Structural Geology of The Brady Mountain Area, Ouachita Mountains, Arkansas: Integrating Field Mapping, Geospatial Techniques, Photogrammetry And 3D Modeling For Structural Analysis

Author

• Emmanuel Darko, Stephen F Austin State UniversityFollow
• Zachariah Fleming, Stephen F Austin State UniversityFollow

Date of Award

Fall 12-2025

Degree Type

Thesis

Degree Name

Master of Science - Geology

Department

Geology

First Advisor

Dr. Zachariah Fleming

Second Advisor

Dr. R. LaRell Nielson

Third Advisor

Dr. Liane Stevens

Fourth Advisor

Dr. Jenny Rashall

Abstract

Much of the Ouachita orogenic belt, representing the deformed Paleozoic rocks flanking the southern margin of the North American craton, is buried beneath post-orogenic Mesozoic and Tertiary sediments composing the Gulf Coastal Plain. The Ouachita Mountains of Arkansas and Oklahoma are the largest areas of outcrop for the Pennsylvanian-age Ouachita orogenic belt, making it an ideal place to study the orogeny. This study focuses on the Brady Mountain area within the Benton Uplift, the orogenic core of the Ouachita Mountains in western Arkansas. The region is comprised of numerous ridges trending nearly east-west and are for the most part densely wooded and separated from one another by cultivated flood plains. Outcrops appear sparse but are numerous along the stream bottoms, creeks and along many road cuts, with significant exposures of predominantly Ordovician formations.

The sequence consists of fine-grained clastic units, including the shales of the Womble and Mazarn formations, the Blakely Sandstone and the quartzose, carbonate-cemented Crystal Mountain Sandstone. Structural complexity of the area is evident in the folds, faults, and fractures in outcrops. Folds in the study area are generally trending east-west and, in some cases, are overturned with a southern vergence. Faulted folds, fractures, and cleavages offer independent evidence that the ductile regime was succeeded by a more brittle deformation. The primary goal of this study is to geologically map the structure of the Brady Mountain area to better understand the deformation and tectonic influences on the Paleozoic strata of the Ouachita Mountains.

This study also incorporates digital techniques, including the use of LIDAR and photogrammetry, to address difficulties presented by densely vegetated areas. LIDAR is particularly valuable, as it penetrates forest and vegetation canopies, allowing for detailed analysis of the map area. Photogrammetric models will be used for detailed analysis of select outcrops so that field time can be optimized and, additionally, provide a more immersive data product from this project. Finally, MOVE software will be used to create a 3D model of the map area, allowing comprehensive spatial visualization and analysis of structural relationships.

Repository Citation

Darko, Emmanuel and Fleming, Zachariah, "Structural Geology of The Brady Mountain Area, Ouachita Mountains, Arkansas: Integrating Field Mapping, Geospatial Techniques, Photogrammetry And 3D Modeling For Structural Analysis" (2025). Electronic Theses and Dissertations. 662.
https://scholarworks.sfasu.edu/etds/662

Creative Commons License

This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.