Seismic-Hazard Maps for Alaska and the Aleutian Islands: 3HZ050

Probabilistic seismic hazard maps were prepared for Alaska portrayingpeak horizontal ground acceleration and horizontal spectral responseacceleration for 0.2, 0.3, and 1.0 second periods with probabilitiesof exceedance of 10% in 50 years and 2% in 50 years. This particulardata set is for horizontal spectral response acceleration for 0.3 secondperiod with a 10% probability of exceedance in 50 years. All ofthe maps were prepared by combining hazard derived from spatially-smoothed historic seismicity with hazard from fault-specific sources.The acceleration values contoured are the random horizontal component.The reference site condition is firm rock, defined as having an averageshear-wave velocity of 760 m/sec in the top 30 meters corresponding tothe boundary between NEHRP site classes B and C.
This data set represents the results of calculations of hazard curvesfor a grid of points with a spacing of 0.1 degrees in latitude andlongitude. The grid of points were contoured to produce the finalrepresentation of the seismic-hazard.