Detailed Analysis of Microseismic Activity Associated with Shutdowns of the San Emidio Geothermal Plant, Nevada
Description:
We are analyzing dense seismic array data encompassing shutdowns of the San Emidio geothermal plant in Nevada in 2016 and 2022. In 2016, an array of ~1,300 vertical-component seismographs operated by Microseismic Inc. recorded for about a week. In 2022, an array of 450 three-component seismographs was deployed as part of the WHOLESCALE project, covering most of the northern ~2/3 of the 2016 array footprint at twice the instrument spacing, and recorded for about a month. The data are being analyzed with two workflows to detect and locate the microseismic events. The first generates a microseismic event catalog directly from the raw continuous seismic data. The second produces high-precision event locations via a sequence of repicking arrivals, waveform cross-correlation, and double-difference relocation. Analysis of the 2022 data set reveals intense seismic activity commencing soon after shutdown and returning to the previous background rate shortly after restart. The events fall into several main clusters that include some linear features. Preliminary results for the 2016 data set show a similar pattern of heightened activity during the shutdown, revealing an order of magnitude more events than a previous catalog estimated using a back-projection approach. As the catalog size allows, statistic-physics models analyzing space-time connections as well as magnitude clustering are explored.
The work presented herein has been funded in part by the Office of Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy, under Award Numbers DE-EE0007698 and DE-EE0009032. The seismic instruments deployed in 2022 were provided by the Incorporated Research Institutions for Seismology (now the EarthScope Consortium) through the PASSCAL Instrument Center at New Mexico Tech. Data collected will be available through the EarthScope Data Management Center. The facilities of the EarthScope Consortium are supported by the National Science Foundation’s Seismological Facility for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1724509.
Session: Induced Earthquakes: Source Characteristics, Mechanisms, Stress Field Modeling and Hazards - III
Type: Oral
Date: 5/1/2024
Presentation Time: 02:00 PM (local time)
Presenting Author: Clifford
Student Presenter: No
Invited Presentation:
Authors
Clifford Thurber Presenting Author Corresponding Author cthurber@wisc.edu University of Wisconsin–Madison |
Hao Guo hao.guo@wisc.edu University of Wisconsin–Madison |
Erin Cunningham cunningham.erin4@gmail.com Oak Ridge National Laboratory |
Steven Roecker roecks@rpi.edu Rensselaer Polytechnic Institute |
Jesse Hampton jesse.hampton@wisc.edu University of Wisconsin-Madison |
Neal Lord lord@geology.wisc.edu University of Wisconsin-Madison |
Peter Sobol psobol@wisc.edu University of Wisconsin-Madison |
Kurt Feigl feigl@wisc.edu University of Wisconsin-Madison |
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Detailed Analysis of Microseismic Activity Associated with Shutdowns of the San Emidio Geothermal Plant, Nevada
Category
Induced Earthquakes: Source Characteristics, Mechanisms, Stress Field Modeling and Hazards