Petrologic and Mineral Physics Database for use with the USGS National Crustal Model - Data Release

We present a petrologic and mineral physics database as part of the USGS National Crustal Model (NCM) for the western United States. Each of 209 geologic units, 134 of which are currently part of the geologic framework within the NCM, is assigned a mineralogical composition according to generalized classifications with some refinement for specific geologic formations. The mineral physics database builds off of previous work to include several minerals specific to continental rock types. We explore the impact of this database on zero-porosity anharmonic P- and S-wave rock velocities and density relative to a well-used empirical study by Brocher (2005) and find that empirical relations between P-wave velocity and S-wave velocity or density do well on average but can differ from mineral physics calculations by up to 15% in S-wave velocity and almost 40% in density. This is consistent with Brocher's study where he obtained similar results for in-situ measurements and laboratory rock specimens.