U.S.-Japan Joint Seminar: The Relation Between Foreshocks and the Initiation of Large Earthquakes

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

9910066 Vidale This award supports the participation of American scientists in a U.S.-Japan seminar on the Relation Between Foreshocks and the Initiation of large Earthquakes, to be held in Kyoto, Japan from October 1-2, 2000. The co-organizers are Professors John Vidale at the University of California, Los Angeles and Professor James Mori at Kyoto University in Japan. The purpose of the seminar is to investigate the relationship between foreshocks and their subsequent mainshock, with special focus on how foreshocks can (or cannot) be used for earthquake prediction. Recently, research on the observed statistics of foreshocks has advanced in both the U.S. and Japan. Also, there have been improved observations of the details of the initiation process of earthquake ruptures on high-quality seismic instruments in both countries. Finally, theoretical studies on the nucleation and growth of ruptures are being actively pursued. The seminar will consist of two parts. The first purpose is to integrate and organize observation of foreshock occurrence. With consistent data compilation, they will compare spatial and temporal distributions of foreshocks and relate them to the ruptures of the subsequent large events. The second purpose is to explore what can be learned about the physical processes at the beginning of earthquakes, using the foreshock observations and related theoretical models of rupture initiation. The goal is to develop a better understanding of the mechanisms of rupture initiation, and a strategy to evaluate the feasibility of earthquake prediction. Seminar organizers have made a special effort to involve younger researchers as both participants and observers. The exchange of ideas and data with Japanese experts in this field will enable U.S. participants to advance their own work, and will set the stage for future collaborative projects. Dissemination of information from the meeting will be pu