As at Seward and Valdez , the waterfront was destroyed mostly "by the 

 collapse of the foundations resulting from the submarine slides and the 

 regional subsidence of 5.3 feet. However, the wave damage was extensive 

 and involved the Union Oil tank farm, which was set on fire, and two 

 lumber company plants which were virtually demolished, as also the Alaska 

 Railroad docks, and numerous homes and small buildings. 



The sea waves are credited with having caused $10 million worth 

 of damage at Whittier, and took 13 lives out of a population of TO. 

 Undoubtedly the waves were relatively more severe than at Valdez and 

 Seward. 



At Cordova, in the Orca Inlet near the mouth of Prince William Sound, 

 the regional tectonic movement was 6 feet of uplift and about Uo feet of 

 horizontal thrust to the southeast. 



Sea approaches to Cordova are relatively shallow, and there is no 

 evidence of submarine slides having occurred in the region. The wave 

 pattern of the inferred marigram (Figure 202) thus has no large amplitude 

 waves of 3 to 5 minutes period such as characterized the situations at 

 Seward, Valdez, and Whittier. Initial waves following the earthquake 

 proved to be of little consequence, but shortly after midnight an ex- 

 ceptional wave rose above the preexisting highest tide level. This wave 

 buoyed the dock off its pilings, carried away several small houses and 

 buildings, and generally flooded the waterfront. 



Wave damage at Cordova was estimated at $2 million. General upheaval 

 of the harbor created problems of dredging new access routes through shoals 

 or of extending piers about 100 feet to reach water of suitable depth, 

 equivalent to prequake conditions. The tsunami had the notable effect of 

 producing both scouring and silting in different places of the Orca Inlet. 



6. Effects of the Main Tsunami along the North American Seaboard 



The tectonic movement in the Gulf of Alaska was such as to pre- 

 scribe direction of the main part of the energy of the tsunami toward the 

 North American coastline. Dajnage in excess of $10 million occurred along 

 the greatly indented coastline of Canada, mainly in the form of flooding, 

 buildings swept away, wharves damaged, and log booms and limiber mills 

 destroyed. No loss of life was reported in this area. 



The most serious damage in Canada occurred at Port Alberni . Here 

 the greatly amplified tsunami waves arrived on the high spring tide 

 (range about IT feet), but, by good fortune, the first wave (of lower 

 amplitude than the second) arrived slightly ahead of the tidal peak and 

 alerted the population to the danger. Houses, boats, logs, and other 

 moveable objects were swept away and destroyed; wharf structures were 

 buoyed and buckled. The damage at Port Alberni alone was estimated to 

 be $10 million. 



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