Thesis (Ph. D.)--University of Texas at Austin, 2003. / Available also in an electronic version.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1952. / Typescript. Two folded charts in pocket. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 83-87).

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Quad 9 of the U.K.C.S., North Sea is located 215 miles NE of Aberdeen. It contains four producing fields with over 400 mmbbls of oil and NGL's and 5.1 TCF of gas initially in place. The major reservoir unit is the Middle Jurassic (Bajocian to Bathonian) Beryl Formation, a marginal to shallow marine deposit which varies in thickness from 150' to 1100' across the studied area. It was deposited within the Beryl Embayment, a transfer zone between two actively extending basin bounding faults of the South Viking Graben, prior to the onset of the major rifting phase during the Callovian to Ryazanian. The objectives of the thesis were to provide a revised sedimentological model for the area accounting for the contrasting sedimentary styles present within the Beryl Formation and to unify the different correlation schemes used by the different operating companies in the area. It was based on well data from 58 cored and a further 79 uncored sections spreading nine licence blocks within Quad 9. Reservoir engineering, biostratigraphic and structural data has also been used for a fully integrated study. Initial core logging identified 32 facies and 10 trace fossil assemblages which were subsequently integrated into 14 facies associations. These were then extrapolated further into the uncored sections by wireline facies associations. Correlation was initially driven by comparison of cored sections but finalised by an integration of the reservoir engineering and biostratigraphic data. Outcrop work on the Middle Jurassic of Skye and Companian of eastern Utah provided an analogue study to accompany the downhole data. Quad 9 can be split up into three main areas distinguished by different stratigraphic histories, the southern area consisting of the Buckland and Sorby Fields, the central area consisting of the Beryl, Nevis, Ness and Linnhe Fields and a northern area consisting the Bruce and Keith Fields.

A Bacia Bauru formou-se no Cretáceo Superior (Coniaciano-Maastrichtiano), por subsidência termo-mecânica, na parte centro-sul da Plataforma Sul-Americana. Esta bacia, continental interior, acumulou uma seqüência sedimentar essencialmente arenosa (atualmente com espessura máxima de quase 300 m), que ocorre em área de cerca 370.000 km². Tem por substrato rochas vulcânicas da Fm. Serra Geral (Ki), sobretudo basaltos, da qual é separada por superfície erosiva regional. A área investigada corresponde à parte oriental da Bacia Bauru (oeste de São Paulo, Triângulo Mineiro e noroeste do Paraná), situada entre as coordenadas 18° S e 25° S; e 47° W e 55° W, com cerca de 180.000 km². O presente estudo discute a estratigrafia e a evolução sedimentar daquela área, mediante análise de sistemas deposicionais - baseada em levantamentos de campo - e ensaios com amostras em laboratório (microscopia óptica, microscopia eletrônica de varredura com EDS, e difração de raios X). Segundo a distribuição das associações de fácies e suas relações encontradas é proposta uma revisão estratigráfica para a parte oriental da Bacia Bauru. Nesta área, a seqüência neocretácea foi dividida em dois grupos parcialmente cronocorrelatos: Caiuá (formações Rio Paraná, Goio Erê e Santo Anastácio) e Bauru (formações Uberaba, Vale do Rio do Peixe, Araçatuba, São José do Rio Preto, Presidente Prudente e Marília, mais os Analcimitos Taiúva). A sedimentação na Bacia Bauru ocorreu em duas fases principais, a primeira em condições essencialmente desérticas, a seguinte com maior presença de água, ainda que em clima semi-árido. As associações de fácies da primeira fase correspondem, em termos litoestratigráficos, a depósitos de: lençóis de areia com campos de dunas baixas, loesse e wadis (Vale do Rio do Peixe); lençóis de areia secos (Santo Anastácio); dunas eólicas médias e interdunas úmidas, zona periféricas de sand sea (Goio Erê); e complexos de dunas eólicas de grande porte (draas), parte central de sand sea interior (Rio Paraná). As associações da segunda fase correspondem a depósitos de: rios entrelaçados, de baixa a média sinuosidade (Uberaba); pantanal interior (Araçatuba); zonas distais de leques aluviais (Echaporã); sistema fluvial entrelaçado, partes medianas de leques aluviais (Serra da Galga); sistema fluvial entrelaçado, partes medianas de leques aluviais (Ponte Alta); sistema fluvial entrelaçado arenoso (São José do Rio Preto); e sistema fluvial meandrante arenoso fino, de canais rasos (Presidente Prudente). A primeira corresponde ao sepultamento progressivo do substrato basáltico por extensa e monótona manta arenosa, formada principalmente por depósitos de lençóis de areia, com pequenas dunas e estratos de loesse. Desta fase, os raros depósitos fluviais preservados correspondem a fluxos de enxurradas de deserto (wadis). A intensificação das atividades tectônicas nas bordas norte-nordeste e leste, e provavelmente na borda noroeste, provocaram significativa mudança no quadro paleogeográfico da bacia, promovendo o avanço de leques aluviais para o seu interior. Ao mesmo tempo, mudanças climáticas graduais trouxeram maior umidade às zonas marginais. Tais alterações assinalam o início da segunda fase de sedimentação, em que se desenvolveram sistemas fluviais importantes, de nordeste para sudoeste, entre as bordas e o deserto interior. O clima quente e seco determinou a manutenção de condições desérticas no interior da bacia, desde o início até a segunda fase de sedimentação. Durante a elevação das bordas houve a instalação de diversos corpos de rochas alcalinas nos altos marginais, magmatismo extrusivo próximo da borda leste (analcimitos Taiúva) e silicificação localizada, no sul da bacia. A nova moldura, realçada na passagem entre as fases I e II, corresponde a charneiras de importantes altos tectônicos marginais. O trato de sistemas desértico é formado pelas formações Vale do Rio do Peixe, Santo Anastácio, Goio Erê e Rio Paraná. O relevo original do substrato criou condições endorrêicas em zona interior da bacia, determinando a formação de uma grande área pantanosa em clima semi-árido (Pantanal Araçatuba), no início da sedimentação neocretácea. O soerguimento das margens norte e nordeste provocou modificações na paleogeografia da bacia. Talvez o mais importante tenha sido o embutimento - pós-sedimentação - da faixa do Triângulo Mineiro onde hoje ocorre a Fm. Uberaba (depressão de Uberaba). Os fluxos fluviais distais de leques aluviais do Mb. Serra da Galga, posteriores a este evento, apresentavam persistentes rumos para noroeste, possivelmente por influência de barreiras internas então criadas. Os fluxos fluviais entrelaçados do Mb. Serra da Galga avançaram sobre a Fm. Uberaba, soterrando-a. Os influxos de material originados em leques aluviais marginais foram gradualmente transformados, bacia a dentro, em sistemas fluviais entrelaçados e depois em meandrantes, até a sua desarticulação na periferia do deserto Caiuá. Os fluxos fluviais provenientes da parte nordeste alcançavam o interior da bacia em sistemas entrelaçados arenosos (Fm. São José do Rio Preto), de rumo geral sudoeste, muito constante. À medida que adentravam a bacia, a paisagem tornava-se cada vez mais plana, e os sedimentos transportados cada vez mais finos. Assim, devido ao baixo gradiente da bacia, nas porções distais este sistema fluvial tornava-se meandrante, ainda arenoso, com canais mais estáveis, definidos e rasos (Fm. Presidente Prudente). Serpenteavam em extensas planícies aluviais, entre lagoas residuais formadas sobretudo após eventos de transbordamento. Os arenitos e arenitos conglomeráticos dos membros Serra da Galga e Ponte Alta correspondem portanto às fácies proximais das associações fluviais São José do Rio Preto e Presidente Prudente. O aumento da aridez rumo ao interior determinava progressivo aumento da evaporação e escassez de água no ambiente, até o desaparecimento do sistema fluvial nas planícies arenosas. As unidades de origem eólica exibem notável constância do sentido de transporte, durante a sedimentação da seqüência neocretácea. O padrão geral de fluxos fluviais aponta para o interior da bacia. Os resultados obtidos para o Mb. Serra da Galga, entretanto, são claramente discordantes. Admitindo-se que esta unidade corresponde às porções proximais do sistema São José do Rio Preto-Presidente Prudente, supõe-se que tenha existido uma barreira geográfica na borda nordeste da bacia, associada às transformações tectônicas ali ocorridas, que teria determinado a passagem dos fluxos fluviais rumo ao interior da bacia, mais para oeste. O estabelecimento do Pantanal Araçatuba, subambiente peculiar criado no estádio inicial, provavelmente decorre da posição topográfica mais baixa original do substrato naquela região. O limite oeste da área de ocorrência atual da Fm. Araçatuba corresponde a uma feição elevada do substrato basáltico (soleira de Jales-Andradina). O aporte continuado de sedimentos eólicos, que inicialmente supriu dunas e lençóis de areia marginais ao charco, terminou por soterrar a depressão original. Todas as ocorrências fossilíferas conhecidas na bacia localizam-se na sua parte oriental e refletem o controle essencialmente paleogeográfico. Compreendem restos ósseos, sobretudo de répteis - crocodilos, quelônios e dinossauros -, anfíbios, peixes, moluscos, crustáceos e oogônios de algas carófitas. Em geral, predominam ocorrências vinculadas a litofácies de origem fluvial, com remobilização e transporte de material, do que decorre rara preservação de esqueletos completos. As principais ocorrências estão em depósitos de planícies fluviais de transbordamento e lagoas efêmeras (no interior da bacia) e naqueles vinculados a fluxos aquosos entrelaçados e a lagoas de zonas de leques aluviais marginais da bacia. No interior mantiveram-se, durante os dois estádios de sedimentação, condições desérticas quentes, motivo da escassez e baixa diversidade das ocorrências. A fossilização ocorreu quase sempre com perfeita preservação da estrutura óssea e manutenção da natureza fosfática original, independente das litofácies ou unidades geológicas de origem. Os ossos são constituídos por fluorapatita de baixa birrefringência, com laminação concêntrica, canais haversianos e camadas fibrosas, similares às estruturas de ossos dos vertebrados atuais. Não foram verificadas deformações mecânicas após o soterramento, provavelmente devido ao baixo grau de diagênese a que foram submetidas as rochas, além da proteção fornecida pela cimentação carbonática precoce, presente em muitos casos. Este cimento ocorre freqüentemente associado, permineralizando ou substituindo parcialmente a estrutura orgânica. Algumas vezes os espaços internos estão preenchidos por material clástico. Nos compartimentos paleoecológicos mais interiores da bacia (São José do Rio Preto e Presidente Prudente) a grande maioria dos restos fósseis é constituída por ossos fragmentados e/ou desarticulados, concentrados em fácies de barras de canais rasos ou wadis. Por outro lado, nos jazigos fossilíferos da região de Peirópolis, situados próximos da borda da bacia, são encontrados ossos de vertebrados em melhor estado de preservação. Sem dúvida, a maior disponibilidade de água favoreceu o florescimento e a manutenção da fauna e flora nas regiões marginais, em lagoas de planícies de inundação e corpos aquosos formados entre leques aluviais coalescentes. Os restos ali encontrados sofreram, assim como os do Mb. Echaporã, menor transporte antes do soterramento. Nestas regiões, a maior porosidade dos sedimentos e a maior disponibilidade de águas ricas em carbonatos, propiciou intensa cimentação dos ossos, sendo neles comuns as feições de rompimento por crescimento expansivo (displacive) de calcita. Três tipos principais de cimentação carbonática foram identificados na parte leste da bacia: pedogenética, subterrânea e diagenética; de ordem temporal aproximadamente definida, porém com freqüente sobreposição de eventos, dependendo da vulnerabilidade dos depósitos em relação aos sucessivos processos de dissolução e reprecipitação no decorrer do tempo. Os calcretes do Mb. Ponte Alta preservam claras feições de gênese associada a fluxos rasos de águas subterrâneas. Por outro lado, os calcretes pedogênicos do Mb. Echaporã são registros inequívocos de formação por processos edáficos. Nas outras unidades, em geral mais interiores, portanto originalmente menos cimentadas, a remobilização diagenética parece ter sido o principal processo transformador registrado. De modo geral, todas as associações litofaciológicas da parte oriental da Bacia Bauru apresentam algum vestígio de atividades biológicas e/ou de processos edáficos. Os melhores exemplos de formação de calcretes pedogenéticos são encontrados no Mb. Echaporã. Dentre os vestígios de raízes identificados são comuns os contra-moldes, caracterizados como túbulos preenchidos por material distinto do arcabouço (arenito ou siltito, cimentados ou não). Moldes de raízes foram encontrados, em geral, em litofácies mais finas, associadas a ambientes de maior umidade (pântano, lagoas ou planícies de inundação). A análise das seções delgadas permitiu ainda reconhecer vestígios de processos pedogenéticos de dois tipos: autóctones (encontrados em amostras do próprio horizonte edáfico) e alóctones (partículas e fragmentos líticos de origem edáfica, removidos e acumulados em litofácies de maior energia, como na base de estratos cruzados de barras arenosas ou em depósitos residuais de canal fluvial). / The Bauru Basin was formed in the Upper Cretaceous (Coniacian-Maastrichtian) as a result of the thermo-mechanical subsidence of the central-southern part of the South-American Platform. This inner continental basin spreads over an area of approximately 370,000 km² and is filled by a sandy sequence with maximum thickness of 300 meters at present. Its substratum is constituted by volcanic rocks (mainly basalts) of the Serra Geral Fm. (Kl) from which it is separated by a regional erosive surface. The area examined in this research corresponds to its eastern part of the basin (west of São Paulo, southwest of Minas Gerais, northwest of Paraná), with about 180,000 km², and is located between the coordinates 18°S to 25° S and 47° W to 54° W. This research deals with stratigraphy and sedimentary evolution of the Bauru Basin through analysis of the depositional systems, based on fields data and mineralogical, petrographic and microchemical evaluation (optical microscopy, scanning electron microscopy with EDS, X-ray diffractometry) of significant samples. Based on the distribution and interrelations of facies associations a stratigraphic revision is proposed for this part of the basin. In this area the neocretaceous sequence is now divided in two groups, partially contemporaneous: Caiuá Gr. (Rio Paraná, Goio Erê and Santo Anastácio formations) and Bauru Gr. (Uberaba, Vale do Rio do Peixe, Araçatuba, São José do Rio Preto, Presidente Prudente, and Marília formations, with the Taiúva analcimites). Sedimentation in Bauru Basin occurred in two main phases: the first in an essentially desertic environment, the second with more water available, but still under semi-arid conditions. The facies associations of the first depositional phase correspond, in lithostratigraphic terms, to the following deposits: sandsheets with low dune fields, loess and wadi deposits (Vale do Rio do Peixe Fm.); dry sandsheets (Santo Anastácio Fm.); medium sized dunes and humid interdunes from peripheral zones of sand seas (Goio Erê Fm.); complex of large sized eolic dune (draas), corresponding to the central part of an inland sand sea (Rio Paraná Fm.). The associations of the second phase correspond to: braided river system of low to medium sinuosity (Uberaba Fm.); inland swamps (Araçatuba Fm.); distal parts of aluvial fans (Echaporã Mb.); braided fluvial system, medium parts of alluvial fans (Ponte Alta and Serra da Ganga members); braided sandy fluvial system (São José do Rio Preto Fm.); meandering fluvial system with fine sandy deposits of shallows channels (Presidente Prudente Fm.). The first depositional phase corresponds to the progressive burial of the basaltic surface by widespread and homogeneous sandy blanket, formed mainly of sand sheets, with small dunes (wadis). The intensification of the tectonic activities at the north-northeastern and eastern margins, and probably also at the northwestern margin, caused significant changes in the paleogeographic conditions of the basin, promoting inward progression of the alluvial fans. At the same time, climatic changes increased the humidity level in the marginal zones. These changes mark the beginning of the second sedimentary phase, during which important fluvial systems were established between the marginal zone and the inland desert from northeast to southwest. The hot and dry climate determined the maintenance of desertic conditions in the interior of the basin during most of the sedimentation time. During the uplift of the margins, several alkaline magmatic bodies intruded into the marginal zones, causing extrusive magmatism near the eastern border (Taiúva analcites), as well as localized silicification in the southern border. This new frame corresponds to the hinge of important marginal tectonic heights. The formations Vale do Rio do Peixe, Santo Anastácio, Goio Erê and Rio Paraná constitute the systems deposited in the desertic environment. The original relief of the basaltic rocks favored the formation of an endorrheic drainage system in the interior of the basin, causing the appearance of a large swampy area under semi-arid climate (Araçatuba Swamp), in the beginning of the sedimentation cycle. The uplift of the northern and northeastern margins had a large influence on the paleogeography and in the basin sedimentar record, the most important being the postdepositional development of the Uberaba depression in the eastern part of the Triangulo Mineiro, where part of the Uberaba Fm. was preserved. The river flows of distal parts of alluvial fans (Serra da Galga Mb.) show steady shift to northwest, possibly due to geographic barriers. The braided river sedimentation of the Serra da Galga Mb. moved over the Uberaba Fm., causing its burial. The marginal alluvial fans gradually transformed in braided fluvial systems, evolving to meandering systems in the interior of the basin, that deteriorated in the vicinities of the Caiuá Desert. The alluvial fans coming from the northeastern part of the basin reached its interior as braided sandy systems (São José do Rio Preto Fm.), with a general and very constant southwestern direction. Toward its interior the basin topography became flatter, and the deposited sediments, finer. Due to the low relief of the basin, this fluvial system became meandering in its distal portions, with more stable and defined but shallow channels filled with sandy sediments (Presidente Prudente Fm.). The rivers flowed through wide alluvial plains, among lagoons formed mainly after flood events. The sandstones and conglomeratic sandstones of the members Serra da Galga and Ponte Alta represent accordingly the proximal facies of the fluvial sediments São José do Rio Preto and Presidente Prudente. The increasing aridity towards the interior of the basin caused the deterioration of the fluvial system in the sandy flats. The eolic sediments show a remarkable persistence of the transportation direction during the sedimentation of the neocretacic sequence. The general pattern of the fluvial flows is directed toward the interior of the basin. The data from the Serra da Galga Mb. are, however, clearly discordant. Supposing that this unit represents the proximal facies of the system São José do Rio Preto-Presidente Prudente, the existence of a topographic barrier in the northwestern part of the basin can be inferred, which must have determined the direction of the fluvial flow westwards, to the interior of the basin. The development of the Araçatuba Swamp, a peculiar sub-environment of the beginning of the depositional history of the Bauru Basin, was probably a consequence of the originally lower topographic position of the basin substratum in that region. The western limit of occurrence of the Araçatuba Fm. corresponds to a height of the basaltic substratum (Jales-Andradina Height). The constant arrival of material transported by the wind, which initially formed dunes and sandsheets marginally to the swamp, eventually buried the original depression. All known fossil occurrences in this basin are located in the eastern part of the basin and were controlled mainly by the paleogeography. They comprise bone remains, mainly from reptiles-crocodiles, turtles, dinossaurs -, as well as amphibians, fishes, mollusks, crustaceans, and oogones of charophytic algae. These fossils were originally deposited in a fluvial environment, with subsequent remobilization and transportation of the pieces, resulting in very scarce preservation of complete skeletons. The main occurrences are from deposits of fluvial flood plains and ephemeral lagoons in the interior of the basin, as well as from those of braided water flows and lagoons located in zones of marginal alluvial fans. In the interior of the basin the hot desertic conditions prevailed during the two phases of sedimentation, causing great scarcity and lack of variety of occurrences. The fossilization process led mostly to the perfect conservation of the bone structure and maintenance of the phosphoric material, independant of which the original depositional lithofacies or geological unit. The bones are constituted of fluorapatite with low birefringence, presenting concentric lamination, haversian channels and fibrous layers, similar to the bones structure of present day vertebrates. No post-burial mechanical deformations could be detected, probably due to the low degree of diagenesis of the sediments and the protection by the carbonatic cementation, present in many cases. This cement is frequently associated to the organic structure, in form of mineralization or partial substitution of the organic material. Sometimes the internal voids are filled with clastic material. In the innermost paleoenvironments of the basin (São José do Rio Preto and Presidente Prudente) the great majority of the fossil remains is constituted of bone fragments or disarticulated pieces, accumulated mainly in bars facies of shallow channels or wadis. On the other side, in the fossiliferous levels in the region of Peirópolis, near the border of the basin, the bones are better preserved. The greater water availability in the marginal areas surely favored the existence and maintenance of the fauna and flora in flood plain lagoons and water bodies occurring between coalescing alluvial fans. The remains found in these sediments (as well as those found in the Echaporã Mb.) were subjected to less transport before burial. In these regions the higher porosity of the sediments and the greater availability of carbonate-rich waters led to intense cementation of the bones, often causing disruptive patterns due to the displacive growth of calcite. The main carbonate cemented materials types could be identified in the eastern part of the basin: crusts and nodular levels of pedogenetic origin, ground water calcretes, and diagenetic cemented sandstones. Their time sequence of the formation is roughly defined, but frequent superposition of events ocurred, controlled by the accessibility of the deposits to successive processes of dissolution and reprecipitation. The calcretes of the Ponte Alta Mb. show clear features linked to the genesis due to shallow groundwater. On the other side, the pedogenetic calcretes of the Echaporã Mb. are unmistakable records of genesis through the action of edaphic processes. In other more interior units, originally less cemented, the diagenetic mobilization seems to have been the main transforming process. Generally, all lithofacies associations in the eastern part of the Bauru Basin present some vestiges of biological activities and/or edaphic processes. The best examples of the formation of pedogenetic calcretes are found in the Echaporã Mb. Among the identified vestiges of vegetable roots, the countermoulds are very common, characteristically occurring as tubules filled with material other than the surrounding rocks (sandstone or siltistone, cemented or not). Root moulds were generally found in finer lithofacies deposited in wetter environments (swamps, lagoons or flood plains). The analysis of thin sections allowed the recognition of two types of pedogenetic features: autochtonic (found in samples of the same edafic horizon) and allochtonic (found as particle and lithic fragments of edaphic origin, transported and accumulated in lithofacies of higher energy, for instance in the base of cross beds or in residual deposits of river channels).

The fossil record is the only direct source of data for studying modes (patterns) and rates of morphological change over geologic time periods. Determining modes is critical for understanding macroevolutionary processes, but just how modes can vary within a taxon, and why, have hitherto been largely understudied. To address this, I examined patterns of morphological change in the shell of the Mesozoic marine bivalve genus Buchia over its geographic and temporal range. Buchia was chosen as a test subject because it is abundant, well-preserved across a variety of facies, and is widely distributed across the Northern Hemisphere where the likelihood of multiple lineages is low. While the focus of this thesis is on evolutionary patterns, it is also necessary to address issues of taxonomy and geographical variation, making this research applicable to a wide-variety of fields. Previous to this study there was no protocol for measuring buchiid valves, nor was the genus studied in a quantitative manner. Throughout this research I used ten morphological characters to describe shell shape and size. Multivariate methods (principle component and canonical variate analyses) were employed to discriminate between species of Buchia and examine how morphological characters change through time and space within the genus. Evolutionary patterns were delineated using two well-established programs that discriminate between multiple modes of evolution. Overall, nearly 2000 specimens from eight geographical locations around the world were studied for this thesis. I found the genus Buchia was a useful tool for evolutionary studies as it can be studied quantitatively in space and time. Specically I have found that buchiid species can be delineated using morphometrics; the genus is restricted to the Northern Hemisphere; while the environment significantly affects morphology, there is no evidence of a latitudinal gradient; diversity and disparity within Buchia are not correlated; most evolutionary modes conformed to random walks or stasis; and modes and rates vary across the geographical range of the genus. Overall, I have found that the environment plays an important role in shaping both morphology and modes. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

No description available.

The Peterborough Drumlin Field in southern Ontario, Canada (PDF; Crozier 1975, Karrow 1981, Boyce and Eyles 1991) is a well-documented and extensive drumlin field that hosts many communities dependent upon groundwater resources. Population growth in the area and concerns for the long-term sustainability of these resources has prompted considerable interest in determining the location, extent and potential productivity of subsurface aquifers in the region. The origin of the drumlins within the PDF is still widely debated, despite many years of study, and there is little understanding of the nature, geometry, and connectivity of aquifers within the Quaternary-age sediments beneath the drumlins. This study involves detailed analysis of sedimentological data available from water well logs from selected drumlins and adjacent low areas (swales) in the PDF. These data are used to investigate the subsurface stratigraphy of the drumlins, contribute to the understanding of drumlin formation, and establish hydrogeological characteristics of drumlins within the PDF. A relatively consistent subsurface stratigraphy can be identified in the studied drumlins consisting of patchy units of sand and gravel overlying a southward sloping bedrock surface, a thick diamict (till) package containing discontinuous coarse-grained sand and gravel units, and surface veneers of sand, silt or clay in low areas (swales) between drumlins. This subsurface stratigraphy can be traced between drumlins and adjacent swales and suggests that the drumlins within the PDF formed largely as a result of subglacial erosion of pre-existing sediment. Two major aquifers can be identified beneath the PDF from the water well records; one is a basal aquifer within fractured bedrock and overlying coarse-grained sands and gravels, and the second (upper aquifer) is formed by the discontinuous zone of sands and gravels within till. These coarse-grained interbeds within the till allow it to function as a ‘leaky aquitard’ and produce groundwater flow pathways that are not easy to predict, may not be high-yielding, and may be susceptible to anthropogenic sources of contamination; these characteristics will likely prevent further development of this aquifer for multi-user (communal) water supply. The Hiawatha First Nations (HFN) community is located within the Peterborough Drumlin Field and has been attempting to find a more sustainable, and possibly communal, groundwater supply in the drumlizined terrain. Examination of lithological and hydrogeological data from water well records together with information obtained from four recently drilled on-site wells allowed for a detailed analysis of the till stratigraphy within this portion of the drumlin field. The stratigraphy identified at this site is consistent with that identified elsewhere in the PDF and a basal bedrock aquifer and an upper discontinuous Quaternary aquifer can be discriminated. It is recommended that the HFN community continue to upgrade/maintain individual private wells in the discontinuous upper aquifer and utilize the basal bedrock aquifer for developments that require greater water yields. This study provides insight into the subsurface stratigraphy that may be found beneath drumlins in an extensive drumlin field and may help in determining the origin of these enigmatic landforms. Enhanced understanding of the hydrogeological characteristics of Quaternary-age sediments underlying drumlin fields will assist in the development of appropriate exploration, protection, and remediation strategies for valuable groundwater resources. / Thesis / Master of Science (MSc)

Deep-marine basins linked to active continental margins by sloped ocean-floor profiles commonlyhost the final accumulation of sediment that was eroded and transported from the continents. Thedeep-marine sediment archives preserved in these settings commonly offer the most completerecord of sediment transfer from continents to ocean basins over geologic time scales. This isespecially true in basins associated with regions of active tectonism, where loss or alteration ofsediment source terrains leave submarine basin deposits as the only record of the tectonic and cli-matic forcings that govern the transfer of sediment to the deep basin. The overarching goal of thisdissertation is to evaluate controls on submarine slope and basin-floor sedimentation that considersboth large-scale system drivers and the internal complexities and autogenic processes associatedwith sediment routing systems. In pursuit of this goal, the research presented in this dissertationspans a range of spatial and temporal scales. At the largest scale, the influence of sediment recy-cling is addressed to evaluate how changes in intrabasinal sediment sources reflect phases of basinevolution and what influence recycling of previously deposited basin sediments has on the fidelityof the deep-marine sedimentary record at geologic time scales. At the smaller scale, analysis ofsedimentation units and characterization of sedimentary bodies form the foundation for linkingthe stratigraphic preservation of depositional processes to discrete submarine geomorphic condi-tions. Such a linkage can provide insight into changes in slope gradient and the transition fromsediment transport and bypass to sediment deposition along the slope profile. Thirdly, a detailedinvestigation of deformed slope deposits addresses how depositional processes and stratigraphicstacking of submarine fan deposits influences slope stability. Synthesis across these broad spatialand temporal scales required integration of various tools and data types including: (1) detailedoutcrop measurements, (2) cliff-face correlation and characterization of depositional architecture,(3) geologic mapping, (4) basin-scale correlation, (5) detrital geochronology, and (6) carbonategeochemistry. / Ph. D.

The Cowlitz Formation in southern Columbia and Clatsop counties, northwest Oregon was studied in order to prepare a geologic map of parts of this formation and to determine the character of its lithofacies and the environments of deposition.