Date of Award
1-1-2024
Document Type
Thesis
Degree Name
M.S. in Engineering Science
First Advisor
Ron R. Counts
Second Advisor
Brian Platt
Third Advisor
Gregg Davidson
School
University of Mississippi
Relational Format
dissertation/thesis
Abstract
The Mississippi River Valley Alluvial Aquifer (MRVA) within the Mississippi Embayment (ME) is a crucial freshwater resource in the southern United States, supporting agricultural, municipal, and industrial demands. However, excessive groundwater extraction has led to significant declines in water levels across the region over recent decades. Mississippi River alluvial fans, which emanate from valley walls and overlay the MRVA, are composed of coarse-grained sediments and could be significant groundwater recharge areas for the MRVA. This study focuses on the geology of the Tocowa 7.5-minute quadrangle in northwestern Mississippi, encompassing parts of Panola and Tallahatchie counties, with a goal of understanding the sedimentary architecture and subsurface connectivity of the alluvial fans to the MRVA. A 1:24,000-scaled geologic map was prepared, integrating field mapping with existing borehole data, online aerial imagery, LiDAR-derived Digital Elevation Models (DEMs), and existing online airborne electromagnetic data and new geophysical surveys. Electrical resistivity tomography (ERT) and ground penetrating radar (GPR) were the geophysical techniques used in this mapping. Detailed surficial mapping revealed, from oldest to youngest, the Eocene Zilpha and Kosciusko formations from the Claiborne Group, the Paleogene to Quaternary Upland Gravel Complex, Quaternary slackwater lake deposits, Quaternary loess deposits, and modern alluvium. The study identified and characterized six alluvial fans formed by tributaries of the Yocona River and Little Tallahatchie River within the study area. These fans consist primarily of poorly sorted gravelly sand with alternating lenses of coarse-grained sand, silt, and clay. Borehole data and online airborne electromagnetic data suggest that most of these alluvial fans extend to depths of 45 meters and connected to Paleogene (Tertiary) aquifers.
Recommended Citation
Dahal, Anisha, "Surficial Geologic Mapping of the Tocowa 7.5-Minute Quadrangle, Tallahatchie, and Panola Counties in Northwestern Mississippi: Geologic Framework of Alluvial Fans with Implications for Aquifer Recharge" (2024). Electronic Theses and Dissertations. 3008.
https://egrove.olemiss.edu/etd/3008
Geological map
