Assessment of Legacy Fault Studies and New Geological Mapping: Towards Improving Seismic Hazard Models at Yucca Mountain, Nevada
Description:
Yucca Mountain is a potential geological repository for spent nuclear fuel and other high-level radioactive waste in Nye County, Nevada. Strong ground motions and surface rupture generated by earthquakes are hazards that have the potential to affect the suitability of nuclear waste storage at the site. Due to these hazards, investigations of active faulting were conducted from the late 1970’s to the mid 1990’s by multiple Federal (DOE; USGS) and State (NBMG; NSL) agencies to better characterize seismic sources and define fault rupture parameters necessary for probabilistic seismic hazard assessments. These legacy studies determined that at least eight faults in the immediate vicinity of Yucca Mountain are clearly active seismic sources. However, the experimental age dating techniques and poor quality of imagery available at the time of the studies resulted in large uncertainties in the assessment of fault parameters including the timing of events, slip rates, recurrence intervals, and maximum displacements.
Funded by the Nevada Agency for Nuclear Projects, this 4-year project aims to critically evaluate previous geological mapping and trenching studies at Yucca Mountain based on interpretation of modern satellite and aerial imagery, digital elevation models (DEMs), and lidar (pending). The evaluation will independently assess and critique the data quality and provide potential improvements. Data products will include new Quaternary geologic mapping at 25 previous fault trenching study sites and a quality ranking of the sites. We present the initial geodatabase compilation (legacy maps, imagery, topographic models, etc.) and preliminary mapping at several sites. Later phases of the project will include field verification of the mapping and collection of geochronologic samples to constrain the ages of faulted deposits. The products will be used to prioritize sites for detailed study that will help plan a long-term paleoseismic assessment program aimed at improving seismic hazard models at Yucca Mountain.
Session: Temporally Variable Records of Earthquake Behavior and Considerations for Seismic Hazard Analyse [Poster]
Type: Poster
Date: 4/17/2025
Presentation Time: 08:00 AM (local time)
Presenting Author: Richard
Student Presenter: No
Invited Presentation:
Poster Number: 33
Authors
Richard Koehler Presenting Author Corresponding Author rkoehler@unr.edu University of Nevada, Reno |
Jim Faulds jfaulds@unr.edu University of Nevada, Reno |
Jennifer Vlcan mauldin@unr.edu University of Nevada, Reno |
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Assessment of Legacy Fault Studies and New Geological Mapping: Towards Improving Seismic Hazard Models at Yucca Mountain, Nevada
Session
Temporally Variable Records of Earthquake Behavior and Considerations for Seismic Hazard Analyses