Erin A. Wirth Alex R. Grant Ian P. Stone William J. Stephenson Arthur D. Frankel 20250616 raster digital data https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/P14HJ3IC Erin A. Wirth Alex R. Grant Ian P. Stone William J. Stephenson Arthur D. Frankel 20250919 publication Open-File Report U.S. Geological Survey Wirth, E.A., Grant, A.R., Stone, I.P., Stephenson, W.J., and Frankel, A.D., 2025, Three-dimensional seismic velocity model for the Cascadia Subduction Zone with shallow soils and topography, version 1.7: U.S. Geological Survey Open-File Report 2025–1045, 18 p., https://doi.org/10.3133/ofr20251045. https://doi.org/10.3133/ofr20251045 This data release contains three netCDF4 files containing grid points of P- and S-wave seismic velocities in Cascadia. This model is an update to Stephenson et al. (2017) Open-File Report 2017-1152, and contains a newly added shallow soil model and optional user-specified topography. A description of the model and its development is provided in the associated Open-File Report. The grid points are given in Universal Transverse Mercator (UTM) Zone 10T, and the grid point depths are given in meters below sea level. The model region extends approximately from 40.2°N to 50°N latitude, and from 121°W to 129°W longitude. The maximum depth of the model region is 59,400 meters. The netCDF4 files range in size from approximately 750 megabytes to 6.2 gigabytes. Water offshore the Pacific Coast is assigned a value of -999 for both the P- and S-wave velocities. This 3-D seismic velocity model for Cascadia was primarily developed for earthquake ground motion simulations focused on the U.S. Pacific Northwest. 2024 ground condition Complete None planned Cascadia Subduction Zone -129.0000 -121.0000 50.0000 40.2000 USGS Thesaurus seismology USGS Metadata Identifier USGS:65b40c6ad34e36a390458d76 None Cascadia Subduction Zone U.S. Pacific Northwest None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Erin A. Wirth U.S. Geological Survey physical

4000 15th Ave NE

Seattle WA 98195 206-685-7563 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. No formal positional accuracy tests were conducted No formal positional accuracy tests were conducted William J. Stephenson 2017 dataset https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/f7ns0swm Digital and/or Hardcopy 20171217 publication date Open-File Report 2017-1152 Original P- and S-wave velocities Refer to the associated publication 2024 Universal Transverse Mercator 10 0.9996 -123.0 0 500000 0 row and column Variable Variable meters Mean sea level 10 100 300 900 meters Attribute values CVM17_L3 Vp and Vs values with a grid spacing of 900 m (horizontal) and 900 m (vertical) from 10800-59400 m depths Producer Defined utme Easting coordinate in UTM Zone 10 Producer Defined -10800. 642600. meters 900. utmn Northing coordinate in UTM Zone 10 Producer Defined 4467300. 5540100. meters 900. z Depth below sea level Producer Defined 10800. 59400. meters Vp P-wave velocity Producer Defined 5159. 8463. meters per second Vs S-wave velocity Producer Defined 3081. 4813. meters per second CVM17_L2 Vp and Vs values with a grid spacing of 300 m (horizontal) and 300 m (vertical) from 1500-9900 m depths Producer Defined utme Easting coordinate in UTM Zone 10 Producer Defined -10800. 643200. meters 300 utmn Northing coordinate in UTM Zone 10 Producer Defined 4467300. 5540400. meters z Depth below sea level Producer Defined 1500. 9900. meters vp P-wave velocity Producer Defined -999. Water Producer defined 2342. 7981. meters per second vs S-wave velocity Producer Defined -999. Water Producer defined 1174. 4540. meters per second CVM17_L01 Vp and Vs values with a grid spacing of 200 m (horizontal) and: 10 m (vertical) from 0-100 m depths (Layer 0) or 100 m (vertical) from 200-1200 m depths (Layer 1) Producer Defined utme Easting coordinate in UTM Zone 10 Producer Defined -10800. 643200. meters 200 utmn Northing coordinate in UTM Zone 10 Producer Defined 4467300. 5540500. meters 200 z Depth below sea level Producer Defined 0 1200 meters vp P-wave velocity Producer Defined -999. Water Producer defined 88 7086 meters per second vs S-wave velocity Producer Defined -999. Water Producer defined 35 3221 meters per second Refer to the associated publication: 'A 3-D Seismic Velocity Model for Cascadia with Shallow Soft Soils & Topography, Version 1.7' INSERT DOI HERE U.S. Geological Survey GS ScienceBase mailing address

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Denver CO 80225 United States 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/P14HJ3IC None 20250923 Erin A. Wirth U.S. Geological Survey physical

4000 15th Ave NE

Seattle WA 98195 206-685-7563 ewirth@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999