Science Center Objects

Probabilistic seismic hazard maps have been prepared for Alaska portraying ground motion values (peak ground acceleration and spectral amplitude at periods of 0.2, 0.3 and 1.0 seconds) at probabilities of exceedance of 2% and 10% in 50 years. Preparation of these maps followed the same general strategy as that followed for the U.S.G.S. seismic hazard maps of the contiguous United States, combining hazard derived from spatially-smoothed historic seismicity with hazard from fault-specific sources.

2007

Gridded seismic hazard curve data, gridded ground motion data, and mapped gridded ground motion values are available for the 2007 Alaska Seismic Hazard Model. Time-independent probabilistic seismic hazard data and maps of Alaska and the Aleutians 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. Development of the 2007 Alaska Seismic Hazard Model is documented in the USGS Open-File Report 2007-1043 (https://pubs.usgs.gov/of/2007/1043/).

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 (2007) 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.

1999

Gridded ground motion data and mapped gridded ground motion values are available for the 1999 Alaska Seismic Hazard Model. Probabilistic seismic hazard data and maps of Alaska and the Aleutians for peak ground acceleration (PGA) and 0.2, 0.3, and 1.0 second spectral acceleration at probability levels of 2 percent in 50 years (annual probability of 0.000404) and 10 percent in 50 years (annual probably of 0.0021), assuming firm rock soil conditions at 760 m/s, are available. Development of the 1999 Alaska Seismic Hazard Model is documented in the USGS Open-File Report 99-36 (https://doi.org/10.3133/ofr9936).

This dataset is considered a legacy dataset. The original dataset was released at the time of publication of the seismic hazard model (1999) 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.