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Fine-grained clastic sediments make up the gross lithology in interior basins of ancient epicontinental seas, such as the Cretaceous Western Interior Seaway. This study provides a high-resolution thin-bedded facies analysis and regional correlations to determine how the heterolithic units of the Juana Lopez Member of the Mancos Shale were transported and deposited in the San Juan Basin. Data for this study was obtained from outcrop observations in eleven measured sections, spanning a distance of 115 kilometers. Eleven facies are observed, four sequences and eleven parasequence sets are identified. A depositional model is determined through the high-resolution facies analysis, which suggests deposition on a proximal to distal mudbelt through multiple processes, including turbidity currents, hypopycnal plumes, wave enhanced sediment gravity flows (WESGFs), storm surges, tides and oceanic currents. Overall, the Juana Lopez is dominated by upward-shoaling parasequence sets, with an increasing number and thickness of sandstone dominated bedsets, suggesting regressive sedimentation with distal expressions of transgression found in two parasequence sets. The source of sediment is determined through 520 paleocurrent measurements and plaeogeographic data, and is determined to be transported by along-shelf currents, dominantly from proximal NE clastic wedges. / Thesis / Master of Science (MSc)

The quantification of sediment budget in a well-defined ancient source-to-sink (S2S) system is vital to understand Earth history and basin evolution. Fulcrum analysis is an effective approach to estimate sediment volumes of depositional systems, given total mass balance throughout source areas to basins. The key to this approach is to quantify sediment in a closed S2S system with time controls. We analyzed Allomember E of the Cretaceous Dunvegan Alloformation in the Western Canadian Sedimentary Basin to test this sediment estimation approach. The results indicate that the sediment transported by the trunk-river generically matches the sediment estimated to be deposited in the basin. The upper-range estimate may suggest mud dispersal southward by geostrophic currents. Deciphering the relationships between traditional lithostratigraphy and sequence stratigraphy is the key to correctly understanding time-stratigraphic relationships. High-resolution sequence stratigraphic analysis of the Cretaceous Gallup system documents the high-frequency depositional cyclicity using detailed facies analysis in extensively exposed outcrops in northwestern New Mexico, US. We identified thirteen stratigraphic sequences, consisting of twenty-six parasequence and sixty-one parasequences. Shoreline trajectories are evaluated based on the geometry of the parasequences. The results show the previously identified sandstone tongues are equivalent to high-frequency sequence sets. The depositional duration estimates of respective sequence stratigraphic units, associated with the estimated changes in relative sea level, imply that Milankovitch-cycle-dominated glacio-eustasy may be the predominant control on the high-frequency sequence stratigraphy. Shoreline processes are more dynamic and complicated with mixed-energy dominance. The re-evaluation of the depositional environments of the Gallup system and the reconstructions of the paleogeography with temporal controls help to examine the depositional evolution in space and time. Paleogeographic reconstructions at parasequence scales allow for the documentation of the process-based lateral facies variations and the depositional evolution. The distinction between different wave-dominated facies associations is proposed based on this process-based facies analysis. / Dissertation / Doctor of Philosophy (PhD)

Well-cuttings data and wireline logs in conjunction with limited core and outcrop data are used to generate a regional, three dimensional high resolution sequence framework for Upper Mississippian (Chesterian), Big Lime carbonates, West Virginia, U.S.A.. The analysis was done using the washed coarse fraction (1-2 mm) of cuttings for each sample interval, which were separated into Dunham rock types, counted to determine relative abundance and the data presented as percent lithology plotted against depth for each well. Digitized wireline logs and the cuttings-percent logs were slipped to take into account drilling lag and lithologic columns produced from the combined data. Sequence stratigraphic cross sections through the basin and into the outcrop belt, with a resolution of 10 feet were then produced. Sequence stratigraphic time slices were generated as isopachs maps of the sequences, and of lowstand-transgressive, and highstand tracts with major facies shown. This data was then used to document the stratigraphic response of the foreland basin to tectonics and, with isotope data from the slope section, evaluates evidence for glacio-eustasy during the transition into ice-house times. The major mappable sequences are fourth-order sequences, a few meters to over 90 meters (300 feet) thick. They consist of updip red beds and eolianites, lagoonal muddy carbonates, ooid grainstone and skeletal grainstone-packstone shoal complexes, deeper ramp and slope wackestone-mudstone, and laminated argillaceous lime mudstone. Maximum flooding surfaces on the ramp slope occur at the base of deeper water facies that overlie lowstand- to transgressive siliciclastic or carbonate complexes, whereas on the ramp, maximum flooding surfaces cap near-shore shale or lime mudstone beneath widespread grainstones. The highstand systems tracts contain significant grainstone units, interlayered with extensive lagoonal lime mudstones. In spite of differential subsidence rates across the foreland, fourth-order eustatic sea level changes documented by isotopic signals in basinal facies, controlled regional sequence development. Thrust-load induced differential subsidence of fault-blocks of the foreland basement controlled the rapid basinward thickening of the depositional wedge while subtle structures such as arches at high angles as well as parallel to the margin, affected thicknesses and facies development. / Ph. D.

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The sedimentary facies of the Upper Silurian and Lower Devonian Madrid, Carrabassett, and Seboomook Formations, exposed on the northwestern limb of the Kearsarge-Central Maine Synclinorium, belong the following facies categories: (1) sandstone-rich turbidites, (2) pelitic turbidites and related hemipelagites, and (3) disrupted facies. Lithofacies within each formation are organized into one or more descriptive facies associations--these are the: (1) massive sandstone, (2) thickbedded turbidite, (3) thin-bedded turbidite, (4} chaotic, (5) massive-pelite, and (6) laminated-pelite facies associations. Where strata are well exposed, and sedimentary structures and bed geometries are discernible, these descriptive facies can be discussed in terms of one or more interpretive associations (e .g. channel and channel-margin facies associations.) The Devonian Carrabassett Formation is the youngest widespread formation exposed in the Kearsarge - Central Maine Synclinorium. In the Jo-Mary Mountain quadrangle and surrounding area, the Carrabassett Formation is a complex facies assemblage dominated by fine-grained turbidite and chaotic facies. The underlying Upper Silurian Madrid Formation is composed largely of sandstone- and siltstone-rich turbidites. The younger Seboomook Formation is characterized by pelitic turbidite and related hemipelagic facies. A facies analysis of the Carrabassett and underlying Madrid Formations indicates that sediments were derived from eastern sources and deposited in northwesterly-migrating slope and foredeep environments during the Late Silurian and Early Devonian. Sedimentation is believed to have been partly diachronous, becoming progressively younger toward the northwest. Short term penecontemporaneous deposition probably occurred in different settings, such as along the axis of the foredeep basin (Madrid Fm.) and lower- to base-of-slope environment (Carrabassett Fm.). Olistostromes, shed from the lower slope, and thir bedded turbidites dominated later stages of basin sedimentation when the source of coarse clastics, supplied from the northeast, was shut off during the Early Devonian. These environments are interpreted in terms of an accretionary complex contemporaneous with initial stages of compression during the Acadian orogeny. / 2999-01-01

Vertebrate fossils have been discovered at several locations in the Bighorn Basin (Wyoming). The Virginia Museum of Natural History's (VMNH) digsite is located in the eastern part of the Bighorn Basin, in the Coyote Basin. Many scientists have worked within these basins trying to describe the stratigraphy. One question specifically asked is where the boundary between the Morrison Fm. (Jurassic) and the Cloverly Fm. (Cretaceous) lies. This new study attempted to show if the current method (Kvale, 1986) of determining the boundary is appropriate. The stratigraphy of the area was examined using Kvale, 1986, Ostrom, 1970, and Moberly, 1960's work in order to see which model was more robust. The fossils in the VMNH digsite were used to supplement the stratigraphic data in determining the age of specific beds. All of Ostrom's units were identified throughout the study area. There is some doubt as to whether the units would be acceptable outside of the Coyote Basin because of laterally discontinuity. Nevertheless, his description of units is satisfactory for the study area, and is more appropriate than other methods. The geologic age of the dinosaurs uncovered in the VMNH quarry is in agreement with the age determined stratigraphically. The VMNH site is below Ostrom's Unit II, which would place it in the Late Jurassic. The determination of the Jurassic/Cretaceous stratigraphic boundary has not been resolved. However, since the Pryor Conglomerate member of the Cloverly Fm. can be identified throughout this area, it is proposed as the Morrison Fm./Cloverly Fm. boundary. / Master of Science

O Subgrupo Itararé apresenta o registro sedimentar mais expressivo da glaciação que assolou a Bacia do Paraná durante o Neopaleozóico. Próximo à borda leste da bacia, em especial na área do estudo, entre os municípios de Sorocaba e Itapetininga, este registro é caracterizado basicamente por depósitos glaciomarinhos, representativos de períodos de mar relativamente mais baixo intercalados com registros de mar relativamente alto. Através da definição e análise de fácies foi possível identificar, na área do estudo, 15 (quinze) unidades faciológicas: Diamictito maciço compactado, Diamictito maciço não compactado, Diamictito maciço compactado deformado, Diamictito tabular, Diamictito lenticular, Arenito maciço tabular, Arenito maciço lenticular, Arenito com estratificação gradacional, Arenito com estratificação cruzada e granodecrescência ascendente, Arenito com estratificação cruzada de baixo ângulo e truncamentos, Siltito maciço, Siltito maciço com clastos dispersos, Folhelho ou argilito maciço, Folhelho ou argilito maciço, com clastos dispersos e Interlaminado. A análise dessas fácies, bem como seu agrupamento em associações diagnósticas (AF1, AF2, AF3 e AF4), permitiu o reconhecimento de tratos de sistemas deposicionais, TSMB, TST, TSMA e TSRGi, os quais, por sua vez, levaram à identificação de 9 (nove) seqüências de 3ª ordem, que permitiram o estabelecimento um arcabouço cronoestratigráfico para os sedimentos do Subgrupo Itararé, ao longo do perfil selecionado na área do estudo. Para se realizar a correlação pretendida entre os sedimentos do Subgrupo Itararé na área do estudo e os aflorantes na região localizada ao sul do Arco de Ponta Grossa no Paraná e Santa Catarina, foram identificados planos ou horizontes que podem ser utilizados, segundo suas características, como datum litoestratigráfico e datum bioestratigráfico. Os resultados das análises palinológicas, bem como os próprios dados físicos de superfície, demonstraram confiabilidade e viabilidade de correlação. A análise petrográfica efetuada em quatro amostras de arenitos revelou porosidades da ordem de 8 a 13%, o que permitiu caracterizar esses sedimentos como potencialmente bons para reservatórios relativamente a hidrocarbonetos ou aqüíferos. / The Itararé Subgroup (Carboniferous-Permian) of the Paraná Basin of southeastern Brazil contains the thickest, most extensive and one of the longest records of late Paleozoic glaciation in all of the Gondwana supercontinent. In the studied area, situated between the cities of Sorocaba and Itapetininga, São Paulo State, this record is characterized by glaciomarine sediments depicting intercalation of periods of high and low relative sea-level. Facies analysis of the glacigenic sediments allowed the identification of 15 lithofacie units: compact massive diamictite, massive non compact diamictite, massive non compact deformed diamictite, tabular diamictite, lenticular diamictite, massive tabular sandstone, massive lenticular sandstone, sandstone with gradational bedding, sandstone with cross bedding and normal grading, sandstone with low angle cross bedding and truncations, massive siltstone, massive siltstone with clasts, massive shale or mudstone, massive shale or mudstone with dispersed clasts and laminites. The analysis of facies and their clustering into the associations AF1, AF2, AF3 and AF4 enabled the identification of the systems tracts TSMB, TST, TSMA and TSRGi and 9 sequences of 3rd order. These provided the base to set up a local chronostratigraphic framework for the Itararé Subgroup in the studied area. In view of the possibility of correlation between the sediments of the studied area and those outcropping in the south of the Ponta Grossa arch, in the States of Paraná and Santa Catarina, some datum planes were determined. The results of the palinological analysis as well as the surface data surveyed pointed out that this correlation is feasible. Petrographic analysis of 4 samples of sandstones indicated porosities between 8 and 13 % which characterize them as potentially reservoirs for water and hydrocarbon.

O Subgrupo Itararé apresenta o registro sedimentar mais expressivo da glaciação que assolou a Bacia do Paraná durante o Neopaleozóico. Próximo à borda leste da bacia, em especial na área do estudo, entre os municípios de Sorocaba e Itapetininga, este registro é caracterizado basicamente por depósitos glaciomarinhos, representativos de períodos de mar relativamente mais baixo intercalados com registros de mar relativamente alto. Através da definição e análise de fácies foi possível identificar, na área do estudo, 15 (quinze) unidades faciológicas: Diamictito maciço compactado, Diamictito maciço não compactado, Diamictito maciço compactado deformado, Diamictito tabular, Diamictito lenticular, Arenito maciço tabular, Arenito maciço lenticular, Arenito com estratificação gradacional, Arenito com estratificação cruzada e granodecrescência ascendente, Arenito com estratificação cruzada de baixo ângulo e truncamentos, Siltito maciço, Siltito maciço com clastos dispersos, Folhelho ou argilito maciço, Folhelho ou argilito maciço, com clastos dispersos e Interlaminado. A análise dessas fácies, bem como seu agrupamento em associações diagnósticas (AF1, AF2, AF3 e AF4), permitiu o reconhecimento de tratos de sistemas deposicionais, TSMB, TST, TSMA e TSRGi, os quais, por sua vez, levaram à identificação de 9 (nove) seqüências de 3ª ordem, que permitiram o estabelecimento um arcabouço cronoestratigráfico para os sedimentos do Subgrupo Itararé, ao longo do perfil selecionado na área do estudo. Para se realizar a correlação pretendida entre os sedimentos do Subgrupo Itararé na área do estudo e os aflorantes na região localizada ao sul do Arco de Ponta Grossa no Paraná e Santa Catarina, foram identificados planos ou horizontes que podem ser utilizados, segundo suas características, como datum litoestratigráfico e datum bioestratigráfico. Os resultados das análises palinológicas, bem como os próprios dados físicos de superfície, demonstraram confiabilidade e viabilidade de correlação. A análise petrográfica efetuada em quatro amostras de arenitos revelou porosidades da ordem de 8 a 13%, o que permitiu caracterizar esses sedimentos como potencialmente bons para reservatórios relativamente a hidrocarbonetos ou aqüíferos. / The Itararé Subgroup (Carboniferous-Permian) of the Paraná Basin of southeastern Brazil contains the thickest, most extensive and one of the longest records of late Paleozoic glaciation in all of the Gondwana supercontinent. In the studied area, situated between the cities of Sorocaba and Itapetininga, São Paulo State, this record is characterized by glaciomarine sediments depicting intercalation of periods of high and low relative sea-level. Facies analysis of the glacigenic sediments allowed the identification of 15 lithofacie units: compact massive diamictite, massive non compact diamictite, massive non compact deformed diamictite, tabular diamictite, lenticular diamictite, massive tabular sandstone, massive lenticular sandstone, sandstone with gradational bedding, sandstone with cross bedding and normal grading, sandstone with low angle cross bedding and truncations, massive siltstone, massive siltstone with clasts, massive shale or mudstone, massive shale or mudstone with dispersed clasts and laminites. The analysis of facies and their clustering into the associations AF1, AF2, AF3 and AF4 enabled the identification of the systems tracts TSMB, TST, TSMA and TSRGi and 9 sequences of 3rd order. These provided the base to set up a local chronostratigraphic framework for the Itararé Subgroup in the studied area. In view of the possibility of correlation between the sediments of the studied area and those outcropping in the south of the Ponta Grossa arch, in the States of Paraná and Santa Catarina, some datum planes were determined. The results of the palinological analysis as well as the surface data surveyed pointed out that this correlation is feasible. Petrographic analysis of 4 samples of sandstones indicated porosities between 8 and 13 % which characterize them as potentially reservoirs for water and hydrocarbon.

The Desmoinesian Marmaton Group, along the southern portion of the Anadarko Basin in the Granite Wash, comprises over 2,000 feet of stacked tight sandstones and conglomerates, containing unconventional reservoirs. Uncertainty around facies variability and lateral continuity of these reservoirs represents challenges to accurate reservoir characterization due to laterally restricted submarine fan systems, and mountainront faulting. This study examines 206 wire-line well-log suites and nine ice-house flooding surfaces across an 810-square mile study area to frame fine-scale sequences, track facies changes, and estimate fault timing and duration. This high-resolution stratigraphic framework comprises a hierarchy of cycles: one third-order, three fourth-order, and eight fifth-order cycles; these were mapped across fault blocks. Mapping at the fifth-order scale documented previously un-published faults, and showed that movement occurred during two separate fifth-order cycles. Within the stratigraphic framework, well log trends, calibrated to core descriptions, enabled prediction of depositional environments in uncored wells.

No description available.