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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.
91

Subsurface analysis of Sundaland basins : source rocks, structural trends and the distribution of oil fields

Pethe, Swardhuni 14 December 2013 (has links)
According to the Ade observation (Ade, W., pers. Comm.) “95% of all commercial oil fields in the Sumatra region occur within 17 km of seismically mappable structural grabens in the producing basins”. The Ade observation proposes a link between the subsidence of the source rocks (the Talang Akar Formation) in the grabens and the maturity of the organic material. To test the validity of the Ade observation, subsurface mapping of the region was carried out using geophysical logs. Using the well log information, the basement and the formation tops have been mapped with a special emphasis on Talang Akar and Air Benakat Formations. The isopach maps of these formations show that most of the producing wells on the Sunda shelf are in fact located in and around the major structural basins. Trends in the occurrence of the oil fields have also been observed which are analogous to the orientation of the grabens. Structural mapping of the basins have identified several wrench faults. These are of particular interest as wrench faults provide good structural traps for oil in the Los Angeles and the North Sumatra Basins and may prove to be very important for future exploration in southern Sumatra and northwest Java. In South Sumatra Basin, 77.78% of the potential oil fields are located in the 17 km margin from the grabens. For Sunda/Asri Basins and the Ardjuna Basin, it is 100 and 92 respectively. Identifying the source rocks in this 17 km window will enhance the success rate of oil exploration in the Sundaland Basins. / Department of Geological Sciences
92

An analysis of fracture systems, lithologic character and kinematic history of Paleozoic rock formations in a portion of southeastern Indiana

Keene, David G. January 1989 (has links)
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
93

Quartz arenites of the uppermost Cambrian-lowermost Ordovician Kamouraska Formation, Québec, Canada : gravity flow deposits of eolian sand in the deep sea

Malhame, Pierre. January 2007 (has links)
The uppermost Cambrian-Lower Ordovician Kamouraska Formation in the external Humber Zone of the Quebec Appalachians consists of dominant thick massive to graded quartz arenite beds, subordinate pebble conglomerate and intercalated thin shale and siltstone beds. It was deposited by hyperconcentrated to concentrated density flows in a meandering submarine canyon on the continental slope bordering the Iapetus Ocean. Turbidity currents deposited beds with turbidite structure divisions. The sandstones consist of well sorted, well rounded quartz sand with frosted grains. Scanning electron microscopy reveals the presence of textures supporting eolian transport before redeposition in the deep sea. The Kamouraska quartz arenites are considered an ancient equivalent of Pleistocene eolian-sand turbidites on an abyssal plain off West Africa consisting of Sahara sand. Sand provenance is attributed to eolian equivalents of the Cairnside Formation of the Potsdam Group. The quartz arenites of the Kamouraska Formation provide a variant to tectonic sandstone provenance proposed in the scheme of Dickinson and Suczek (1979).
94

Middle cretaceous dinosaur tracks at Cerro de Cristo Rey, Sunland Park, New Mexico and a comparison with other paleocoastal tracksites of the Southwestern US

Kappus, Eric J., January 2007 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
95

Depositional environments and sequence stratigraphy of the Rockwell-Price Formation in western Maryland, south-central Pennsylvania, and northern West Virginia

Dolezal, Darin A. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiv, 225 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 113-116).
96

Geology of the middle and upper Eocene McIntosh Formation and adjacent volcanic and sedimentary rock units, Willapa Hills, Pacific County, southwest Washington /

Moothart, Steve Rene' January 1992 (has links)
Thesis (M.S.)--Oregon State University, 1993. / Includes mounted photographs. Three folded plates in pocket. Typescript (photocopy). Includes bibliographical references (leaves 213-225). Also available on the World Wide Web.
97

Elevation, longitudinal profile, and schmidt hammer analysis Of strath terraces through Capitol Reef National Park, Utah : bedrock channel response to climate forcing? /

Eddleman, James L., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2005. / Includes bibliographical references.
98

Καταλληλότητα αδρανών υλικών για έρμα σιδηροδρομικών γραμμών: έρευνα σε δείγμα Νο2 βασικών και υπερβασικών πετρωμάτων

Κυριαζοπούλου, Ελένη 07 October 2011 (has links)
Στη διπλωματική αυτή εργασία γίνεται μελέτη της τεχνικογεωλογικής συμπεριφοράς βραχωδών σχηματισμών για την καταλληλότητά τους και την χρήση τους ως αδρανή υλικά σε έρμα σιδηροδρομικών γραμμών ταχείας κυκλοφορίας. / -
99

Καταλληλότητα αδρανών υλικών για έρμα σιδηροδρομικών γραμμών: έρευνα σε δείγμα Νο1 βασικών και υπερβασικών πετρωμάτων

Πανούτσου, Νικολίτσα 07 October 2011 (has links)
Στην πτυχιακή αυτή εργασία μελετάται η συμεριφορά των βραχωδών σχηματισμών που μπορούν να χρησιμοποιηθούν ως αδρανή υλικά για έρμα σιδηροδρομικών γραμμών ταχείας κυκλοφορίας. / -
100

Fluidos inibidos para perfuração de folhelhos.

LUCENA, Danielly Vieira de. 24 January 2018 (has links)
Submitted by Gustavo Nascimento (gustavo.diniz@ufcg.edu.br) on 2018-01-24T12:44:30Z No. of bitstreams: 1 DANIELLY VIEIRA DE LUCENA – TESE PPGCEMAT 2018.pdf: 3908947 bytes, checksum: fcd5d2bc8ce65b22562ab8feb11da6ef (MD5) / Made available in DSpace on 2018-01-24T12:44:30Z (GMT). No. of bitstreams: 1 DANIELLY VIEIRA DE LUCENA – TESE PPGCEMAT 2018.pdf: 3908947 bytes, checksum: fcd5d2bc8ce65b22562ab8feb11da6ef (MD5) Previous issue date: 2014-07-21 / Estudar formações geológicas suscetíveis à hidratação se configura como um desafio por se tratar de um fenômeno responsável por cerca de 90% dos problemas relacionados com a perfuração de poços de petróleo, além de se tratar de um tema que pouco se conhece sobre os mecanismos que regem tal fenômeno e ainda, pela escassez de estudos voltados para a análise de diferentes produtos que evitem a ocorrência da problemática (inibidores) da hidratação. Deste modo, este trabalho objetivou o estudo e a avaliação da eficiência de fluidos de perfuração aquosos inibidos e isentos de cloro no controle da hidratação de formações de folhelhos de várias regiões do país. Para isto, foram estudadas treze amostras de folhelhos brasileiros e duas amostras de argilas bentoníticas. Inicialmente, realizou-se a caracterização de todas as amostras com a finalidade de identificar as mais suscetíveis à hidratação. Em seguida, foi realizado o estudo para selecionar a melhor concentração de inibidor para contenção da expansão de argilas reativas e a partir dos resultados foi estabelecida a concentração ótima de inibidor (20g/ 350mL de água). A partir disto, foram desenvolvidos fluidos de perfuração com quatro diferentes inibidores de argila expansiva (sulfato de potássio, acetato de potássio, citrato de potássio e cloreto de potássio) e determinados o pH, a densidade, as propriedades reológicas e de filtração. Foi também determinada a dispersibilidade dos fluidos desenvolvidos. A partir dos resultados, concluiu-se que foram desenvolvidos com êxito fluidos de perfuração que apresentam satisfatórios desempenhos reológicos e de filtração e propriedades inibitivas. Excelentes resultados em relação às taxas de dispersibilidade também foram obtidas. De modo geral, os resultados obtidos indicam que o inibidor citrato de potássio apresentou o melhor controle da reatividade de formações reativas e que o mesmo se constitui em um produto alternativo à substituição dos inibidores comerciais utilizados pela indústria. / To study geological formations susceptible to hydration is a challenge because it is a phenomenon responsible for about 90% of problems associated to the drilling of oil well, in addition it is a topic that deal with mechanisms little known governing this event and also due to the scarcity of the studies focused on the analysis of different products that avoid the occurrence of the hydration problems (inhibitors). In this way, the aim of this work was study the efficiency of the based water inhibited drilling fluids free of chlorine in the control of hydration of shale formation from various regions of the country. For this, it was studied thirteen samples of brazilian shales and two samples of bentonite clays. Firstly, it was done the characterization of the samples with the purpose of identifying the more susceptible to hydration. Then, it was studied the best concentration of the inhibitor to hinder the expansion of reactive clays and from these results it was established the best concentration of inhibitor (20g/350mL of water). After, it was developed drilling fluids with four different inhibitors of expansive clay (potassium phosphate, potassium acetate, potassium citrate and potassium chloride) and estimated the pH, density, rheological and filtration properties of these fluids. It is also estimated the dispersibility of the developed fluids. From the results, it was concluded that the fluids was developed with success and presented satisfactory rheological, filtration and inhibits properties. Excellent results with regard to the rates of dispersibility were also obtained. In general, the results indicated that the inhibitor potassium citrate presented the best control of reactivity of the formation and it constitutes an alternative to substitute the commercial inhibitors used by petroleum industry.

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