Paper No. 266-4
Presentation Time: 9:00 AM-6:30 PM
DEVELOPMENT OF COMPARATIVE TECTONIC MODELS USING STRUCTURAL AND PETROGRAPHIC APPLICATIONS TO GEOLOGIC MAPPING
The Arbuckle Mountains in south-central Oklahoma exhibit structurally complex stratigraphy associated with features like the Southern Oklahoma Aulacogen, the Arbuckle and Hunton Anticlines, and corresponding subsiding rift basins, as well as numerous faulting networks like the Washita Valley fault zone. Camp Classen YMCA and Turner Falls Park (Davis, OK) host observed, but unmapped, small scale structural features that best represent the magnitude of regional deformation. Deformation in these areas is likely associated with the Washita Valley fault zone. Preliminary field work suggested that the time of faulting was much sooner than originally thought. Mapping these faults and structural features has produced a tectonic model that can be compared to the regional model. The goal of this study is to determine if the complicated small scale structural features at Camp Classen and Turner Falls can be explained by the larger tectonic pattern already attributed to the area. The main faulting in this zone has left-lateral strike-slip movement with series of associated stepover faults. The potential presence of a negative flower structure provides new interpretations for the tectonic timeline. Highly detailed geologic maps reveal the spatial continuity and characteristics of geologic units expressed on the surface. Differentiating geologic units proved difficult due to similarities in exposed marine carbonates so a series of insoluble residues tests were conducted to classify each unit. Additionally, petrography was utilized to validate each unit classification and study the depositional history of the area. Initial examination of orthophotography suggested the gross lithology for the area so a spatial decision support system (SDSS) was created to highlight these areas. Traditional mapping techniques were utilized in conjunction with Midland Valley Fieldmove and Move 3D modeling. This allowed for the most accurate interpretation of the surface and subsurface geology. Stereonet 9 was used to create rose diagrams and stereonets, which aid in classifying and determining the locations and types of folds, faults, and joints. These data have been compared to the existing regional tectonic model constructed by Ham et al. (1975), yielding new potential interpretations and a modified tectonic history of the region.