ON THE SEQUENCE OF EARTHQUAKES

Abstract

In and near Kinki District, many microearthquakes of seismic magnitude from less than zero up to about 1 or 2 are occurring almost stationarily. But they are classified into several earthquake sequences according to the space distribution of their foci and the time series of their occurrence. With the help of the elastic rebound theory, the characteristics of these sequences of microearthquakes were investigated in relation to that of severe earthquakes of M 5 or more. As the result, it could be concluded that the seismic activity at a certain region was clearly characterized by the main shock and its beforeshock and aftershock sequences and also that the sequence structure of earthquake swarms might be adequately explained by the rheological models with the help of the experimental results on rock deformation and an application of the rate process theory to the rheological materials in the earth's interior.