Earthquake prediction research in Japan

The first 5-year earthquake prediction project in Japan started in 1965. Now, the sixth 5-year project (1989-1993) is in progress. Various kinds of fundamental observations have been continued and the density of the observation network has increased with time, but there have been no successful cases of earthquake prediction. However, reliable data useful for long-term and short-term prediction are being steadily accumulated, and several cases have suggested the feasibility of earthquake prediction. In the Tokai district of central Honshu, where a major earthquake is expected to occur in the near future, a program for constant monitoring and assessment was formally inaugurated with the goal of forecasting an M 8 class earthquake. The results of research on recent major earthquakes in Japan are reviewed as well as the Tokai earthquake problem.