbed rock, the EDZ is likely to be a preferential pathway for water and gas flow. Consequently, the EDZ could be a potential exit pathway for the radioactive waste to biosphere. An investigation of the Hydraulic-Mechanical (HM) and Thermal-Hydraulic-Mechanical-Chemical (THMC) behaviour of sedimentary rock formations is essential for the development of DGRs within such formations. This research work consists of (1) an experimental investigation of the mechanical behaviour of the anisotropic Tournemire argillite, (2) modeling of the mechanical behaviour of the Tournemire argillite, and (3) numerical simulations of the mechanical and hydromechanical behavior of two host sedimentary rocks, the Tournemire argillite and Cobourg limestone, for deep geological repository for nuclear wastes. The experimental program includes the measurements of the physical properties of the Tournemire argillite and its mechanical response to loading during uniaxial compression tests, triaxial compression tests with different confining pressures, unconfined and confined cyclic compression tests, Brazilian tests, and creep tests. Also, acoustic emission events are recorded to detect the initiation and propagation of microcracks within the rock during the uniaxial testing. The approach for modeling the mechanical behaviour of the Tournemire argillite consists of four components: elastic properties of the argillite, a damage model, the proposed concept of mobilized strength parameters, and the classical theory of elastoplasticity. The combination of the four components results in an elastoplastic-damage model for describing the mechanical behaviour of the Tournemire argillite. The capabilities of the model are evaluated by simulating laboratory experiments. Numerical simulations consist of: (1) a numerical simulation of a mine-by-test experiment at the Tournemire site (France), and (2) numerical simulations of the mechanical and hydromechanical behaviour of the Cobourg limestone within the EDZ (Canada). The parameters influencing the initiation and evolution of EDZ over time in sedimentary rocks are discussed.

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47

Hall, Dwight Lyman 1953. "Stratigraphy and sedimentary petrology of the Mesozoic rocks of the Waterman Mountains, Pima County, Arizona". Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/558034.

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48

Falck, Hendrik Carleton University Dissertation Geology. "Volcanic and sedimentary rocks of the Yellowknife Bay Formation, Giant Section, Yellowknife Greenstone Belt, NWT". Ottawa, 1990.

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49

Cullen, R. D. "Structural geology and metamorphism of archean volcanic and sedimentary rocks at Fenton Lake, Slave Province, N.W.T". Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5794.

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50

Haughton, David Lindsay. "The development and distribution of sedimentary rocks in the Rangal Coal Measures, South Blackwater, Central Queensland". Thesis, Queensland University of Technology, 1986. https://eprints.qut.edu.au/35984/1/35984_Haughton_1986.pdf.

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An investigation of the elastic interseam sedimentary rocks has elucidated the depositional and contemporaneous tectonic history of the Upper Permian Rangal Coal Measures at the C.S.R. South Blackwater Mine, Central Queensland, The studied section is stratigraphically bound by the Orion and Aries coal seams. The approximately 84 square km study area is located on the eastern flank of the Comet Ridge, within the Bowen Basin. The geological data used in this study consists of Qorehole information, approximately derived 2800 from bores, a geological and detailed database, containing examination of representative core material. The interseam sedimentary rocks indicate that deposition occurred within an upper mixed-load channels, delta plain environment, incorporating lacustrine (interchannel/interdistributary lakes), fluvio-lacustrine (crevasse splay/minor suspended-load channels. deltas), and Normal faults occurred contemporaneously with the accumulation of the Castor Seam. These faults displaced the sequence underlying the Castor Seam and modified subsequent deposition. The faults also show brittle deformation due to post-lithification tectonism. Split and/or absent coal in the Castor Seam displays a close association with faults, which disrupt the Pollux Seam. Such locations can be used as primary drilling targets during the delineation of faults and the definition of fault-free mining blocks.

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