San Francisco Bay region 3D seismic velocity model v21.0

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.