Date of Award
12-2025
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
School
Ocean Science and Engineering
Committee Chair
Dr. Davin Wallace
Committee Chair School
Ocean Science and Engineering
Committee Member 2
Dr. Christopher Hayes
Committee Member 2 School
Ocean Science and Engineering
Committee Member 3
Dr. Mustafa Kemal Cambazoglu
Committee Member 3 School
Ocean Science and Engineering
Committee Member 4
Dr. Rebecca Totten
Committee Member 5
Dr. Kristine DeLong
Abstract
The imprints of past geomorphic evolution are embedded in the geologic record, providing valuable insights into the mechanisms that induce changes within coastal systems and the magnitude of those changes. Large-scale paleo morphodynamic evolution often occurs due to cyclonic activity, variations in sediment supply, and relative sea-level rise. The landscape of the U.S. Gulf Coast reflects a combination of erosional, depositional, hydrological, and climatic factors that remain of ongoing interest to geoscientists seeking a holistic understanding. Low- lying coastal plains, such as those along the Mississippi and Louisiana coasts, are particularly susceptible to future sea-level rise. Projected sea-level rise over the upcoming century (~6-44 mm/yr) aligns with rates observed during the Early Holocene (~4-40 mm/yr). Examining this geological timeframe is crucial for interpreting how similarly vulnerable coastal environments responded in the past. Here, recently collected and legacy datasets—comprising sediment cores, geochemical analyses, and geophysical surveys—have elucidated the geomorphic history of the U.S. Gulf Coast, including the first detailed dating of the transgression from the Early to Mid Holocene in the modern offshore region of the northern Gulf of Mexico. During the Early Holocene, sea levels were lower, resulting in the exposure of the inner shelf. A paleotopographic map illustrating the Pascagoula- Biloxi lowstand valley and a paleoenvironmental reconstruction from 12 ka to 4 ka was developed. The reconstruction yielded a discovery of a paleo wetland that migrated landward 2.7 km, evolving into an ephemeral barrier island-inlet complex along the 20- meter isobath between 10.33 and 10.13 kyr BP, at a rate of 13.6±17.9 m/yr. Additionally, the lowstand Jourdan-Wolf Rivers were mapped through the Mississippi Sound, revealing an incisional valley situated 17-23 meters below sea level, which preserved diverse depositional environments throughout the transgression.
ORCID ID
0000-0001-6323-3440
Copyright
Carrie Miller, 2025
Recommended Citation
Miller, Carrie, "A Line in the Sand: Investigating Late Pleistocene-Holocene Stratigraphy and Large-scale Morphodynamic Evolution Along the Mississippi Coast" (2025). Dissertations. 2408.
https://aquila.usm.edu/dissertations/2408