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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.
31

The Origin of Asymmetry of Position of Longitudinal Subsequent Streams in the Folded Appalachians

Broscoe, Andy Joe January 1951 (has links)
No description available.
32

An evaluation of polishing pond effectiveness

Mueldener, Karl W January 2011 (has links)
Digitized by Kansas Correctional Industries
33

Controls on silesian sedimentation in the Pennine Basin, UK, and Appalachian Basin, eastern Kentucky

O'Beirne, Andrew Moray January 1996 (has links)
No description available.
34

Basin analog approach answers characterization challenges of unconventional gas potential in frontier basins

Singh, Kalwant 25 April 2007 (has links)
To continue increasing the energy supply to meet global demand in the coming decades, the energy industry needs creative thinking that leads to the development of new energy sources. Unconventional gas resources, especially those in frontier basins, will play an important role in fulfilling future world energy needs. We must identify and quantify potential unconventional gas resources in basins around the world to plan for their development. Basin analog assessment is one technique that can be used to identify and quantify unconventional gas resources that is less expensive and less time consuming. We have developed a basin analog methodology that is useful for rapidly and consistently evaluating the unconventional hydrocarbon resource potential in exploratory basins. We developed software, Basin Analog System (BAS), to perform and accelerate the process of identifying analog basins. Also, we built a database that includes geologic and petroleum systems information of intensely studied North America basins that contain well characterized conventional and unconventional hydrocarbon resources. We have selected 25 basins in North America that have a history of producing unconventional gas resources. These are “reference” basins that are used to predict resources in frontier or exploratory basins. The software assists us in ranking reference basins that are most analogous to the target basin for the primary purpose of evaluating the potential unconventional resources in the target basin. The methodology allows us to numerically rank all the reference basins relative to the target basin. The accuracy of the results depends on the descriptions of geologic and petroleum systems. We validated the software to make sure it is functioning correctly and to test the validity of the process and the database. Finding a reference basin that is analogous to a frontier basin can provide insights into potential unconventional gas resources of the frontier basin. Our method will help industry predict the unconventional hydrocarbon resource potential of frontier basins, guide exploration strategy, infer reservoir characteristics, and make preliminary decisions concerning the best engineering practices as wells are drilled, completed, stimulated and produced.
35

Miocene stratigraphy and depositional framework of northeastern Maracaibo Basin, Venezuela : implications for reservoir heterogeneity prediction in tectonically-active settings /

Guzmán Espinal, José Ignacio, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 177-191). Available also in a digital version from Dissertation Abstracts.
36

Escarpement de faille synsédimentaire : perturbation des écoulements gravitaires sous-marins et détermination de la cinématique des failles /

Pochat, Stéphane. January 2003 (has links)
Thesis (doctoral)--Université de Rennes I, 2003. / Errata sheets inserted. Includes bibliographical references (p. 239-253, 266-270). Also available on the Internet.
37

Late quaternary palaeolacustrine environments of the Middle Kalahari

Burrough, Sallie L. January 2008 (has links)
No description available.
38

Structural study of the southwest part of Elk Basin Anticline, Bighorn Basin, Wyoming

Huson, Sarah Ann January 2002 (has links)
A subsurface and surface structural study was completed in the southwest part of the Elk Basin Anticline, Wyoming. The goals of this study were to better improve preexisting geologic surface maps of the area and to better understand subsurface structural relationships. A normal fault with a splay to the north was recorded through sections 25, 26. and 35 of T58N, RI00W. Using well logs to create across section, this fault was traced in the subsurface. Strike and dip measurements in undisturbed areas of the anticline averaged 332° (azimuth) or N28W (quadrant). In an area of anomalous strike (section 26 of T58N, R1 00W), strike readings averaged 303° (azimuth) or N57W (quadrant). This region has been interpreted as an area rotated counter clockwise due to drag on a subsurface tear fault located at the northern end of the anticline. The current study is significant since it lends support to a little studied Laramide structural feature. / Department of Geology
39

Hydrothermal activity along the northern Mid-Atlantic Ridge and in the Bransfield Strait backarc basin, Antarctica

Chin, Carol Sue 10 August 1998 (has links)
Graduation date: 1999
40

Prediction of ungauged basins - uncertain criteria conditioning, regionalization and multimodel methods

Wyatt, Adam January 2009 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / The purpose of rainfall-runoff modelling, like all environmental modelling is to generate simulations that accurately mimic those encountered in the system being modelled. Once this is achieved, the model may then be used to study the catchment response under conditions that have not previously been observed, such as the determination of extreme flood levels. The complex behaviour of the processes involved in the generation of streamflow mean that to achieve a usable model, simplifications must be made. This inevitably leads to the introduction of model error into the simulations, as these simplifications cannot reproduce the level of response variation encountered in a natural system. As a consequence, a model that performs well at some times may be inappropriate at other times. The MultiModel approach is an alternative method of rainfall-runoff modelling that uses numerous alternative process descriptions to generate a suite of unique rainfall runoff models. These models are calibrated and applied to allow for simulation responses that incorporate not only parameter variability but model structure variability. It is shown that the application of the MultiModel method to four test catchments produced simulated confidence limits that are much more likely to contain flood peaks that are beyond the range encountered during the calibration process than using a single model. This is due to the wider confidence limits generated as a result of the greater structure variability available to the MultiModel. The wider confidence limits are therefore a better reflection of our true understanding of the system being modelled. The prediction of ungauged basins presents an additional challenge to rainfallrunoff modelling. Most methods involve some form of regionalization of model parameters. These approaches are very limited in that they are restricted by model selection and application range. Two unique methods for the prediction of ungauged basins are presented that overcome these restrictions. The first attempts to condition a rainfall-runoff model using uncertain criteria, normally used as a supplement to more common calibration procedures. These criteria include estimates of flood peaks, baseflow, recession and saturated area. It is shown that combinations of these criteria provide a powerful means of constraining the parameter space and reducing the simulation uncertainty. The second approach to model conditioning for ungauged basins uses an alternative method of regionalization that focuses on the estimation of flow characteristics rather than model parameter values. Strong relationships between flow characteristics (such as runoff coefficients, flow duration curves and coefficient of variation) and catchment conditions (such as area, mean annual rainfall and evaporation) are identified for catchments across Australia. Using the estimated ranges of these flow characteristics as assessment criteria, a rainfall-runoff model is successfully conditioned to adequately reproduce the streamflow response of the four test catchments. In particular it is shown that the use of numerous characteristics in tandem further improves the conditioning for the test catchments.

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