Fairbanks by releveling the previously surveyed first order level lines 

 tied to tidal bench marks at Seward, Anchorage, and Valdez (Plafker, 1965; 

 Small, 1966). This work was done by the U. S. Coast and Geodetic Survey. 

 The result of an initial survey of a U. S. Geological Survey team is illus- 

 trated in Figure 9 and shows that Montague Island, at the mouth of Prince 

 William Sound, experienced the greatest uplift on land (about 33 feet). 

 The interpretation of Figiire 9 (from Plafker and Mayo, 1965; Plafker, I965I 

 differs only in minor detail from that of the U. S. Coast and Geodetic 

 Survey (1966), Figure 10, which relied heavily on the original isobase 

 contouring and measiirements provided by Plafker (see also Plafker, I967). 



The only visible faulting that occurred anywhere during the earth- 

 quake, other than local fissures and grabens, was on Montague Island, 

 Figure 11. Here vertical displacements of 12 to 17 feet mark the 

 Manning Bay and Patton Bay faults (see inset cross-sections. Figure 11 ). 



Although the U. S. Coast and Geodetic Survey has been engaged on a 

 massive program of resurveying the marine areas affected by the earthquake 

 (cf. U. S. Coast and Geodetic Survey, 1965; Wood, et al, I966), the only 

 positive results available to us at this time (apart from niimerous chart- 

 lets that have been issued as revisions to U. S. Coast and Geodetic Survey 

 hydrographic charts) are those reported by Malloy (I96U , I965, I966) and 

 by Malloy and Merrill (1967) mainly for the area southwest of Montague 

 Island. The essence of these is shown in Figure -10 and in greater detail 

 in Figure 12 which shows that several localized areas have sustained up- 

 lifts in excess of 50 feet. Comparison here is made between hydrographic 

 data collected in 1927 and fathograms recorded in 196^+. The equipment 

 used in 1927 for making the soundings was a submarine sonic fathometer 

 which had been adequately checked against lead-line soundings. The data 

 are therefore unusually good. Also, this area is free from sediments, 

 which indicates that the measured differences are not affected by scour- 

 ing or sedimentation. Figui-e 13 shows typical vertical cross-sections 

 along the lines A, B, C, ... H, I (Figure 12); all exhibit a remarkable 

 consistency of general profile, which alone suggests reliable data. 



The hinge line of zero movement was established from known movements 

 along the coastline (see Figure 8). The hinge line runs from Sitkinak 

 Island along the southeast coast of Kodiak Island to the mouth of 

 Resurrection Bay and further on toward the epicenter, thence bending 

 eastward toward Valdez. The general nature of land-level change is 

 illustrated in Figure ik (Plafker, I965 ) . Here the individual profiles 

 AA' , BE' and CC should be referenced to their locations in Figure 8. 

 Maximum subsidence of the land is seen to be about 7 feet on the Kenai 

 Peninsula. It is not known whether uplift in the deeper water over the 

 shelf between Montague Island and Kodiak Island has occurred of a mag- 

 nitude comparable with, or greater than, the 50 feet measured in the 

 proximity of Montague Island (cf. Malloy, 1966), but when the evidence 

 for tsunami generation is considered, the inference must be that there 

 probably has been uplift of comparable magnitude. 



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