Thesis (Ph. D.)--Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution, 1982. / Vita. Includes bibliographical references (p. 217-223).

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 143-158).

Thesis (M.S.)--Oregon State University, 1977. / Typescript (photocopy). Date thesis presented: June 3, 1976. Includes bibliographical references. Also available on the World Wide Web.

The objective of this research is to identify the circulation patterns of the water and sediment fluxes in coastal and estuarine zones, where the shoaling processes correlate with tide generating flow patterns. The research provides a better understanding of the characteristics of spatial and temporal variability of currents. An important deviation from previous research is the inclusion of the baroclinic term, which becomes very important in density driven flows. The understanding of this process provides a basis for determining how the water circulation three-dimensionally controls the hydrodynamics of the system and ultimately transports the suspended and soluble materials due to combined currents and waves. A three-dimensional circulation model is used to calculate the water circulation. The model is based on the three-dimensional (3D) version of Advanced Circulation (AD-CIRC) Hydrodynamic Model with extending the Sediment Transport module. The model is based on the finite element method on unstructured grids. The output of the hydrody-namic model is used to estimate spatial and temporal advections, dispersions and bottom shear stress for the erosion, suspension, deposition and transport of sediment. The model development includes extending the existing three-dimensional (3D) ADCIRC Model with (1) baroclinic forcing term and (2) transport module of suspended and soluble materials. The transport module covers the erosion, material suspension and deposition processes for both cohesive and non-cohesive type sediments. The inclusion of the baroclinic demonstrates the potential of over or underpredicting the total net transport of suspended cohesive sediment under influence of currents. The model provides less than 6% error of theoretical mass conservation for eroded, suspended and deposited sediment material. The inclusion of the baroclinic term in stratified water demonstrates the prevailing longshore sediment transport. It is shown that the model has an application to the transport of the cohesive sediments from the mouth of the Mississippi River along the north shore of the Gulf of Mexico towards and along the Texas coast. The model is also applicable to determine the design erosion thickness of a cap for isolating contaminated dredged material and to evaluate the appro-priate grain size of cap sediments to minimize the erosion.

Since 1970, U.S. Army Corps of Engineers, Galveston District, has been using dredged sediments from the Houston ship channel to create and restore salt marshes in Galveston Bay. Some projects have failed due to excessive sediment erosion or siltation. The research reported here applies an engineering approach to analysis of tidal creeks in natural and beneficial use marshes of Galveston Bay. The hydrodynamic numerical model, DYNLET, was used to assess circulation in marsh channels. A preliminary sediment transport model was developed to analyze erosion and deposition for the same channels. In situ flume experiments were conducted to determine the sediment erodibility in natural and constructed marshes. A natural reference marsh, Elm Grove, was studied to understand marsh hydrodynamics and model calibration. The model results show that DYNLET can largely duplicate the marsh hydrodynamics and the sediment transport model can provide preliminary indication of erosion in tidal creeks. Analysis of the preliminary channel layout of the beneficial-use marsh demonstrated that channels will have sufficient circulation and optimum velocities.

Thesis (M. Sc.)--College of William and Mary. / Typescript (photocopy). Vita. Includes bibliographical references (leaves 96-100).

Thesis (Ph.D.), Memorial University of Newfoundland, 2000. / Restricted until June 2001. Bibliography: leaves 183-193. Also available online.

Thesis (Ph. D.)--Rutgers University, 2008. / "Graduate Program in Environmental Sciences." Includes bibliographical references.

Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 174-185). Also available in electronic version. Access restricted to campus users.

This dissertation presents an investigation of the effects of a stochastic component of sediment transport in sandy rivers in an attempt to gain information about the transport system and its implications for the evolution of Earth's surface topography. First, a method for characterizing the geometries of bed forms is introduced and compared to previously proposed methods. This new method is then implemented on a field dataset as well as laboratory dataset and the results are compared to those obtained by traditional methods. Second, a method for characterizing the dynamic evolution of the bed geometries is demonstrated. It produces a velocity scale, the mean migration rate of the bed topography, and a deformation scale, the evolutionary departures of the bed topography from pure migration. These scales are calculated for the field and laboratory data and are compared. The flux of bed sediment is then shown to depend on the stochastic component of bed evolution. The fluxes for each dataset are calculated, they are related to the environmental conditions causing the transport of sediment, and suggestions are made for the design of field campaigns that attempt to measure sediment transport by repeated surveys of bed topography. Finally, the implications of stochasticity for sediment transport are investigated. A null hypothesis is formulated for topographic change by a stochastic process. Then the effects of measurement and field collection methods on the null hypothesis are evaluated. The most important prediction is non-trivial behaviors in measurable rates of surface change at short timescales. This prediction is then evaluated with field data from a growing sandy channel network whose behaviors can be determined at timescales of decades to centuries (dendrochronology), tens of thousands of years (cosmogenic radiochemistry), and hundreds of thousands to millions of years (age of channel system and sediments through which it cuts). These three investigations create a coherent account of the expressions and implications of variability in the transport of sediment, and therefore the evolution of topography, in sandy river systems that can then be generalized to changes across Earth's surface. / text