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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.
11

Geology and hydrology of the Roswell Artesian basin, New Mexico.

Maddox, George Edward, January 1969 (has links) (PDF)
Thesis (Ph. D. - Mining and Geological Engineering)--University of Arizona, 1969. / Part of folded illustrative matter in pocket. Includes bibliographical references (leaves 139-141).
12

Application of the gravity method to ground-water volume determinations of alluvial basins

Greenes, Kent A. January 1980 (has links) (PDF)
Thesis (M.S. - Geosciences)--University of Arizona. / Includes bibliographical references (leaves [26-28]).
13

A methodology for the design of wet detention basins for treatment of highway stormwater runoff /

Dorman, Michael E., January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 74-76). Also available via the Internet.
14

Further hydrogeologic investigations in the Davis Spring drainage basin, Greenbrier County, West Virginia

Tudek, John Kazimierz. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains ix, 157, [1] p. : ill. (some col.), col. maps. Vita. Includes abstract. Includes bibliographical references (p. 116-120).
15

Hydraulic and removal efficiencies in sedimentation basins

Wallace, Alfred T., January 1965 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1965. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
16

Subsurface mapping of Ellesmerian onlaps testing the opening of the Arctic Canada Basin /

Connelly, Brian A. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 111 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 72-75).
17

Sedimentology and sequence stratigraphy of the Congo and Kalahari basins of South Central Africa and their evolution during the formation and break-up of West Gondwana

Linol, Bastien January 2013 (has links)
The high elevated (ca. 1100 m) continental Kalahari Basin (KB) of southern Africa and the linked lower lying (ca. 400 m) Congo Basin (CB) of central Africa preserve in their interiors extensive sedimentary rock sequences and sediments that represent a unique record of the Phanerozoic geodynamic and climatic evolution of sub-Saharan Africa. In this thesis, field observations and new borehole data from the Democratic Republic of Congo (DRC) and Botswana are integrated with new paleontology and geochronology to present a substantially revised stratigraphy for the CB, and south-central Africa in general. This work also introduces a new multiphase model for the subsidence and uplift history of the CB, and improves correlations with the Cape-Karoo Basin (CKB) of South Africa and the Paraná Basin (PB) of south-east Brazil. Four deep boreholes, each between 2 and 4.5 km deep, drilled in the centre of the CB in the 1950’s and 1970’s are re-examined together with the colonial literature (in French) and available seismic data. This stratigraphic and basin analysis is complemented with new U-Pb dates of detrital zircons from core-samples of two of the boreholes (Samba and Dekese), as well as from samples collected during field work in the Kwango region of the south-west DRC. This work, for the first time, constrains the maximum ages and source provenances of the successions in the CB. Following the Pan African orogens (ca. 650-530 Ma), extensive sequences of red beds were deposited by regional paleocurrents to the south. These are now best preserved (1 km thick) along the West Congo, Oubanguides, and Lufilian Belts surrounding the CB. Overlying a hiatus that represents most of the early-Paleozoic, is a 1 to 3 km thick succession of easterly derived glacial, and then continental sequences of the Karoo Supergroup. This succession records the first main episode of subsidence [10-15 m/Ma], interrupted by a phase of uplift that is likely related to far-field intracontinental deformation within Gondwana supercontinent during the Variscan and Cape Fold orogenies (ca. 250-330 Ma) at its peripheries. Detrital zircons from the lower Karoo diamictites are dated at 1.85-2.05 Ga and 1.37- 1.42 Ga, and thus sourced from Paleoproterozoic (Eburnean) and mid-Mesoproterozoic (Kibaran type-I) basement rocks in Uganda and Tanzania. Zircons from all the other successions in the CB date predominantly at 950-1050 Ma and 500-800 Ma. These are derived from sediment recycling of late-Mesoproterozoic (Kibaran type-II) and late- Neoproterozoic (Pan African) sources in the Central African Republic (CAR) and Chad. A distinct unconformity across the Karoo Supergroup in the CB is overlain by 500- 1000 m Jurassic-Cretaceous sequences, here named the Congo Supergroup. During initial rapid subsidence [10-50 m/Ma], late-Jurassic (Kimmeridgian) shallow marine to continental sedimentation attests to a short transgression of proto-Indian Ocean waters into the northern CB (at 160 m above present day sea-level), succeeded by widespread deposition of aeolian dunes that extend from the southern CB to the PB in South America. The youngest zircons from these aeolian sediments in the CB date at 190 Ma and 240-290 Ma, and most likely indicate the influence of extensive silicic volcanic ash derived from the proto-Andes along the south-western margin of Gondwana. Two superimposed mid-Cretaceous (Albian-Cenomanian) lacustrine sequences in the central CB record a succeeding, slower [10-15 m/Ma], phase of basin subsidence during the opening of the South Atlantic (ca. 85-135 Ma). These Cretaceous sequences are in turn truncated by another regional peneplanation surface covered by Cenozoic (Eocene) silcretized sands and alluviums of the Kalahari Group, only 50-250 m thick in the centre of the CB. Southward, on top of the Kalahari Plateau in the central desert region of north-west Botswana, new boreholes intercepted laterally equivalent condensed lacustrine carbonates and calcretes (20-50 m thick) covered by sands. These terrestrial sequences are key archives of late-Mesozoic – Cenozoic paleo-climate changes, yet they remain stratigraphically unresolved. This new analysis of the Phanerozoic continental basins of south-central Africa and their equivalents in South America, opens a fresh continental-scale window into how West Gondwana break-up and concomitant epeirogenic uplifts of Kalahari (>2 km) and Congo (>200 m) are linked to interactions between the lithosphere and mantle geodynamics, and how these processes likely affected global climate changes.
18

Streamflow Estimation in Ungauged Basins Using Regionalization Methods

Razavi, Tara 11 1900 (has links)
Considering the growing population of the earth and the decreasing water resources, the need for reliable and accurate estimation and prediction of streamflow time series is increasing. Due to the climate change and anthropogenic impacts on hydrologic systems, the estimation and prediction of streamflow time series remains a challenge and it is even more difficult for regions where watersheds are ungauged in terms of streamflow. The research presented in this dissertation, was scoped to develop a reliable and accurate methodology for daily streamflow prediction/estimation in ungauged watersheds. The study area in this research encompasses Ontario natural watersheds with various areas spread in different regions. In this research work nonlinear data-driven methods such as Artificial Neural Networks (ANN) and conventional methods such as Inverse Distance Weighted (IDW) as well as their combination are investigated for different steps in streamflow regionalization. As such, Watershed classification prior to regionalization is investigated as an independent step in regionalization. Nonlinear classification techniques such as Nonlinear Principal Component Analysis (NLPCA) and Self-Organizing Maps (SOMs) are investigated for watershed classification and finally a methodology which combines watershed classification, streamflow regionalization and hydrologic model optimization is presented for reliable streamflow prediction in ungauged basins. The results of this research demonstrated that a multi-model approach which combines the results of proposed individual models based on their performance for the gauged similar and close watersheds to the ungauged ones can be a reliable streamflow regionalization model for all watersheds in Ontario. Physical similarity and spatial proximity of watersheds was found to play an important role in similarity between the streamflow time series, hence, it was incorporated in all individual models. It was also shown that watershed classification can significantly improve the results of streamflow regionalization. Investigated nonlinear watershed classification techniques applicable to ungauged watersheds can capture the nonlinearity in watersheds physical and hydrological attributes and classify watersheds homogeneously. It was also found that the combination of watershed classification techniques, regionalization techniques and hydrologic models can impact the results of streamflow regionalization substantially. Furthermore, to evaluate the uncertainty associated with the predictions in ungauged watersheds, an ensemble modelling framework is proposed to generate ensemble predictions based on the proposed regionalization model. / Dissertation / Doctor of Philosophy (PhD)
19

Earthquake site effect modeling in sedimentary basins using a 3-D indirect boundary element-fast multipole method

Lee, Jimin. January 2007 (has links)
Thesis (Ph. D.)--State University of New York at Binghamton, Department of Geological Sciences and Environmental Studies, 2007. / Includes bibliographical references (leaves 308-314).
20

The formation of authigenic xenotime in Proterozoic sedimentary basins : petrography, age and geochemistry /

Vallini, Daniela Alessandra. January 2006 (has links)
Thesis (Ph.D.)--University of Western Australia, 2006.

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