The Alaskan-Aleutian arc has a history of rupturing in large and great earthquakes. The most recent sequence began in 1938 and has ruptured almost the entire arc from southern Alaska to the western Aleutians (Figure 1). This sequence includes five great earthquakes: the 1938 Alaskan, 1946 Aleutian, 1957 (Central) Aleutian, 1964 Prince William Sound (or Alaskan), and 1965 Rat Islands earthquakes. Three of these five-the 1957, 1964, and 1965 earthquakes-are among the 10 largest earthquakes of the 20th century. These earthquakes are clearly important to those who assess seismic hazards. These five earthquakes caused hundreds of deaths and millions of dollars of damage, both from the earthquakes themselves and from.
