DOI: 10.5066/p9awinwz
title: Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western U.S.) (ver. 3.0, December 2023)

description: This Data Release contains version 3.0 of two related earthquake geology databases for use in the 2023 U.S. National Seismic Hazard Model. The databases are: 1) A fault sections database (“NSHM23_FSD_v3”), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) an earthquake geology site information database (“NSHM23_EQGeoDB_v3”), which contains fault slip rate constraints at points. These databases cover the 12 western U.S. states: Washington, Oregon, California, Idaho, Nevada, Arizona, Montana, Wyoming, Colorado, New Mexico and Texas. Datasets containing crustal fault information for Alaska and the central and eastern United States were prepared by Bender and others, 2021 and Thompson Jobe and others, 2023 in separate efforts.

The two databases are broken into separate child items from this landing page. The databases are provided as geospatial data (.SHP, .KML, & GeoJSON file formats) and tables (.CSV format). Reference information, including change log, version notes, and a README, are included as "Attached Files" below this Summary. 

Versioning
These databases are updated as of December 2023 (version 3.0), which supersede the databases release in February 2022 (version 2.0) and the January 2021 (version 1.0) preliminary datasets. After significant testing by many user groups, this version 3.0 data release contains minor changes. The specific changes made in the fault sections database (FSD) from version 2.0 (2022) to version 3.0 (2023; this release) are outlined in "NSHM23_FSD_v2-v3_VersionChanges.txt." The changes to the EQGeoDB involve fixing typos and further populating the reference list to include UCERF3 references; the authors acknowledge Scott Marshall (Appalachian State University) for uncovering these additional references. 

Note on the Cheraw fault:
At the time of original compilation (2020-2021), the Cheraw fault of Colorado was included in the western U.S. fault sections database. During model implementation, the Cheraw fault was instead treated as a central and eastern U.S. fault. To maintain consistency with earlier releases, we retain the Cheraw fault geometry and attributes in this table. For more information, please review Shumway and others., in press manuscript about CEUS fault implementation. 

For more information on how these datasets were compiled, please refer to our manuscript publication, Hatem and others, 2022.

References Cited
Bender, A.M., Haeussler, P.J. and Powers, P.M., 2021, Geologic inputs for the 2023 Alaska update to the U.S. National Seismic Hazard Model (NSHM) (ver. 2.0, February 2023): U.S. Geological Survey data release, https://doi.org/10.5066/P97NRR0F
 
Hatem, A.E., Collett, C.M., Briggs, R.W., Gold, R.D., Angster, S.J., Field, E.H., Powers, P.M. and the Earthquake Geology Working Group, 2022, Simplifying complex fault data for systems-level analysis: Earthquake geology inputs for US NSHM 2023. Scientific data, 9(1), 506. https://doi.org/10.1038/s41597-022-01609-7
 
Shumway, A.M., Petersen, M.D., Powers, P.M., Toro, G., Altekruse, J. M., Herrick, J.A., Rukstales, K.S., Thompson Jobe, J.A., Hatem, A.E., and Girot, D.L., in press, Earthquake Rupture Forecast Model Construction for the 2023 U.S. 50-State National Seismic Hazard Model Update: Central and Eastern U.S. Fault-Based Source Model. Seismological Research Letters.
 
Thompson Jobe, J.A., Hatem, A.E., Gold, R.D., DuRoss, C., Reitman, N.G., Briggs, R.W., and Collett, C.M., 2022, Earthquake geology inputs for the National Seismic Hazard Model (NSHM) 2023 (central and eastern United States), version 1.0: U.S. Geological Survey data release, https://doi.org/10.5066/P94HLE5G