Regional tsunami hazard assessment for False Pass and Perryville, Alaska

We assess potential tsunami hazard for the coastal communities of False Pass on Unimak Island and Perryville on the Alaska Peninsula. The primary tsunami hazard for these communities is considered to be near-field, with the major threat originating from tsunamigenic earthquakes along the Alaska-Aleutian megathrust. We numerically model tsunamis generated by three different megathrust earthquakes, analyze tsunami wave dynamics, and develop approximate tsunami hazard maps for the communities. The hypothetical tsunami scenarios examined simulate Mw9.0 megathrust earthquakes with a slip distribution in the 5-54 km (3-33 mi) depth range along the Alaska-Aleutian megathrust. The maximum runup heights are 13 m (42 ft) in False Pass and 21 m (69 ft) in Perryville. Results presented here are intended to provide guidance to local emergency management agencies in initial tsunami inundation assessment, evacuation planning, and public education for mitigation of future tsunami hazards. The complete report and digital data are available from the DGGS website: http://doi.org/10.14509/30192.