Building Seismic Safety Council 2014 Event Set
Seismic design codes often are based on a probabilistic seismic hazard analysis and also a deterministic seismic hazard analysis. While a probabilistic analysis accounts for all possible ruptures, a deterministic analysis only considers a representative subset of ruptures that are based on the same models of earthquake sources as the probabilistic analysis. The deterministic subset of ruptures are characteristic earthquakes on all known active faults. This catalog includes the deterministic ruptures from the 2014 version of the USGS national seismic hazard maps.
Ground Motion Models
For a given rupture, the ground motion shaking intensity parameters are computed using a weighted combination of ground motion models for reference rock conditions that is consistent with the 2014 version of the USGS national seismic hazard maps. More details are available in the documentation for the 2014 update of the United States national seismic hazard maps.
We have employed the OpenQuake hazard library (hazardlib) implementation of the ground motion models. OpenQuake hazardlib provides a broad range of well-tested open-source models.
The ground motion parameters in ShakeMap are converted from the average horizontal component, which is given by most ground motion models, to the peak horizontal component. This is necessary for consistency with real-time ShakeMaps. Additional details are discussed in this section of the ShakeMap manual.
The 2014 USGS seismic hazard maps do not account for site response directly. Site conditions are accounted for in the building code separately. However, the scenarios in this catalog include site response in the maps, based on maps of the time-averaged shear-wave velocity in the upper 30 m (Vs30). The input Vs30 grids are a combination of regionally variable models that are available at the USGS Global Vs30 GitHub repository.
This catalog includes ruptures in the coterminous US.
- Building Seismic Safety Council (BSSC) (2015). NEHRP Recommended Seismic Provisions for New Buildings and Other Structures, Volume 1: Part 1 Provisions, Part 2 Commentary, FEMA P-1050-1, Washington, D.C., 555 pp.
- Luco, N., Bachman, R. E., Crouse, C. B., Harris, J. R., Hooper, J. D., Kircher, C. A., Caldwell, P. J., and Rukstales, K. S. (2015). Updates to Building-Code Maps for the 2015 NEHRP Recommended Seismic Provisions, Earthquake Spectra, vol. 31, no. s1, pp. S245-S271, http://dx.doi.org/10.1193/042015EQS058M .
- Petersen, M.D., M. P. Moschetti, P. M. Powers, C. S. Mueller, K. M. Haller, A. D. Frankel, Y. Zeng, S. Rezaeian, S. C. Harmsen, O. S. Boyd, N. Field, R. Chen, K. S. Rukstales, N. Luco, R. L. Wheeler, R. A. Williams, and A. H. Olsen (2014). Documentation for the 2014 update of the United States national seismic hazard maps: U.S. Geological Survey Open-File Report 2014–1091, 243 p., http://dx.doi.org/10.3133/ofr20141091 .