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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

High-resolution stratigraphy of Miami County, Kansas: integrated lithostratigraphy, biostratigraphy, and δ13Ccarb chemostratigraphy within the upper Pennsylvanian Missourian stage.

Oborny, Stephan C. 01 August 2015 (has links)
Recent and ongoing investigations within the Missourian Stage of eastern Kansas revealed several miscorrelations of bedrock units in the Kansas City and Lansing groups of Miami County, Kansas. These miscorrelations impact several important type and reference sections and highlight the need for additional high-resolution stratigraphic investigation of the Zarah and Linn subgroups within Miami County. This study provides high-resolution chronostratigraphy of these units through the use of detailed cm-scale lithological analyses of 33 drill cores, and conodont biostratigraphy; integrated with geophysical aeromagnetic, aerogravitational, and well-log data. This study also provides one of the first high-resolution δ13Ccarb datasets for the Upper Pennsylvanian providing a foundation for future high-resolution correlation of strata deposited during the Late Paleozoic Ice Age. Chronostratigraphic analyses revealed significant variability within nearshore shales of the upper Linn and Zarah subgroups resulting in moderate thickening and thinning of genetically related units. The thickness variability and distribution of these units is largely controlled by a bathymetric high trending 040° from southwestern Miami County. The stratigraphic resolution of this study improves upon previous investigations and supports the recent revisions to the chronostratigraphic correlations within the Kansas City and Lansing groups.
22

Biogeochemical Evolution of the Western Interior Basin of North America during a Kasimovian Highstand and Regression

Banerjee, Sikhar 2011 December 1900 (has links)
The purpose of this study is to identify and analyze the geochemical facies of the Hushpuckney Shale using XRF scanning data and the bioturbation indices, which will contribute to a better understanding of the biogeochemical environment prevalent during the deposition of the Hushpuckney Shale. The Hushpuckney Shale Member of the Swope Formation (Kasimovian Stage) preserved in KGS Spencer core 2 - 6, consists of a black shale submember overlain by bioturbated gray shale. Millimeter-scale core description and analysis of XRF scanning data enables identification of geochemical facies within the study core and contributes to understanding the environment of shale deposition. The XRF spectrometer produces X-ray image of the core and abundance values of selected major and trace elements, including iron (Fe), calcium (Ca), sulfur (S), molybdenum (Mo), zinc (Zn), vanadium (V), chromium (Cr), copper (Cu), nickel (Ni), titanium (Ti), zircon (Zr), potassium (K) and phosphorous (P). Canfield and Thamdrup's (2009) classification of geochemical environments is used to recognize oxic/aerobic, manganous-nitrogenous, ferruginous and sulfidic facies within the black shale submember. A modification of Droser and Bottjer's (1986) semi-quantitative field classification of bioturbation is used to identify facies variations within the gray shale submember. Abundance of apatite nodules and lamina in the black shale submember of the study core suggest that black shale sediments accumulated slowly in a sediment-starved basin. A high abundance of sulfide-scavenged elements, including Mo, Zn, V, Ni and Cr, identifies the sulfidic facies in the black shale submember, and indicates deposition in an oxygen-depleted environment with a high concentration of hydrogen sulfide. The overlying ferruginous facies has lower abundances of sulfide-scavenged elements and lacks cryptic Fe-laminations. The uppermost black shale submember facies, the manganous-nitrogenous facies, has cryptic Fe laminations and a relatively high P/Ca ratio. Abundance of cryptic iron laminations and apatite nodules and lamina indicates the syngenetic deposition of iron and phosphate due to Fe-P coupling mechanism. The gray shale submember is burrowed, indicating deposition under oxygenated conditions. Bioturbation indices reveal the variations in the intensity and nature of burrows within the gray shale, which corresponds to the changes in the depositional environment that may be related to the rise and fall of sea-level.
23

Depositional systems in the Pennsylvanian Canyon Group of North-Central Texas

Erxleben, A. W. 24 October 2011 (has links)
The Canyon Group (Missourian Series) is a sequence of westward-dipping, genetically related carbonate and terrigenous clastic facies that crop out in a northeast-southwest belt across North-Central Texas. The section includes stratigraphic units between the base of the Palo Pinto Limestone and the top of the Home Creek Limestone. Surface and subsurface studies within thirteen counties indicate that terrigenous clastic rocks are principally component facies of high-constructive delta systems. The Perrin delta system repeatedly prograded westward and northwestward from source areas in the Ouachita Fold Belt. Algal-crinoid banks flanked the Perrin delta system on the northeast and southwest. A typical vertical deltaic sequence includes (upward) (a) organic rich, prodelta mudstone, devoid of invertebrate fossils; (b) thin, distal delta-front sandstone and mudstone, displaying graded beds, sole marks, and flow rolls; (c) thicker proximal delta-front sandstone, exhibiting contorted beds, flow rolls, and contemporaneous faults; (d) locally contorted distributary-mouth bar sandstone; and (e) distributary channel sandstone, containing abundant trough cross stratification and local clay-chip conglomerate. Thin, coal-bearing delta-plain deposits occur locally on top of deltaic sequences. All delta facies are rich in plant debris. During delta abandonment and destruction, shallow bay-lagoon environments developed. Destructional facies include bioturbated sandy mudstone, burrowed sandstone and thin, platy argillaceous limestone with abundant invertebrate fossils. Fossiliferous mudstone units grade upward into transgressive shelf carbonate units commonly composed of phylloid algal-crinoid biomicrudite and local intraclastic biosparite shoal facies. Shelf carbonate includes onlapping sheetlike deposits; thick elongate bank deposits, which stood above the sea floor with slight bathymetric relief; massive platform carbonate; and shelf edge reef-bank accumulations. The Henrietta fan-delta system, occurring exclusively in the subsurface of Montague, Clay, Wichita, Archer and Baylor counties, is composed of thick wedges of feldspathic sandstone and conglomerate that were deposited by high-gradient fluvial systems, which built southwestward into northern Texas from source areas in the Wichita-Arbuckle Mountains of southern Oklahoma. / text
24

Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha)

Kissel, Richard 21 April 2010 (has links)
Based on dental, cranial, and postcranial anatomy, members of the Permo-Carboniferous clade Diadectidae are generally regarded as the earliest tetrapods capable of processing high-fiber plant material; presented here is a review of diadectid morphology, phylogeny, taxonomy, and paleozoogeography. Phylogenetic analyses support the monophyly of Diadectidae within Diadectomorpha, the sister-group to Amniota, with Limnoscelis as the sister-taxon to Tseajaia + Diadectidae. Analysis of diadectid interrelationships of all known taxa for which adequate specimens and information are known—the first of its kind conducted—positions Ambedus pusillus as the sister-taxon to all other forms, with Diadectes sanmiguelensis, Orobates pabsti, Desmatodon hesperis, Diadectes absitus, and (Diadectes sideropelicus + Diadectes tenuitectes + Diasparactus zenos) representing progressively more derived taxa in a series of nested clades. In light of these results, it is recommended herein that the species Diadectes sanmiguelensis be referred to the new genus Oradectes, Diadectes absitus be referred to the new genus Silvadectes, and Diasparactus be synonymized with Diadectes to produce Diadectes zenos. The phylogenetic hypothesis also reveals an evolutionary history leading to more efficient oral processing within the lineage, with successive nodes characterized by features indicative of a high-fiber diet. Within Diadectomorpha, diadectids constitute the majority of the species, suggesting that the advent of herbivory resulted in a relatively rapid radiation of species within the group, producing a clade that is markedly more species-rich than other, non-herbivorous diadectomorph taxa. An extensive review of Permo-Carboniferous tetrapod-bearing localities does, however, indicate that diadectids were not a key component of the fauna, discovered at fewer than 50 percent of the sites reviewed. These results counter suggestions that the evolution of Diadectidae led to the formation of the modern terrestrial ecosystem—where a large crop of herbivores supports a much smaller number of carnivores—during the Late Carboniferous and Early Permian.
25

Pennsylvanian coal ball flora of Indiana

Judd, Robert William January 1968 (has links)
There is no abstract available for this dissertation.
26

Palynological and paleoecological assessment of a Pennsylvanian shale overlying the Danville coal member (VII) in Sullivan County, Indiana

Madigosky, Stephen R. January 1987 (has links)
Shale samples from three Upper Pennsylvanian assemblages overlying the Danville (No. 7) Coal Member in Sullivan County, Indiana were compared with respect to miospore content. Eight samples from each of the Hawthorn, Dugger and Minnehaha mines were chemically macerated and analyzed for pollen/spore content. A total of 108 species assigned to 40 genera were recovered. A comparison of the palynoflora from the three assemblages reveals 17 genera and 32 species found in common. The palynoflora is dominated by the following four genera: Lycospora, Laevigatosporites. Punctatisporites and Punctatosporites. Genera of secondary importance include: Spinosporites, Crassispora, Calamospora, Latosporites, Cycloqranisporitesand Thymospora. These findings are similar to other palynofloras of comparable age from the United States and Europe.Abundance data at each site from the three localities were analyzed using cluster analysis. This was achieved employing the Baroni-Urboni-Buser correlation coefficient (complete linkage, furthest neighbor strategy). This method uses presence-absence data to indicate association between sites. Results revealed few taxonomic differences within or between mines. The uniformity in palynoflora observed between all sites is indicative of contemporaneous deposition which represents a regional flora. Percentage of miospore components assigned to previously established plant affinities were arranged by major plant groups. This allowed indirect comparison with megaflora from the same area as reported by Pheifer (1979). Results were found to be complementary and corroborative. Data from the three mines revealed an abundance of arborescent lycopods, ferns and sphenopsids with few gymnosperms. This is suggestive of current paleoenvironmental models which indicate a wet swamp regime.It is likely that the three areas in this study represent a small portion of a vast freshwater swamp located on the eastern periphery of the Illinois Coal Basin. This interpretation is substantiated by species composition, uniformity in palynoflora and absence of species associated with saline environments. / Department of Biology
27

Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha)

Kissel, Richard 21 April 2010 (has links)
Based on dental, cranial, and postcranial anatomy, members of the Permo-Carboniferous clade Diadectidae are generally regarded as the earliest tetrapods capable of processing high-fiber plant material; presented here is a review of diadectid morphology, phylogeny, taxonomy, and paleozoogeography. Phylogenetic analyses support the monophyly of Diadectidae within Diadectomorpha, the sister-group to Amniota, with Limnoscelis as the sister-taxon to Tseajaia + Diadectidae. Analysis of diadectid interrelationships of all known taxa for which adequate specimens and information are known—the first of its kind conducted—positions Ambedus pusillus as the sister-taxon to all other forms, with Diadectes sanmiguelensis, Orobates pabsti, Desmatodon hesperis, Diadectes absitus, and (Diadectes sideropelicus + Diadectes tenuitectes + Diasparactus zenos) representing progressively more derived taxa in a series of nested clades. In light of these results, it is recommended herein that the species Diadectes sanmiguelensis be referred to the new genus Oradectes, Diadectes absitus be referred to the new genus Silvadectes, and Diasparactus be synonymized with Diadectes to produce Diadectes zenos. The phylogenetic hypothesis also reveals an evolutionary history leading to more efficient oral processing within the lineage, with successive nodes characterized by features indicative of a high-fiber diet. Within Diadectomorpha, diadectids constitute the majority of the species, suggesting that the advent of herbivory resulted in a relatively rapid radiation of species within the group, producing a clade that is markedly more species-rich than other, non-herbivorous diadectomorph taxa. An extensive review of Permo-Carboniferous tetrapod-bearing localities does, however, indicate that diadectids were not a key component of the fauna, discovered at fewer than 50 percent of the sites reviewed. These results counter suggestions that the evolution of Diadectidae led to the formation of the modern terrestrial ecosystem—where a large crop of herbivores supports a much smaller number of carnivores—during the Late Carboniferous and Early Permian.
28

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

Cardoso, Cassiane Negreiros January 2011 (has links)
Conodontes são microfósseis potencialmente úteis para bioestratigrafia e em reconstruções paleoecológicas de rochas sedimentares paleozóicas e do Triássico. Desta forma, este estudo apresenta a classificação taxonômica e o estabelecimento das condições biocronoestratigráficas e paleoecológicas nas quais estes organismos viveram, bem como uma revisão do estágio atual do conhecimento a respeito dos conodontes e de seu aparelho alimentar. A seção analisada pertence à Formação Itaituba, Grupo Tapajós, Pensilvaniano da Bacia do Amazonas. A área de estudo localiza-se a Nordeste da cidade de Itaituba, às margens do Rio Tapajós, em um afloramento da Pedreira Calminas. A distribuição dos conodontes reconhecida define duas biozonas: uma Zona de Amplitude Diplognathodus orphanus e uma Zona de Concorrência Idiognathodus incurvus-Idiognathoides sinuatus. As espécies Diplognathodus coloradoensis, Diplognathodus orphanus e Idiognathodus incurvus formam uma associação tipicamente atokana. Baseando-se na associação descrita, a seção analisada foi definida como atokana. A espécie de melhor resolução bioestratigráfica é Diplognathodus orphanus, sendo sua distribuição restrita ao Atokano. O ambiente deposicional dominante na Bacia do Amazonas durante o Pensilvaniano é caracterizado por uma rampa carbonática rasa. Os depósitos estudados refletem uma sequência predominantemente regressiva, com a presença de gêneros de águas mais rasas, tais como Adetognathus, Diplognathodus e Ellisonia. A ocorrência de conodontes associados a braquiópodes, briozoários, crinóides e fragmentos de peixes sugere que estes estratos foram depositados em paleoambiente marinho raso, com energia de sedimentação baixa a moderada, em águas calmas, límpidas e quentes. No regime de flutuações de alta freqüência do nível do mar, os principais ambientes deposicionais eram laguna (submaré) e planície de maré (intermaré superior-supramaré inferior com tapetes microbiais). / Conodonts are useful microfossils for biostratigraphy and paleoecological reconstructions in Paleozoic and Triassic sedimentary rocks. This research aims to their taxonomic classification and to establish the biochronostratigraphic and paleoecological conditions in which these organisms lived. Furthermore, this study reviews the current knowledge about conodonts and their feeding apparatus. The section analyzed belongs to Itaituba Formation, Tapajos Group, Pennsylvanian of the Amazon Basin. The study area is located northeast of Itaituba city, on the banks of the Tapajós River, in an outcrop of Calminas Quarry. The distribution of conodonts recognized defined two biozones: Diplognathodus orphanus Amplitude Zone and Idiognathodus incurvus-Idiognathoides sinuatus Competition Zone. The species Diplognathodus coloradoensis, Diplognathodus orphanus and Idiognathodus incurvus are typically an Atokan association. Based on the association described, the section analyzed was defined as Atokan. The specie with better biostratigraphic resolution is Diplognathodus orphanus, because its distribution is restricted to the Atokan. The depositional environment prevailing in the Amazon Basin during the Pennsylvanian is characterized by a shallow carbonate ramp. The deposits studied reflect a predominantly regressive sequence, with the presence of shallow water genera, such as Adetognathus, Diplognathodus and Ellisonia. The occurrence of conodonts associated with brachiopods, bryozoans, crinoids and fish fragments suggests that these strata were deposited in a shallow marine environment, with low to moderate energy, in calm, clear and warm waters. In high frequency sea level fluctuations regime, the main depositional environments were lagoon (subtidal) and tidal flat (upper intertidal-lower supratidal with microbial mats).
29

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

Cardoso, Cassiane Negreiros January 2011 (has links)
Conodontes são microfósseis potencialmente úteis para bioestratigrafia e em reconstruções paleoecológicas de rochas sedimentares paleozóicas e do Triássico. Desta forma, este estudo apresenta a classificação taxonômica e o estabelecimento das condições biocronoestratigráficas e paleoecológicas nas quais estes organismos viveram, bem como uma revisão do estágio atual do conhecimento a respeito dos conodontes e de seu aparelho alimentar. A seção analisada pertence à Formação Itaituba, Grupo Tapajós, Pensilvaniano da Bacia do Amazonas. A área de estudo localiza-se a Nordeste da cidade de Itaituba, às margens do Rio Tapajós, em um afloramento da Pedreira Calminas. A distribuição dos conodontes reconhecida define duas biozonas: uma Zona de Amplitude Diplognathodus orphanus e uma Zona de Concorrência Idiognathodus incurvus-Idiognathoides sinuatus. As espécies Diplognathodus coloradoensis, Diplognathodus orphanus e Idiognathodus incurvus formam uma associação tipicamente atokana. Baseando-se na associação descrita, a seção analisada foi definida como atokana. A espécie de melhor resolução bioestratigráfica é Diplognathodus orphanus, sendo sua distribuição restrita ao Atokano. O ambiente deposicional dominante na Bacia do Amazonas durante o Pensilvaniano é caracterizado por uma rampa carbonática rasa. Os depósitos estudados refletem uma sequência predominantemente regressiva, com a presença de gêneros de águas mais rasas, tais como Adetognathus, Diplognathodus e Ellisonia. A ocorrência de conodontes associados a braquiópodes, briozoários, crinóides e fragmentos de peixes sugere que estes estratos foram depositados em paleoambiente marinho raso, com energia de sedimentação baixa a moderada, em águas calmas, límpidas e quentes. No regime de flutuações de alta freqüência do nível do mar, os principais ambientes deposicionais eram laguna (submaré) e planície de maré (intermaré superior-supramaré inferior com tapetes microbiais). / Conodonts are useful microfossils for biostratigraphy and paleoecological reconstructions in Paleozoic and Triassic sedimentary rocks. This research aims to their taxonomic classification and to establish the biochronostratigraphic and paleoecological conditions in which these organisms lived. Furthermore, this study reviews the current knowledge about conodonts and their feeding apparatus. The section analyzed belongs to Itaituba Formation, Tapajos Group, Pennsylvanian of the Amazon Basin. The study area is located northeast of Itaituba city, on the banks of the Tapajós River, in an outcrop of Calminas Quarry. The distribution of conodonts recognized defined two biozones: Diplognathodus orphanus Amplitude Zone and Idiognathodus incurvus-Idiognathoides sinuatus Competition Zone. The species Diplognathodus coloradoensis, Diplognathodus orphanus and Idiognathodus incurvus are typically an Atokan association. Based on the association described, the section analyzed was defined as Atokan. The specie with better biostratigraphic resolution is Diplognathodus orphanus, because its distribution is restricted to the Atokan. The depositional environment prevailing in the Amazon Basin during the Pennsylvanian is characterized by a shallow carbonate ramp. The deposits studied reflect a predominantly regressive sequence, with the presence of shallow water genera, such as Adetognathus, Diplognathodus and Ellisonia. The occurrence of conodonts associated with brachiopods, bryozoans, crinoids and fish fragments suggests that these strata were deposited in a shallow marine environment, with low to moderate energy, in calm, clear and warm waters. In high frequency sea level fluctuations regime, the main depositional environments were lagoon (subtidal) and tidal flat (upper intertidal-lower supratidal with microbial mats).
30

Conodont-based correlation of major cyclothems in lower Cherokee group (Lower Desmoinesian, Middle Pennsylvanian), Oklahoma to Iowa

Marshall, Thomas Robert 01 May 2010 (has links)
Three named major cycles of marine transgression and regression (cyclothems) in the lower Cherokee Group are recognized from the Arkoma Basin margin in east-central Oklahoma across the northern Midcontinent shelf, on the basis of distinctive conodont morphotypes. The lowest of these (McCurtain) is characterized by Idiognathodus cf. praeobliquus and absence of I. obliquus and Idiognathoides. The middle cyclothem (Doneley) is the first major cyclothem to yield I. obliquus. The uppermost (Inola) yielded abundant Idiognathodus, Neognathodus and Idioprioniodus, and sparse Gondolella, and is characterized by large numbers of Idiognathodus podolskensis. All three contain large numbers of I. amplificus. At the base of the succession, the genus Idiognathoides in three cores from northeastern Kansas to south-central Iowa confirms the presence of Atokan strata in the Forest City Basin. The McCurtain cyclothem extends from Oklahoma to the Forest City Basin in northeastern Kansas. The Doneley and Inola cyclothems extend from Oklahoma into Iowa. The Inola Limestone of Oklahoma is equivalent to the Hackberry Branch Limestone of western Missouri. The Bluejacket Coal of Oklahoma, at the base of the Inola cyclothem, is likely equivalent to Bluejacket A Coal of Kansas, Weir B or C coals in Missouri, and a middle Laddsdale coal in Iowa. The Rowe Coal of Oklahoma, Kansas, and Missouri, at the base of the Doneley cyclothem, is likely equivalent to the Cliffland Coal of Iowa. Inconsistent marine lithofacies in all three cyclothems suggest a complex depositional history on irregular surfaces.

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