7. The Importance of Postearthquake Investigations

Data and technical knowledge gained from postearthquake investigations of a dozen earthquakes since the 1964 Prince William Sound, Alaska, earthquake have significantly advanced the state‐of‐knowledge about earthquakes. These advances have motivated new and (or) improved programs, applications, and changes in public policy, including (1) the 1977 National Earthquake Hazards Reduction Program and its extensions, (2) earthquake prediction research, (3) deterministic and probabilistic hazards assessments, (4) design criteria for critical facilities, (5) earthquake‐resistant design provisions of building codes, (6) seismic safety elements, (7) seismic microzoning, (8) lifeline engineering, and (9) seismic safety organizations. To date, the 1971 San Fernando, California, earthquake has triggered more rapid advances in knowledge and applications than any other earthquake.