5 Synthesis of earthquake science information and its public transfer: A history of the Southern California earthquake center

Abstract

Earthquake science has made significant stride because of the plate tectonic revolution, wide acceptance of the fault model, and advances in computer technology. The increasing societal need for mitigating earthquake hazard has also been an important factor for its development. This chapter describes the concept of a master model, which is proposed as a framework for unifying multidisciplinary observations pertinent to earthquakes in Southern California. It also explores the concept of a master model serving as the dual purpose at the Southern California Earthquake Center (SCEC). The first-generation master model was constructed in response to the public's need for information on future earthquakes in Southern California after the Landers earthquake of 1992. This model gave a consensus view of the scientific community on future earthquakes in Southern California and also stimulated creative science through vigorous interactions among various disciplines involved in earthquake studies. The first-generation master model unifies the multidisciplinary data through its end product—namely, the Probabilistic Seismic Hazard Analysis (PSHA). The discovery of seismic guided waves trapped in the fault zone of the Landers earthquake of 1992 and the temporal change in their properties associated with possible healing of the fault measured in repeated controlled experiments can offer a field estimation of the parameters of the rate- and state-dependent friction law, which can be used to develop a computer model of earthquake occurrence relevant to the time scale of interest to SCEC.