| Description |
A proposed site for the Department of Energy's Frontier Observatory for Research in Geothermal Energy (FORGE) is located in southwestern Utah, in the Milford Basin, west of the Mineral Mountains. This site is at the intersection of the Intermountain Seismic Belt and the Pahranagat Shear Zone. This area is known for geothermal energy and the Roosevelt Hot Springs power plant, east of FORGE, has been active since 1984. For FORGE to be successful, an induced seismicity mitigation plan is required. There have been 185 seismic events from 1850 to 2016 cataloged by the University of Utah Seismograph Stations (UUSS) in this area. In this study, I completed a noise analysis on the local seismometers IMU, NMU, and DWU and determined the capabilities for the seismic detection work. To lower the magnitude of completeness, subspace detection analysis was applied for the years 2010-2016 and the best events were relocated in a relative sense together with events from the UUSS catalog. The relocated events were analyzed through principal component analysis to determine their hypocentral geometric distribution. Within the study area, we determined a new potential fault just north of Milford, Utah and observed hypocentral geometries in the Mineral Mountains that are consistent with previously reported tectonic structures. Finally, with the additions to the UUSS catalog and completed work, we were able to complete a stability analysis to show that we successfully reduced the magnitude of completeness for the area during the time period of 2010-2016. These results have allowed a seismicity baseline to be established for the induced seismicity mitigation plan for FORGE. |
