In Louisiana, barrier islands are undergoing morphological change driven by high rates of relative sea-level rise and interior wetland loss. Previous works utilized historical region-scale bathymetry and shoreline change analyses to assess coastal evolution. However, more localized assessments considering the role of sediment transport processes in regional evolution are lacking. This is essential to predicting coastal change trajectories and allocating limited sand resources for nourishment. Using bathymetric and shoreline data, 100-m spaced shore-normal transects were created to track meter-scale elevation change for 1880s, 1930s, 1980s, 2006, and 2015. An automated framework was used to quantify and track parameters such as shoreline change, barrier island area and width, bathymetric isobath migration, and shoreface slope. Our results illustrate that monitoring subaerial island erosion rates are insufficient for evaluating regional sediment dynamics of transgressive coastal systems. Advances in understanding these processes will facilitate more informed planning, management, and mitigation of transgressive barrier islands.

Thesis (Ph. D.)--Virginia Commonwealth University, 2009. / Prepared for: Dept. of Biology. Title from title-page of electronic thesis. Bibliography: leaves 135-141.

The Grand Bay National Estuarine Research Reserve (GBNERR) adjoins two costal embayments in the eastern Mississippi Sound, Grand Bay and Point Aux Chenes Bay, which encompass a late Pleistocene/ Holocene delta of the Pascagoula-Escatawpa fluvial system. Historical maps and aerial imagery indicate that the GBNERR shoreline has experienced long-term retreat at spatially variable rates. The research presented here investigates the relationship between the coastal geomorphological evolution of GBNERR and the underlying geological framework. Coastal morphology and stratigraphy were characterized by analyzing 85 km of chirp sonar sub-bottom seismic profiles and 45 sediment cores. Shoreline retreat rates were determined through geospatial regression analysis of 11 historical shorelines surveyed between 1850 and 2015. Results indicate that Pleistocene paleochannels in the underlying fluvial distributary ravinement surfaces are spatially correlated with shoreline segments that exhibit elevated retreat rates and should be accounted for in future models of local as well as regional coastal evolution.

Thesis (M.S.)--Mississippi State University. Department of Geosciences. / Title from title screen. Includes bibliographical references.

Thesis (M.S.)--Mississippi State University. Department of Geosciences. / Title from title screen. Includes bibliographical references.

Recent evidence suggests that backbarrier structure may act as an historical record of island development, and that backbarrier shorelines can be used as a proxy of an island’s past and future transgressive response to sea-level rise. The structure and stability of back-barrier shorelines are dependent on the geologic framework, defined here as the combination of nearshore topography, underlying geology, and modern geomorphologic forces. This antecedent framework controls and influences the present morphology, nearshore dynamics, and rates of transgression in response to sea-level rise while also acting as a feedback to the estuary ecology on the bayside. It is therefore surprising that our understanding of backbarrier geomorphology is limited. There is a need for an established link between process regimes and an island’s geomorphological history. This thesis bridges the current intellectual gap. The primary hypothesis of this project is that shorelines and bathymetric isolines share quantitative shape signatures indicative of their shared morphological past. To establish this link, the backbarrier shorelines of four United States National Seashores (Fire Island, NY; Assateague Island, MD; Santa Rosa Island, FL; and North Padre Island, TX) are digitized from aerial imagery using the marshline as the shoreline indicator to ensure the inclusion of (vital, sometimes inundated) ecosystems and sediment storage. The alongshore variation of this backbarrier shoreline, the mainland shoreline, lagoon bathymetry, and nearshore bathymetry are each quantified through wavelet analysis and their shape signatures are examined for spatial correspondence. Large and small scale variations are identified and attributed to the geomorphologic controls operating on the same scale and alongshore variation. The result is an improved understanding of how the geologic framework controls backbarrier shoreline shape, which is essentially an expression of the underlying geology.

Thesis (M.S.)--University of North Carolina Wilmington, 2008. / Title from PDF title page (viewed May 27, 2009) Includes bibliographical references (p. 104-106)

Thesis (M. Sc.)--Memorial University of Newfoundland, 1997. / Blbliography: leaves 278-293.

Thesis (M.S.)--University of North Carolina at Wilmington, 2006. / Includes bibliographical references (leaves: 95-98)

Thesis (Ph. D.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 111-117). Also available on the World Wide Web.