ILLUSTRATIONS 

 Figiire Page 



19 Theoretical models of vertical movements associated with 

 Alaskan Earthquake on a section normal to belt of epicenters . 26 



20 Equal-area projection of the focal mechanism solution based 



on first motion of P waves 29 



21 Mechanism diagrams (st'ereographic projection of earthquakes) 



in Prince William Sound Region and Kodiak Island Region ... 29 



22 Tectonic displacements of the free surface 31 



23 Relationship of major fault length to earthquake magnitude . . 33 



2i+ Microbarograph record from La Jolla showing atmospheric 



"tsunami" from Alaskan earthquake 3^ 



25 (a) Projection of imaginary wavefronts from observation 



stations back towards the tsunami source 35 



(b) Hypothetical model of the tsunami soiorce, showing 



negative and positive wave fronts 35 



26 (a) Inferred generating area of the Alaskan Tsunami 36 



(b) Apparent generating area of the Alaskan Tsunami 37 



27 Approximate locations of Tsunami Wave front at one-ho\ir 

 intervals (GMT) in the Pacific Ocean 38 



28 Relationship of diameter of tsunami source region to 

 Earthquake magnitude ^-^ 



29 Pictorial view of relative positions of earth, moon, and 

 sun on occasions of notable great earthquakes ..... 



k2 



30 Schematic diagram of the earth, moon, and sun relationship 



at the time of the Alaskan earthquake ^2 



31 Tide elevations with reference to mean sea level at the 



time of the Alaskan earthquake . ^^ 



32 Oscillations of water level in the Gulf of Mexico, related 



to the Alaskan earthquake ..... ^^ 



33 General Bathymetry of the Continental Shelf, Gulf of Alaska, 

 Prince William Sound and Cook Inlet ..... 53 



3^ Inferred mechanism of tsunami generation between Montague 



and Middleton Islands , Gulf of Alaska 5 



