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Title: Modeling the Sevier fault zone, southern Utah: validity testing and 3d analysis
The Sevier fault zone near Orderville, Utah, represents a segmented normal fault system within the transition zone between the Basin and Range Province and the Colorado Plateau. This fault system consists of three primary segments: the Orderville segment, the Spencer Bench segment, and the Mt. Carmel Segment. The interactions between segments led to the development of complex structural geometries exposed along the fault zone. These geometries influence deformation and create fractures that affect expected permeability and fluid flow within the fault zone. These geometries also impact how slip-related energy is dissipated during earthquake-related slip propagation. Therefore, analysis of these geometries has implications for f luid flow and seismic hazard within segmented fault systems. I used the Move2020 software suite by Petex to develop a 3D model of the complexly-segmented Sevier fault zone near the city of Orderville in southern Utah. Earlier researchers’ subsurface interpretations were based on surface mapping rather than direct documentation of subsurface fault and layer geometries, so 3D model development permits validation of hypothesized subsurface structures. I digitized geologic contacts, faults, and stratigraphic horizons based on published geologic mapping and cross-sections to develop a 3D model of the fault network. I confirmed that the model does represent a well-constrained 3D system of the Sevier fault zone based on demonstrated integrity between the digital elevation model (DEM), and all available structural data. This work should provide future researchers with the data necessary to model evolution of the overall fault system, which will permit accurate determination of fault-related fracture development and the most likely fluid flow paths. Furthermore, development of a fully retro-deformable model of the fault zone will allow strain analysis that may help researchers understand how fault segment geometries impact earthquake slip propagation. This determination can be used to provide a conceptual framework for other researchers to better constrain the evolution of segmented fault zones worldwide.  more » « less
Award ID(s):
2042114
PAR ID:
10525510
Author(s) / Creator(s):
;
Corporate Creator(s):
Editor(s):
Davidson, Cam; Wirth, Karl
Publisher / Repository:
Keck Geology Consortium
Date Published:
ISSN:
1528-7491
Format(s):
Medium: X
Location:
Macalester College, St. Paul, MN
Sponsoring Org:
National Science Foundation
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