桜島火山の爆発地震について

Abstract

The hypocenters of the explosion earthquakes of Sakurajima volcano are determined by usingthe data obtained by telemetering and precise recording system.Examining the distribution of the hypocenters, the following results are obtained.1) The majority of the epicenters of the explosion earthquakes are located within the activecrater rim.2) The depth of foci of the explosion earthquakes are located from sea level to 2 km under the sealevel. There exists no relation at present case between the focal depth of the explosion earthquakeand the magnitude of the earthquake or air shock wave, and also the stage of the volcanic activity.