This three-dimensional (3D) seismic velocity model includes a detailed domain covering the greater San Francisco Bay urban region and a regional domain at a coarser resolution covering a larger region. Version 21.1 updates only the detailed domain with adjustments to the elastic properties east and north of the San Francisco Bay. There are no changes to the underlying 3D geologic model or the regional domain seismic velocity model. Version 21.1 of the detailed domain fits seamlessly inside version 21.0 of the regional domain without any jumps in elastic properties across the boundary between the two domains. The model was constructed by assigning elastic properties (density, Vp, Vs, Qp, and Qs) to grids of points based on the geologic unit and depth from the ground surface. The model is stored in HDF5 files using the GeoModelGrids (https://geomodelgrids.readthedocs.io) storage scheme. GeoModelGrids provides a high-level interface for accessing the model. The model can also be accessed using the HDF5 application programming interface provided with many programming languages and tools, but the user will be responsible for all coordinate transformations.

This three-dimensional (3D) seismic velocity model includes a detailed domain covering the greater San Francisco Bay urban region and a regional domain at a coarser resolution covering a larger region. Version 21.0 is a re-release of v08.3.0 in a new storage scheme. The model was constructed by assigning elastic properties (density, Vp, Vs, Qp, and Qs) to grids of points based on the geologic unit and depth from the ground surface. The model is stored in HDF5 files using the GeoModelGrids (https://geomodelgrids.readthedocs.io) storage scheme (see the README.md file for an overview). GeoModelGrids provides a high-level interface for accessing the model. The model can also be accessed using the HDF5 application programming interface provided with many programming languages and tools, but the user will be responsible for all coordinate transformations.

This three-dimensional (3D) seismic velocity model includes a detailed domain covering the greater San Francisco Bay urban region and a regional domain at a coarser resolution covering a larger region. Version 21.0 is a re-release of v08.3.0 in a new storage scheme. The model was constructed by assigning elastic properties (density, Vp, Vs, Qp, and Qs) to grids of points based on the geologic unit and depth from the ground surface. The model is stored in HDF5 files using the GeoModelGrids (https://geomodelgrids.readthedocs.io) storage scheme (see the README.md file for an overview). GeoModelGrids provides a high-level interface for accessing the model. The model can also be accessed using the HDF5 application programming interface provided with many programming languages and tools, but the user will be responsible for all coordinate transformations.

In October 2016, we acquired an approximately 15-km-long seismic profile along a linear transect across the East Bay region of the San Francisco Bay area. Our goal was to image previously unknown strands of the Hayward Fault zone and to better delineate the structure and geometry of the main trace of the Hayward Fault. Our profile started near the southern border of San Leandro, California at the San Francisco Bay shoreline, trended ENE through the northern edge of Castro Valley, California, and ended approximately 5 km WSW of San Ramon, California. The data were analyzed using refraction tomography modeling, reflection processing, and guided-wave analysis. The analyzed data are presented in separate reports by Strayer and others (submitted to BSSA). The seismic data were generated at 26 shotpoints: 16 shotpoints located along the profile (inline shotpoints) and 10 shotpoints offset from the profile and located within known or suspected fault traces (guided-wave shotpoints). Most shotpoints used explosive sources to generate the seismic waves, but three of the shotpoints used repeated hits from a 227-kg (500 lb) accelerated weight dropped ~2 feet above a steel plate to generate the seismic signal. Data from each shot were recorded by a total of 459 seismographs, mostly deployed along the profile at intervals ranging from 20 to 100 meters. This data release contains the raw field records from all explosive and weight drop shots. The raw field records are in a proprietary Trimble TRD format and consist of continuous seismograph recordings during the time of the data collection. Also included in this data release are multiple SEG-Y files consisting of thirty-second-long traces "cut" from the TRD files and resorted into conventional shot gathers. These data are in standard SEG-Y format, with the data samples in IBM floating point format. Data samples are in units of meters/second, without filtering or other data manipulation.

This data release provides a map of the time-averaged shear-wave velocity in the upper 30 m (Vs30) for California using the method described by Thompson and others (2014). There are two adjustments to the algorithm described by Thompson and others (2014), which is built on the geology-based Vs30 map by Wills and Clahan (2006). In this data release, we use the Wills and others (2015) updated geology-based Vs30 map. The second change is that we have adjusted the kriging procedure so that measured Vs30 values do not affect the predictions across distinctly different geologic units.

This data release provides a map of the time-averaged shear-wave velocity in the upper 30 m (Vs30) for California using the method described by Thompson and others (2014). There are two adjustments to the algorithm described by Thompson and others (2014), which is built on the geology-based Vs30 map by Wills and Clahan (2006). In this data release, we use the Wills and others (2015) updated geology-based Vs30 map. The second change is that we have adjusted the kriging procedure so that measured Vs30 values do not affect the predictions across distinctly different geologic units.

The California Geological Survey published maps of “Earthquake Shaking Potential for California” in 1999 and has revised the maps following each update of the National Seismic Hazard Maps (NSHM). Similar to the NSHMs, the Earthquake Shaking Potential Maps for California depict expected intermediate period (1s or 1hz) ground motions with 2% exceedance probability in 50 years. Unlike the NSHMs, Earthquake Shaking Potential Map for California incorporates anticipated amplification of ground motions by local soil conditions. The current update of the Earthquake Shaking Potential Map for California (California Geological Survey Map Sheet 48) is based on the 2014 NSHMs developed by the United States Geological Survey (Petersen et al., 2014), a new map of the average shear wave velocity in the upper 30m of the earth’s surface for California (Wills et al., 2015), and a new semi-empirical nonlinear site amplification model (Seyhan and Stewart, 2014).

The California Geological Survey published maps of “Earthquake Shaking Potential for California” in 1999 and has revised the maps following each update of the National Seismic Hazard Maps (NSHM). Similar to the NSHMs, the Earthquake Shaking Potential Maps for California depict expected intermediate period (1s or 1hz) ground motions with 2% exceedance probability in 50 years. Unlike the NSHMs, Earthquake Shaking Potential Map for California incorporates anticipated amplification of ground motions by local soil conditions. The current update of the Earthquake Shaking Potential Map for California (California Geological Survey Map Sheet 48) is based on the 2014 NSHMs developed by the United States Geological Survey (Petersen et al., 2014), a new map of the average shear wave velocity in the upper 30m of the earth’s surface for California (Wills et al., 2015), and a new semi-empirical nonlinear site amplification model (Seyhan and Stewart, 2014).

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This dataset complements the following publication: Goldberg, D.E. & Haynie, K.L (2021) Ready for Real-Time: Performance of Global Navigation Satellite Systems in 2019 Mw7.1 Ridgecrest, California, Rapid Response Products, Seismological Research Letters, doi: 10.1785/0220210278. The availability of low-latency, high-rate Global Navigation Satellite Systems (GNSS) waveforms makes it possible to compute joint seismic and geodetic finite-fault models of significant earthquakes (typically M 6.0 or larger) using regional data (i.e. from strong-motion accelerometers and real-time GNSS). Notably, real-time GNSS displacement data has reduced accuracy when compared to post-processed displacements, due to inherent challenges in estimating satellite clocks and orbits in real-time (see associated manuscript for details). Here, we present the results of joint strong-motion accelerometer and GNSS finite-fault inversions for the 2019 Mw7.1 Ridgecrest, California earthquake. We compare the results of the joint inversions that use post-processed GNSS to those making use of real-time GNSS displacements. Real-time GNSS displacements come from two different processing facilities: UNAVCO and Central Washington University (CWU). Two different weighting schemes (uniform and data norm weighting) are applied, resulting in a total of six joint inversions. A figure showing these six models is included here ("Finite-Fault Model Results") and is a reproduction of Figure 3 of the associated manuscript listed above. The inversion results are provided as text files with titles corresponding to their GNSS data processing type and the inversion data weighting scheme (e.g., "Strong-Motion and CWU Real-Time GNSS (Uniform Weight)." Please see the associated manuscript listed above for details about the GNSS processing types and weighting schemes applied. A summary table comparing the six models (above) and the USGS teleseismic inversion (https://earthquake.usgs.gov/earthquakes/eventpage/ci38457511/finite-fault) is titled "Finite-Fault Model Comparison Summary". The resulting models are also used to create an estimate of the source dimensions as input to the USGS ShakeMap ground motion estimates. Estimated source dimension information is available in the table titled "Source Dimension Estimates for ShakeMap".