Crustal Deformation in Southcentral Alaska: The 1964 Prince William Sound Earthquake Subduction Zone

摘要

The M(sub w)= 9.2 Prince William Sound (PWS) that struck south central Alaska on March 28, 1964, is one of the important earthquakes in history. The importance of this Great Alaska Earthquake lies more in its scientific than societal impact. While the human losses in the PWS earthquake were certainly tragic, the sociological impact of the earthquake was less than that of earthquakes that have struck heavily populated locales. By contrast Earth science, particularly tectonophysics, seismology, and geodesy, has benefited enormously from studies of this massive earthquake. The early 1960s was a particularly important time for both seismology and tectonophysics. Seismic instrumentation and analysis techniques were undergoing considerable modernization. For example, the VELA UNIFORM program for nuclear test detection resulted in the deployment of the World Wide Standard Seismographic Network in the late 1950s and early 1960s. Correspondingly, considerable effort was being devoted by the scientific community to understanding seismic source properties, the characteristics of seismic signals, and the interior structure of the Earth. The study of the PWS earthquake benefited from this attention to global as well as local seismological issues and, reciprocally, the study of the PWS earthquake contributed much to the research efforts of the time. In the early 1960's the paradigm of plate tectonics was in its infancy. Many fundamental plate tectonics investigations, such as the study of marine magnetic anomalies by Vine and Mathews (1963), were just beginning to be reported in the scientific literature.