Thesis (Ph. D.)--Boise State University, 2006. / Includes abstract. Includes bibliographical references (leaves 122-127). Also available online via the ProQuest Digital Dissertations database.

Typescript, etc. / Digitized by Kansas State University Libraries

The inverse problem of groundwater hydrology is difficult to solve and yet critical for the reliability of model predictions. In this dissertation, the problem is posed within the framework of maximum likelihood estimation by means of an estimation criterion which includes head measurements as well as prior information of the model parameters. Parameters that can be estimated include the principal values and directions of transmissivity (or hydraulic conductivity), storativity (or specific storage), recharge rates, boundary heads or fluxes, leakances, and parameters controlling the error structure of the data. In transient problems, the initial steady-state of the system can also be derived and/or taken advantage of. To minimize the estimation criterion, its gradient is evaluated by a finite element adjoint state method which leads to considerable savings in computer time and storage. The minimization -, performed -by a -combination- of gradient methads, is sbawn, bath theoretically and with examples, to result in stable solutions for a wide range of realistic situations. Synthetic and field examples are included to demonstrate various features of the approach. Applications of the methodology to problems of model selection, network design, and quantification of the worth of data are highlighted.

No description available.

No description available.

No description available.

"The St. Marks River basin encompasses a large portion of Leon, Jefferson and Wakulla counties in northwest Florida, extending from near the Georgia-Florida border to the Gulf of Mexico. Geology and surface topography of the basin is controlled by sediments of Upper Eocene, Oligocene, Miocene, and Quaternary age. In the portion of the basin south of the Cody Scarp, the Middle and Upper Miocene sediments have been eroded and the surface elevations are much lower than the northern upland. The Florida Aquifer is the principal source of ground water for the St. Marks basin. The major producing zone of the aquifer is comprised of limestones of Upper Eocene to Lower Miocene age. Overlying younger sediments serve as confining units throughout the northern half of the basin. Hydrologically, the aquifer is more transmissive near the St. Marks River. Water levels are generally higher in the recharge area in the northern portion of the basin with flow paths generally towards the springs and discharge areas near the Gulf of Mexico. Recharge is predominantly from local rainfall although some ground water is being contributed from the adjacent basin to the north"--Abstract. / Typescript. / "December 1984." / "Submitted to the Department of Geology in partial fulfillment of the requirements for the degree of Master of Science." / Advisor: James B. Cowart, Professor Directing Thesis. / Includes bibliographical references (leaves 163-165).

Thesis (Ph. D. in Soil Science)--University of California, Berkeley, 1995. / Includes bibliographical references (leaves 110-126).

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisors: Mukul M. Sharma and Gary A. Pope. Vita. Includes bibliographical references. Available also from UMI Company.

Hyporheic flow influences both biogeochemical cycling in streambeds as well as streambed ecology. Some biogeochemical processes may be temperature dependent; therefore, heat transport associated with hyporheic flow may be an important influence on such cycles. I separately and experimentally assessed the effects of hyporheic flow due to bed topography on thermal dynamics in the sediment using a custom, tilting flume with temperature controls. Diel temperature cycles of 6° C were imposed in the flume and propagation of temperature signals into the sediment was examined for different bed morphologies (plane bed, pool-riffle-pool, and rippled bed), channel flow rates, and sediment grain sizes. Temperature fields in the sediment were monitored using an array of embedded thermistors, and this data was used to identify zones of upwelling and downwelling within the hyporheic zone. Results suggest that bedforms do induce substantially deeper downwelling upstream and downstream of the bedforms, with upwelling near the crest. This in turn leads to substantial advective heat transport and distinct thermal patterns in the sediment. Variation in permeability and channel flow rates further affects the magnitude of this advective transport. These results corroborate existing theoretical models of coupled hyporheic exchange and heat transport under bedforms. Hyporheic flow therefore affects thermal patchiness in sediment, which may in turn exert a control on biogeochemical reaction rates, and form thermal refugia for fauna. / text