Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 149-153). Also available in electronic version.

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M. S. in geology)--Washington State University, May 2006. / Includes bibliographical references (p. 26-28).

Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 95, 55 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.

Thesis (M. Phil.)--University of Hong Kong, 2006. / Also available online.

The thesis examines the theoretical bases for determining optimal pollution levels in the Trent River Basin, demonstrates that neither the organization of a so-called "market in pollution rights" nor the construction of marginal effluent treatment cost and marginal damage functions is a practical means of finding those levels, and proposes ways for using existing data and the Trent Research Programme river model to determine "roughly optimal" pollution levels.

This research aims to better understand drainage systems during mid to late Large Igneous Province (LIP) formation. A multidisciplinary study was conducted on the Lewiston Basin in the Columbia River Flood Basalt Province and the Skye Lava Field in the North Atlantic Igneous Province. A general model for drainage systems in LIPs was developed with three stages. In the early-LIP stage, the volcanic and drainage systems are confined to small basins, but as the volumetric eruption rate increases the regional drainage system is forced to the edge of the lava field. During the mid-LIP stage, the eruption rate decreases and the drainage system moves into the lava field, depositing channel sediments in the lowest parts of province while finer sediments or palaeosols develop in topographically higher areas. In the Skye Lava Field the drainage system was dominated by the uplift of the Rum Central Igneous Complex and included the incision of shallow valleys, whereas in the Lewiston Basin the most important effect was the structural control on basin topography. During the lateLIP stage, topographically high areas experience significant incision into the lava field which are filled by intracanyon flows (thick canyon-filling lava flows). These intracanyon flows may compartmentalise potential reservoirs deposited between earlier lava flows. Siliciclastic sand bodies were observed up to 12 m thick and 850 m across with minor exposure gaps, and were correlated across up to 15 km. The palynofloras associated with a number of palaeoenvironments in each province were identified the effects of other controls on the palaeoecology such as moisture availability, ashfall and substrate were established. The changes in the paJaeoclimate of the Lewiston Basin were studied using palaeosol geochemistry and palynology.

This research aims to develop a large-scale locally relevant flood risk screening tool, that is, one capable of generating accurate probabilistic inundation maps quickly while still detecting localized nuisance-destructive flood potential. The CASCADE 2001 routing model is integrated with GIS to compare the predicted flood response to heavy rains at the watershed, subwatershed, and municipal levels. Therefore, the objective is to evaluate the impact of scale for determining flood risk in a community. The findings indicate that a watershed-level analysis captures most flooding. However, the flood prediction improves to match existing FEMA flood maps as drill-down occurs at the subwatershed and municipal scales. The drill-down modeling solution presented in this study provides the necessary degree of local relevance for excellent detection in developed areas because of the downscaling techniques and local infrastructure. This validated model framework supports the development and prioritization of protection plans that address flood resilience in the context of watershed master planning and the Community Rating System. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection

Studies are currently underway to determine the suitability of Yucca Mountain in Nevada as the nation's first high-level nuclear waste repository. Values of net infiltration are required to determine pre-waste emplacement groundwater travel times and the performance of the repository as a waste containment system. The objective of this study was to develop a numerical model to perform water balance calculations and predict rates of net infiltration for the site. The model included processes of precipitation, runoff, evapotranspiration, infiltration, and redistribution of water within a soil profile. The watershed was divided into 477 grid cells 75.7 x 75.7 m. The elevation, slope, aspect, and hydrologic properties were assumed to be constant within a grid cell but varied from one cell to the next Water balance calculations were performed for each cell using a one-dimensional form of Richards equation. The solution was obtained using the finite difference method with Newton-Raphson iteration. The model was calibrated using water content data obtained from neutron-moisture meter measurements in boreholes located in Pagany Wash Watershed Measurements were made in channel and terrace alluvium and in tuffs. Computer simulations reproduced water content data for a major precipitation event that occurred in 1984. Simulations verified the importance of antecedent soil water content in controlling the occurrence of runoff. Sensitivity analysis indicated that the soil and alluvium grain-size distributions, which are used to calculate unsaturated hydraulic conductivity, can greatly affect predicted rates of water movement / Graduation date: 1991

In many parts of the world, developed as well as developing, rivers are not gauged for continuous monitoring. Streamflow prediction at such "ungauged" river catchments requires information transfer from gauged catchments that are perceived to be hydrologically similar to them. Achieving good predictability at ungauged catchments requires an in-depth understanding of the physical and climatic controls on hydrologic similarity among catchments. This dissertation attempts to gain a better understanding of these controls through three independent research studies that use data from catchments across the continental United States. In the first study, I explore whether streamflow similarity among nearby catchments is preserved across flow conditions. Catchments located across four river basins in the northeast United States are analyzed to quantify the spatio-temporal variability in streamflows across flow percentiles. Results show that similarity in catchment stream response is dynamic and highly dependent on flow conditions. Specifically, the coefficient of variation is high at low flow percentiles and gradually reduces for higher flow percentiles. This study concludes that high variability at low flows is controlled by the dominance of high evaporative demand, whereas low variability at high flows is controlled by the dominance of precipitation input relative to evapotranspiration. In the second study, I examine whether streamflow similarity among catchments exists across a wide range of climatic and geographic regions. Data from 756 catchments across the United States is used and daily streamflow at each catchment is simulated using distance-based streamflow interpolation from neighboring catchments. With this approach, high predictability at a catchment indicates that catchments in its vicinity have similar streamflows. Results show that high predictability catchments are mainly confined to the Appalachian Mountains, the Rocky Mountains, and Cascade Mountains in the Pacific Northwest. Low predictability catchments are located mostly in the drier regions of US to the west of Mississippi river. Results suggest that streamflow similarity among nearby catchments is more likely in humid runoff-dominated regions than in dry evapotranspiration-dominated regions. In the third study, my goal is to identify what constitutes the essential information that must be transferred from gauged to ungauged catchments in order to achieve good model predictability. A simple daily time-step rainfall-runoff model is developed and implemented over 756 catchments located across the United States. Results show that the rainfall-runoff model simulates well at catchments in humid low-energy environments, most of which are located in the eastern part of the US, the Rocky Mountains, and to the west of Cascade Mountains. Within these regions, transfer of the parameter characterizing hydrograph recession provides reliable streamflow predictions at ungauged catchments, with a loss in prediction efficiency of less than 10% in most catchments. The results presented in this dissertation show that climate exerts a strong control on hydrologic similarity among catchments. The results further suggest that an understanding of the interaction between climate and topography is essential for quantifying the spatial variability in catchment hydrologic behavior at a regional scale.