Deep-Borehole Techniques for Continuous Monitoring of Crustal Activity and In-Situ Stress Measurement in Japan

Abstract

Deep borehole measurements have been carried out in two fields in Japan; the geothermal energy extraction project in the Tohoku (Sengan) geothermal area, and the earthquake prediction research in the Kanto-Tokai area (as “an area of specific observation” (e.g., Mogi 1981) for prediction of the next hazardous earthquake). I introduce deep borehole observatories for continuous observation of microearthquakes and ground tilt, and in-situ stress measurements in the Kanto-Tokai area.