Introduction
The Great 1964 Alaska earthquake generated catastrophic tsunami waves that devastated many towns in the Prince William Sound area of Alaska, along the Gulf of Alaska, along the West Coast of Canada and the United States, and in the Hawaiian islands. In Alaska, the tsunami run-up measurements varied from 6.1 m at Kodiak Island, 9.1 m at Valdez, 24.2 m at Blackstone Bay, and 27.4 m at Chenega.

Loss of Lives and Damages
The Great 1964 Alaska earthquake and the tsunami waves resulting from it, took the lives of more than 122 people and caused over $106 million (1964 dollars) in total damage. A total of 119 people lost their lives in Alaska, Oregon and California as a result of tsunami waves generated in the Gulf of Alaska and the locally generated tsunami waves in Prince William Sound. Most of the damage and most of the lives lost in Alaska were due to large local tsunami waves within the Prince William Sound area, rather than to the earthquake itself. Of the 119 deaths attributable to tsunami waves, about one-third were due to the open-ocean tsunami generated in the Gulf of Alaska. Of these 4 occurred at Newport Beach, Oregon; 12 at Crescent City, California; and about 21 in Alaska. The rest of the deaths were caused by tsunami waves generated within Prince William Sound.
 

Two Areas of Tsunami Generation
Although most studies refer to the March 27, 1964 Great Earthquake in Alaska as having generated one single tsunami, in reality there were two different types of very distinguishable tsunami generation mechanisms associated with this earthquake: one along the continental shelf bordering the Gulf of Alaska; the other, in the Prince William Sound region.

The Open Ocean Tsunami: Tectonic movements of the sea floor were responsible for the generation of the open ocean tsunami along the continental shelf bordering the Gulf of Alaska. Destructive tsunami waves from this generating area were responsible for destruction on Kenai Peninsula, on Kodiak Island, on Trinity islands, on Vancouver Island, the West Coast of United States and the Hawaiian islands. Very little energy from this main tsunami entered the Prince William Sound area. Most of the energy from the open ocean tsunami generated in the Gulf, radiated in a southeast direction towards Canada, the Western United States, and the Hawaiian Islands.

The Prince William Sound Tsunami Waves: Tectonic movements and resulting landslides were responsible for most of the local tsunami waves which caused the destruction and deaths within the Prince William Sound region. Very little of the energy from these local tsunami waves escaped the Sound, thus contributing very little, if at all, to the overall tsunami energy of the open ocean tsunami along the Gulf of Alaska. Most of the tsunami energy from the local tsunami waves stayed within the Sound, reverberating and, in the case of Valdez Bay, setting up resonance effects and maximum inundation, hours after the earthquake.

 1964 Tsunami in the Gulf Of Alaska

Boundaries of Tsunami Generation Area: The boundaries of the generating area of the tsunami in the Gulf of Alaska extended from southern Kodiak Island (near Trinity Islands) northeast to Prince William Sound. Within the Gulf of Alaska, the zone of deformation to the east appeared to die out between the Bering Glacier and Cape Yakataga. The width of the generating area is estimated at 150 km, and includes the Gulf of Alaska coastal area as far east as the Bering Glacier, and the continental shelf and part of the slope. The northward limit of the tsunami generating area is restricted by the land boundaries, and the western limit extends to the west side of Shelikof Strait and Cook Inlet. The seaward limits of the open sea tsunami-generating area, determined by means of tsunami wave refraction show the seaward boundary to be near the 200-m depth contour which defines the edge of the continental shelf.

Total Energy of the Open Sea Tsunami: The energy associated with the open sea tsunami in the Gulf of Alaska was estimated to be in the order 6 x10 (raised to the 21st power) in ergs
(166666666.66 kilowatt-hours).

Energy Radiation: Tsunami energy radiation was preferentially directed towards the south east and this is why more damage was done to the North American coast than anywhere else east or south of the generating area. The preferential radiation of energy towards the southeast is attributed to the orientation of the tectonic displacements along the continental shelf of the Gulf of Alaska.

Kodiak Island: The shores of the Kodiak Island were struck by tsunami waves within 34 minutes after the earthquake. The only reliable tide gauge record from the generating area is the one obtained by personnel of the U. S. Navy Fleet Weather Station at Kodiak (see figure) This record has been for the 1.7 m ((5.6-foot)) submergence of the area as determined from tide gages of USC&GS (1964).
The third and fourth waves were the highest and most destructive at Uzinki, Kodiak City, Women's Bay and elsewhere on the island of Kodiak. The significance of this is that, if the tsunami waves that hit the island of Kodiak were the result of only crustal movements, then the first wave could be expected to be the highest, at least within the generating area, where indeed Kodiak island was located. However, since the third and fourth waves were the highest, a theory of generation from a single pattern of crustal deformation is not satisfactory. Thus we must conclude that the pattern of crustal deformations was indeed complex and factors such as as reflection from coastal boundaries, wave interaction, refraction, diffraction and resonance, contributed to subsequent waves being the highest.

           Kodiak island before tsunami                                           Kodiak island after tsunami

All information courtesy of Dr. George P.C.'s tsunami page