Ian Stone Erin A. Wirth alex grant Julia Grossman Arthur D. Frankel 20260127 tabular digital data https://doi.org/10.5066/P1LOPVED Ian Stone Erin A. Wirth alex grant Julia Grossman Arthur D. Frankel 20260401 publication This dataset consists of 3-component acceleration timeseries that describe ground shaking from simulated Mw6.5+ earthquakes on the Seattle, Tacoma, and southern Whidbey Island faults in Washington State. These were produced in support of the development of simulation-based scenario ShakeMaps, as described in Stone et al. (2026). Individual scenarios span a variety of different source parameters (hypocenter location, slip distribution, magnitude, dip direction). These were run within a regional-scale model domain with 0-1Hz resolution that covers most of northwest Washington. These low-frequency seismograms were amended with high-frequency (1-10Hz) stochastic seismograms to produce the broadband timeseries. Timeseries were produced on a regular grid of stations spaced at 1km. Timeseries data are saved in HDF5 format. Please refer to the publication Stone et al. (2026) (as well as Stone et al. (2025)) for additional technical details on the simulations and a corresponding analysis of the results. This data release contains the timeseries data from 60 individual simulations, the corresponding pseudo-spectral accelerations, source files, a Jupyter Notebook with an example of how to open and manipulate the data, and a document describing data formatting. Simulations were conducted to model the wavefield and maximum shaking parameters from potential large earthquakes on the Seattle, Tacoma, and southern Whidbey Island faults. These were used to produce simulation-based scenario ShakeMaps. Simulation outputs may be used to estimate potential peak shaking parameters (peak ground velocity, spectral acceleration) throughout Washington State’s Puget Lowland, as well as investigate seismic source, path, and site effects unique to the region. Please refer to the publication Stone et al. (2026) (as well as Stone et al. (2025)) for a detailed discussion of the range of data applicability (e.g., maximum modeled frequencies, comparisons to empirical ground motion model estimates, etc.). Data represent simulated wavefields of potential future earthquakes. 20250601 See Supplemental Info Complete None planned -123.6841 -121.6296 49.0018 46.8677 ISO 19115 Topic Category biota None ShakeMap seismic hazard earthquake ground motion wavefield simulation earthquake simulation washington state Seattle seismology natural hazards scenario Tacoma USGS Metadata Identifier USGS:692f491bd4be026ff273ac3c None Washington Everett Bellevue Tacoma Olympia Common geographic areas Seattle Pacific Northwest No access constraints. Please see 'Distribution Information' for details. These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Ian P Stone USGS - SOUTHWEST REGION Res Geophysicist mailing and physical

University of WA,Dept of Earth & Space Sciences

Box 351310 Rm 70 Johnson Hall

Seattle WA 98195 USA 205-602-2439 istone@usgs.gov No formal attribute accuracy tests were conducted No formal logical accuracy tests were conducted Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Low frequency (0-1Hz) simulation data were generated using the software SPECFEM3D Cartesian. Initial steps involved specifying a seismic velocity model to represent the 3-D seismic velocity structure in western Washington State; developing finite fault source models to represent rupture on the Seattle, Tacoma, and southern Whidbey Island faults; and building a model mesh to discretize the seismic wavefield. High frequency (1-10Hz) simulation data were generated using the software SMSIM. Initial steps involved determining 1D velocity profiles for each site, as well as source and attenuation characteristics. The high and low frequency components of the seismogram were combined using a matched filter method at 1Hz. Simulations represent two minutes of shaking during and following large earthquakes on the Seattle, Tacoma, and southern Whidbey Island faults. The simulation data presented here are three-component (EW/NS/UP) acceleration (m/s/s) timeseries sampled at 40Hz. The corresponding pseudo-spectral accelerations (SA) are calculated as the response of a 5% critically damped, single-degree-of-freedom oscillator. The values represent the median SA response between the 2 horizontal components (i.e., RotD50) and are in units of G. Station locations are in UTM Zone 10 coordinates. 20260401 Universal Transverse Mercator 10T 1 0 0 0 0 coordinate pair 1 1 meters swif_M7_1_1_mid_regional_stochastic.h5 Each simulation file has 4 global attributes, including DATETIME, a time string (in UTC) recording the start of the simulation; UNIT, the unit for the data (“m/s/s” for all simulations here); DELTA, the sample interval in seconds; and ORIGINTIME, the origin time in seconds, relative to the start time of the simulation and the earliest source (0s for all simulations here). Timeseries data are saved in groups corresponding to stations. In each group, data include the number of samples in the timeseries (NPTS); a flag for whether the simulation coordinates are faithful to geographic coordinates (ISNSEW); the true latitude/longitude/depth (or UTMN/UTME/depth) of the stations (STLA/STLO/STDP); and the location of the station within the simulation domain (STX/STY/STZ)(will be the same as STLA/STLO/STDP if ISNSEW is True). The timeseries data are named X, Y, Z or EW, NS, UP depending on the ISNSEW flag. Each component is also assigned an azimuth (*CMPAZ) and inclination (*CMPINC), corresponding to the azimuth of the component clockwise from north and inclination relative to horizontal. Producer defined swif_M7_1_1_mid.sou Source files, which are in ASCII format, contain information about the finite fault sources used for each rupture scenario. Data from these files were used to generate input source files for Specfem3D. Each line corresponds to individual subsources within the finite fault source. The columns correspond to the following: -Column 1: UTM northing coordinate -Column 2: UTM easting coordinate -Column 3: Depth coordinate in meters (positive downward) -Column 4: Subsource moment in Newton-meters -Column 5: Subsource initiation time in seconds, relative to the start of the simulation -Column 6: Subsource rise-time in seconds -Column 7: Subsource strike in degrees -Column 8: Subsource dip in degrees -Column 9: Subsource rake in degrees Producer defined STATIONS_regional.txt Stations file, which is in ASCII format, contains station names and locations in the regional-scale mesh. Data are formatted for use as Specfem3D STATIONS files. Each line corresponds to a station (i.e., a timeseries recording point) and its location within the model domain. X/Y coordinates in STATIONS_regional.txt denote UTM coordinates in UTM Zone 10T. The columns correspond to the following: -Column 1: Station name -Column 2: Network (dummy variable) -Column 3: Y-coordinate (UTM northing) -Column 4: X-coordinate (UTM easting) -Column 5: Elevation (meters) -Column 6: Burial depth (meters) Producer defined swif_M7_1_1_mid_regional_stochastic.h5 Each pseudo-spectral acceleration (SA) file has one global attribute, UNIT, the unit for the data (“G” for all simulations here). SA data are saved in groups corresponding to stations. In each group, data include the number of periods sampled (NPTS); a flag for whether the simulation coordinates are faithful to geographic coordinates (ISNSEW); the true latitude/longitude/depth (or UTMN/UTME/depth) of the stations (STLA/STLO/STDP); and the location of the station within the simulation domain (STX/STY/STZ)(will be the same as STLA/STLO/STDP if ISNSEW is True). The SA data have associated periods in seconds (PERIOD) and SA values (SPEC_ACC). Producer defined Data in this release include timeseries data saved in HDF5 format, pseudo-spectral acceleration data saved in HDF5 format, source files containing parameters of the modeled earthquake slip distributions, and stations files with station names and locations. Stone, I., Wirth, E.A., Grant, A., Grossman, J., and Frankel, A.D., 2026, Simulation-based scenario ShakeMaps for large magnitude (Mw6.5+) crustal earthquakes on the Seattle, Tacoma, and southern Whidbey Island faults, Washington, USA: U.S. Geological Survey data release, https://doi.org/10.5066/P1LOPVED U.S. Geological Survey - ScienceBase mailing address

Denver Federal Center

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Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P1LOPVED None 20260127 Ian P Stone USGS - SOUTHWEST REGION Res Geophysicist (Mendenhall) mailing and physical

University of WA,Dept of Earth & Space Sciences

Box 351310 Rm 70 Johnson Hall

Seattle WA 98195 USA 205-602-2439 istone@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999