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We evaluate potential tsunami hazards for several communities in lower Cook Inlet, including Anchor Point, Kenai, Ninilchik, and Tyonek, by numerically modeling the extent of inundation from tsunami waves generated by hypothetical earthquakes. We define an updated suite of earthquakes—including Tohoku-style megathrust ruptures and other sources in the eastern part of the Alaska–Aleutian megathrust—to calculate vertical seafloor displacements and model resulting tsunami dynamics. A hypothetical earthquake spanning from Kodiak Island to Prince William Sound with maximum slip distributed between depths of 5 and 22 km (3.1 and 13.7 mi) results in “worst case” tsunami inundation for all communities. If the tsunami arrives at high tide, the maximum predicted overland flow depths in the communities can reach up to 10 m (32.8 ft), and the currents could be as strong as 12 m/sec (23.4 knots). Dangerous wave activity is expected to last for more than 24 hours. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami damage. [ABSTRACT FROM AUTHOR]

In this report, we evaluate potential tsunami hazards for southeastern Alaska communities of Elfin Cove, Gustavus, and Hoonah and numerically model the extent of inundation from tsunami waves generated by tectonic and landslide sources. We perform numerical modeling of historic tsunami events, such as the tsunami triggered by the 1964 Great Alaska Earthquake, and the tsunami waves generated by the recent 2011 Tohoku and 2012 Haida Gwaii earthquakes. Hypothetical tsunami scenarios include variations of the extended 1964 rupture, megathrust earthquakes in the Prince William Sound and Alaska Peninsula regions, and a Cascadia megathrust earthquake. Local underwater landslide events in Taylor Bay and Port Frederick, and a rockslide in Tidal Inlet are also considered as possible tsunamigenic scenarios. Numerical modeling results, combined with historical observations in the region, are intended to provide guidance to local emergency management in tsunami hazard assessment, evacuation planning, and public education for the reduction of future tsunami risk. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate potential tsunami hazards for the community of Sitka. We numerically model the extent of inundation from tsunami waves generated by near- and far-fi eld tectonic sources. We performed numerical modeling of historic events at Sitka, such as the tsunami triggered by the 1964 Great Alaska Earthquake, and the tsunami waves generated by the recent 2011 Tohoku and 2012 Haida Gwaii earthquakes. Hypothetical tsunami scenarios include variations of the extended 1964 rupture, megathrust earthquakes in the Alaska Peninsula region and in the Cascadia subduction zone, and a thrust earthquake in the region of the Queen Charlotte--Fairweather fault zone. Results of numerical modeling combined with historical observations in the region are intended to provide guidance to local emergency management in tsunami hazard assessment, evacuation planning, and public education for the reduction of future tsunami risk. [ABSTRACT FROM AUTHOR]