The tsunamis were not reported at all at Anchorage. The reason is 

 probatly that the waves were strongly attenuated by refraction effects 

 and by friction as they travelled up Cook Inlet. They would also have 

 encountered very strong currents from the ebbing astronomical tide which 

 would have dissipated their advance. It is unfortunate that no data 

 exist to shed light on the subject other than a report by Brown (196^+) 

 that at Kenai , ice shifted position three times in U5 minutes at about 

 11:00 p.m., March 27, along the edge of the basin. It is not known 

 whether any oil companies working in Cook Inlet possess marigrams that 

 show the tide state during and after the earthquake. 



There was, nevertheless, evidence of wave activity in the Turnagain 

 Arm shortly after the earthquake (Chance, I968). The quake occurred about 

 an hour before predicted high tide for Hope, located about midway along 

 the Turnagain Arm (Figures 1 and 33). Shortly after the quake, the water 

 swept in from the north as a UO-foot tide. The water ran 200 yards inland 

 flooding homes and other property. It is believed that this water move- 

 ment was due to the readjustment of the water level as a result of the 

 tilt which the Turnagain Arm received from the land subsidence (Figure 8). 

 It is also possible that the opposite horizontal thrusting of the land 

 at each end of the Turnagain Arm (Figure 16) induced an antinodal water 

 effect near the center where Hope is located. 



6. The Tsunami in Resurrection Bay, Kenai Peninsula 



The tsunami as it probably formed on the Continental Shelf off 

 Resurrection Bay (Figure 33) has been indicated in Figure 36a, which is re- 

 produced for convenience in Figure 133 5 with the inclusion of Resurrection 

 Bay, as if it were continuous with the section line BB' of Figure 33. 

 According to Figure 8, Resurrection Bay, during the earthquake, dropped 

 through a vertical distance of about 1 1/2 feet at the mouth to 6 feet 

 at the head. The horizontal displacement in the direction of the bay's 

 length, according to Figure 16, varied from about U5 feet at the head 

 to 55 feet at the mouth. The expectation from this is that the sudden 

 movement of the earth forming the boundaries of the bay, along with the 

 upthrust over the Continental Shelf, would have resulted in an immediate 

 relative upwelling of water of about 3 feet at the head of the bay, as 

 shown in Figure 133. This estimate is an intelligent guess and makes 

 no allowance for local or special effects. 



Before proceeding to a more detailed interpretation of the wave 

 effects actually observed in Resurrection Bay, we show the bathymetry 

 of the region in Figure 13^. Seward is situated on the west side of the 

 bay on an alluvial fan. The length of the bay to its mouth is about 23 

 nautical miles and the depth varies along the length between about 650 

 feet at the center near Caines Head to over 950 feet near its mouth and 

 in the northern half. The width of the bay is roughly uniform along a 

 large portion of its length, if the series of islands in the southern 

 half are regarded as a nominal boundary on the east side. The width is 

 about 2 1/2 nautical miles in the northern part of the bay. The con- 

 striction formed by Caines Head and the sill of the bed at this location 



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