Computation shows that the area of the Inner Anchorage (Figiore 88) 

 "between the southwest end of Gull Island and Kodiak City is ahout 0.5 

 nautical square mile and that the volume of water to be drained in about 

 35 minutes would have been roughly 3.6 x 10° cubic feet. Available 

 outlets were the southwest entrance to the Inner Anchorage and the Near 

 Island channel. The latter has such small capacity that most of the 

 drainage would have had to take place via the Gull Island entrance. For 

 a cross-sectional area of this entrance of 1.2 x 105 square feet, taken 

 on average over the drop of water level, the average velocity of outflow 

 is calculated to be about 9 feet per second. The maximum velocity, 

 according to a sinusoidal rate of level drop, would be about 9'^ or 28 

 feet per second (l9 miles per hour). With some margin for error, this 

 estimate is in reasonably good accord with Jones' estimate of water 

 speed of 20-25 miles per hour (Figure 90). 



This outflow of impounded water apparently sucked out part of the 

 southwest breakwater of the boat harbor, and tore loose the Donnally 

 Atchison store and an aircraft hangar on the Near Island channel. But 

 the real damage came with the next two waves. 



Figure 90 shows that the next (third) wave was composite of the 

 first progressive wave crest of the tsunami, overlaid by the second wave 

 of the shelf oscillation and additional local oscillations (Figure 9Tc 

 and d). This monstrous wave, 35 to ilO feet high over a vast wave length, 

 moved into the area via the fastest route, up the Woody Island channel 

 (Figure 88) into the Near Island channel, already almost completely 

 denuded of water. This was the wave upon which the crab boat Rosemary 

 s\irf-rode up the channel. At its immediate front it had some of the 

 features of a foaming bore, but as Valley and Coles imply, it was mainly 

 a sloping front in the body of the wave crest. Such a wave configuration 

 would conform to the siorge waves studied experimentally by Cross (1966) 

 and illustrated in Figure 99- 



In Appendix D we give some discussion of water particle motions and 

 induced forces in tsunamis of surge type. The formula for the surge 

 velocity Ug 



Ug = 2 ./gdg (42) 



is reasonably supported by theory and experiment, and may be considered 

 to apply when the depth of water in front of the surge is small compared 

 to the total depth dg of the surge. Adopting dg ~ 37 feet, Ug is cal- 

 culated to be 69 feet per second or kT miles per hour. The Fremlins 

 had estimated the water speed in the Near Island channel as 50 miles 

 per hour (Chance, 1968). 



This wave came roaring up the channel from the northeast. It washed 

 away the channel docks and canneries, like the Alaska Packers Association 

 cannery shown in Figure 100. Figure 101 shows that only a few of the 

 supporting piles for this cannery remained (Tudor, I96U). An old stone 

 wall (Figure 101a), built by Russian settlers before the year I8OO, 

 survived the tsunami. Inspection of this structure by the authors 



Text resumes on page 159 

 156 



