A Catalog of Regional Moment Tensors in Utah from 1998 to 2011

Abstract

Online Material: The electronic supplement includes details for all 48 moment tensor solutions in this study, including waveform fits and a table of event parameters. The University of Utah Seismograph Stations (UUSS) operates regional seismic networks in and around Utah and Yellowstone National Park and provides routine earthquake locations and earthquake catalogs for these two areas (Pechmann et al. , 2007). In this study, we expand the reporting to include moment tensors for seismic events occurring in the Utah region (Fig. 1). This region is a complex seismic environment with diverse source types: tectonic earthquakes, mining‐induced seismicity (MIS) including mine collapses, and man‐made sources such as explosions. Most tectonic earthquakes in the region occur within the Intermountain Seismic Belt (ISB; Smith and Arabasz, 1991). In northern Utah, the ISB roughly delineates the boundary between the Basin and Range and the Middle Rocky Mountains, whereas in central and southern Utah, the ISB separates the actively extending Basin and Range from the more stable Colorado Plateau. The MIS is mostly associated with long‐wall coal mining in central Utah (Fig. 1; Arabasz et al. , 2007). The man‐made blasts occur throughout the state and are related to both surface mining operations and military munitions detonations (Arrowsmith et al. , 2008). Figure 1. UUSS Utah monitoring area (dark gray box) and the surrounding region. Solid black line separates the UUmod velocity model regions between Basin and Range to the northwest and Colorado Plateau to the southeast. Dashed line separates physiographic provinces: Basin and Range (BR), Colorado Plateau (CP), and Middle Rocky Mountains (MR). The transition zone is roughly the overlap between the physiographic and velocity model boundaries between the Basin and Range and Colorado Plateau in Central Utah. Crescent‐shaped and rectangular polygons in central‐eastern Utah are coal mining areas. ECSZ is the Eastern California …