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1996 United States (Lower 48) Seismic Hazard Long-term Model Completed

By Earthquake Hazards Program December 19, 2019

Seismicity catalogs, gridded seismic hazard curve data, gridded ground motion data, and mapped gridded ground motion values are available for the 1996 National Seismic Hazard Model for the Conterminous U.S. Seismicity catalogs are available for the western U.S. (in Mw) and central and eastern U.S. (in mb).

Probabilistic seismic hazard data and maps of the conterminous U.S. for peak ground acceleration (PGA) and 0.1, 0.2, 0.3, 0.5, 1.0 and 2.0 second spectral acceleration at probability levels of 2 percent in 50 years (annual probability of 0.000404), 5 percent in 50 years (annual probability of 0.001026), and 10 percent in 50 years (annual probability of 0.0021), assuming firm rock soil conditions at 760 m/s, are available. Hazard was calculated on a 0.1 degree by 0.1 degree grid, defined by a bounding box encompassing the conterminous U.S. (-125 to -65 degrees longitude west, 24.6 to 50 degrees latitude north). Development of the 1996 National Seismic Hazard Model for the Conterminous U.S. is documented in the USGS Open-File Report 96-532.

This dataset is considered a legacy dataset. The original dataset was uploaded to the USGS website at the time of publication of the seismic hazard model (1996) but was later moved over the the USGS ScienceBase Catalog (2019). The original dataset was assumed to be complete and accurate, but may contain inconsistencies when compared to more recent, actively maintained datasets.

Below are publications associated with this project.

Figures from Open-File Report 96-532

National Seismic Hazard Maps: Documentation June 1996 (6MB ZIP file)

Site-response maps for the Los Angeles region based on earthquake ground motions

Ground-motion records from aftershocks of the 1994 Northridge earthquake and main-shock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response in the urban Los Angeles, California, area. Two frequency bands are considered, 0.5-1.5 Hz and 2.0-6.0 Hz. Instrument characteristics prevented going to lower frequenc
Authors
Stephen H. Hartzell, Stephen C. Harmsen, Arthur D. Frankel, David L. Carver, Edward Cranswick, Mark E. Meremonte, John A. Michael
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

Preparation of earthquake catalogs for the National Seismic-Hazard Maps: Contiguous 48 states

No abstract available.
Authors
Charles C. Mueller, Margaret G. Hopper, Arthur D. Frankel

First-generation site-response maps for the Los Angeles region based on earthquake ground motions

Ground-motion records from aftershocks of the 1994 Northridge earthquake and mainshock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response relative to a rock site for the urban Los Angeles area. Site response is estimated at 232 mainshock and 201 aftershock sites relative to a low-amplitude site in the San
Authors
S. Hartzell, S. Harmsen, A. Frankel, D. Carver, E. Cranswick, M. Meremonte, J. Michael

Hazard maps help save lives and property

Authors
William M. Brown, David M. Perkins, Edgar V. Leyendecker, Arthur D. Frankel, James W. Hendley, Peter H. Stauffer

National Seismic-Hazard Maps: Documentation June 1996

In this release of hazard maps we present numerous maps and data with varying parameters. The computations for these maps and data used 50 year return periods on firm rock at 760 m/sec. All of the maps were prepared by combining hazard derived from spatially- smoothed historic seismicity with hazard from fault-specific sources. For more information please read our full documentation. Although
Authors
Arthur D. Frankel, Charlies S. Mueller, Theodore P. Barnhard, David M. Perkins, E. V. Leyendecker, Nancy Dickman, Stanley L. Hanson, Margaret G. Hopper

Seismic-Hazard Maps for the Conterminous United States

Authors
Arthur D. Frankel, C. Mueller, T. Barnhard, D. Perkins, E. V. Leyendecker, N. Dickman, S. Hanson, M. Hopper

Seismic-Hazard Maps for California, Nevada, and Western Arizona/Utah

Authors
Arthur D. Frankel, C. Mueller, T. Barnhard, D. Perkins, E. V. Leyendecker, N. Dickman, S. Hanson, M. Hopper
  • Overview

    Seismicity catalogs, gridded seismic hazard curve data, gridded ground motion data, and mapped gridded ground motion values are available for the 1996 National Seismic Hazard Model for the Conterminous U.S. Seismicity catalogs are available for the western U.S. (in Mw) and central and eastern U.S. (in mb).

    Probabilistic seismic hazard data and maps of the conterminous U.S. for peak ground acceleration (PGA) and 0.1, 0.2, 0.3, 0.5, 1.0 and 2.0 second spectral acceleration at probability levels of 2 percent in 50 years (annual probability of 0.000404), 5 percent in 50 years (annual probability of 0.001026), and 10 percent in 50 years (annual probability of 0.0021), assuming firm rock soil conditions at 760 m/s, are available. Hazard was calculated on a 0.1 degree by 0.1 degree grid, defined by a bounding box encompassing the conterminous U.S. (-125 to -65 degrees longitude west, 24.6 to 50 degrees latitude north). Development of the 1996 National Seismic Hazard Model for the Conterminous U.S. is documented in the USGS Open-File Report 96-532.

    This dataset is considered a legacy dataset. The original dataset was uploaded to the USGS website at the time of publication of the seismic hazard model (1996) but was later moved over the the USGS ScienceBase Catalog (2019). The original dataset was assumed to be complete and accurate, but may contain inconsistencies when compared to more recent, actively maintained datasets.

  • Publications

    Below are publications associated with this project.

    Figures from Open-File Report 96-532

    National Seismic Hazard Maps: Documentation June 1996 (6MB ZIP file)

    Site-response maps for the Los Angeles region based on earthquake ground motions

    Ground-motion records from aftershocks of the 1994 Northridge earthquake and main-shock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response in the urban Los Angeles, California, area. Two frequency bands are considered, 0.5-1.5 Hz and 2.0-6.0 Hz. Instrument characteristics prevented going to lower frequenc
    Authors
    Stephen H. Hartzell, Stephen C. Harmsen, Arthur D. Frankel, David L. Carver, Edward Cranswick, Mark E. Meremonte, John A. Michael
    By
    Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

    Preparation of earthquake catalogs for the National Seismic-Hazard Maps: Contiguous 48 states

    No abstract available.
    Authors
    Charles C. Mueller, Margaret G. Hopper, Arthur D. Frankel

    First-generation site-response maps for the Los Angeles region based on earthquake ground motions

    Ground-motion records from aftershocks of the 1994 Northridge earthquake and mainshock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response relative to a rock site for the urban Los Angeles area. Site response is estimated at 232 mainshock and 201 aftershock sites relative to a low-amplitude site in the San
    Authors
    S. Hartzell, S. Harmsen, A. Frankel, D. Carver, E. Cranswick, M. Meremonte, J. Michael

    Hazard maps help save lives and property

    Authors
    William M. Brown, David M. Perkins, Edgar V. Leyendecker, Arthur D. Frankel, James W. Hendley, Peter H. Stauffer

    National Seismic-Hazard Maps: Documentation June 1996

    In this release of hazard maps we present numerous maps and data with varying parameters. The computations for these maps and data used 50 year return periods on firm rock at 760 m/sec. All of the maps were prepared by combining hazard derived from spatially- smoothed historic seismicity with hazard from fault-specific sources. For more information please read our full documentation. Although
    Authors
    Arthur D. Frankel, Charlies S. Mueller, Theodore P. Barnhard, David M. Perkins, E. V. Leyendecker, Nancy Dickman, Stanley L. Hanson, Margaret G. Hopper

    Seismic-Hazard Maps for the Conterminous United States

    Authors
    Arthur D. Frankel, C. Mueller, T. Barnhard, D. Perkins, E. V. Leyendecker, N. Dickman, S. Hanson, M. Hopper

    Seismic-Hazard Maps for California, Nevada, and Western Arizona/Utah

    Authors
    Arthur D. Frankel, C. Mueller, T. Barnhard, D. Perkins, E. V. Leyendecker, N. Dickman, S. Hanson, M. Hopper