山崎断層における伸縮変化の連続観測結果

Abstract

Continuous observation by 12 components of extensometers at the Yamasaki fault have pro-duced some significant results concerning the nature of active fault. Long period movement ofthe fault calculated from strain variations shows the left-lateral slip motion of the fault. Shortperiod strain variations have been observed larger by the components crossing the fractured zonethan by the components in the bed rock outside the fractured zone.It is important that a few days after short period movements by heavy rainfall seismic activityalong the fault increases.