Arizona Geological Society
2023 Speaker Series
Tuesday, 3 October 2023 | 5:30 - 8:00 PM
Location: Hexagon Mining Division Office
40 East Congress Street, Suite 150, Tucson, Arizona 85701
Parking: On the street or parking garage (Old Pueblo Parking)
Social Hour with Sandwiches from Beyond Bread (5:30-6:30 PM) Presentation (6:35 PM)
Video - https://www.youtube.com/watch?v=71cZW3qHa4s
The Arizona Geological Society thanks Freeport-McMoRan
for Sponsoring the October 2023 Meeting
The Arizona Geological Society also thanks Hexagon
for generously providing the venue and drinks
Structural Modeling for Reducing Uncertainty in Geologic Interpretations
Amanda Hughes Ph.D.
Assistant Professor of Practice, Department of Geosciences, University of Arizona
Abstract: Geologists are often faced with the challenge of creating a complete interpretation for folds, faults, and fractures with data that are sparse and often ambiguous. This often gives rise to multiple interpretations in some areas; these often have critical implications for practical decision-making in fields as wide-ranging as mineral and petroleum exploration and production, geothermal systems, seismic hazard assessment, and subsurface storage applications. Various modeling approaches have been developed to apply quantitative constraints and reduce uncertainty to the process of geologic cross section and 3D model construction, including kinematic modeling, analog modeling, and numerical mechanical modeling approaches, including finite-element, distinct-element, and boundary-element models. Each of these approaches have different strengths and drawbacks and therefore are most useful in different geologic circumstances; BEM models, for example, are most applicable to low-strain geologic settings, while more highly strained rocks would be more accurately modeled with other approaches.
I will review the various types of modeling approaches currently employed by structural geologists, along with their benefits and disadvantages, and will then show a series of case studies where we have used these approaches to gain insight into the geometry and distribution of stress and strain in various geologic settings. First, I will show the utility of applying boundary element mechanical models to predicting the distribution of stress and fractures around salt bodies in the Paradox Basin in Utah. Then, I will show how kinematic models can be used to constrain cross section interpretations using both surface geology , seismic reflection, and seismicity datasets from several case study locations in Utah, California, and offshore sedimentary basins. I will highlight how our recent work to make these kinematic modeling approaches more flexible and consistent with results from high-strain mechanical models allows them to be applicable and more easily applied to interpreting a wider range of geologic structures. By doing so, I will show how integrating concepts and tools across these various approaches can help to improve our ability to constrain and test geologic models of the subsurface for a range of applications.
Bio: Amanda Hughes is an Assistant Professor of Practice in the Department of Geosciences at the University of Arizona. She holds B.S. degrees in Geology (2006) from Washington and Lee University and M.A. (2009) and PhD. (2012) degrees in Earth and Planetary Sciences from Harvard University. She also has experience working in energy exploration and R&D for Chevron Energy Technology Company (2012-2016). She teaches courses at the University of Arizona in Physical Geology, Structural Geology, Active Tectonics, Exploration Seismology, and Advanced Structural Geology Methods, and co-teaches professional courses on Structural Geology for Mine Geologists and Structural Geology for Geotechnical Professionals. Her research is focused on understanding the growth of geologic structures through integrated observations from field geology, active tectonics, seismology, geophysics, rock mechanics and various modeling approaches. She is also interested in developing and testing new quantitative approaches to observing and modeling geologic structures, and applying these methods to geologic problems in energy and mineral exploration, seismic hazard assessment, and regional tectonics.
Hexagon Mining Division Office - 40 East Congress Street,
Suite 150, Tucson, Arizona 85701
