Deaggregation of probabilistic ground motions in the central and eastern United States

S. Harmsen; D. Perkins; A. Frankel

doi:10.1785/bssa0890010001

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Deaggregation of probabilistic ground motions in the central and eastern United States

S. Harmsen·D. Perkins·A. Frankel

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Abstract

Probabilistic seismic hazard analysis (PSHA) is a technique for estimating the annual rate of exceedance of a specified ground motion at a site due to known and suspected earthquake sources. The relative contributions of the various sources to the total seismic hazard are determined as a function of their occurrence rates and their ground-motion potential. The separation of the exceedance contributions into bins whose base dimensions are magnitude and distance is called deaggregation . We have deaggregated the hazard analyses for the new USGS national probabilistic ground-motion hazard maps (Frankel et al. , 1996). For points on a 0.2° grid in the central and eastern United States (CEUS) , we show color maps of the geographical variation of mean and modal magnitudes ( M , Mˇ ) and distances ( D , Dˇ ) for ground motions having a 2% chance of exceedance in 50 years. These maps are displayed for peak horizontal acceleration and for spectral response accelerations of 0.2, 0.3, and 1.0 sec. We tabulate M , D , Mˇ , and Dˇ for 49 CEUS cities for 0.2- and 1.0-sec response. Thus, these maps and tables are PSHA-derived estimates of the potential earthquakes that dominate seismic hazard at short and intermediate periods in the CEUS.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 24.81584356675542° to 50.267706320710346° latitude; -98.35529324972059° to -66.01154324972084° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

S. Harmsen, D. Perkins, A. Frankel. 1999. Deaggregation of probabilistic ground motions in the central and eastern United States. https://doi.org/10.1785/bssa0890010001

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