Mass estimates of scalar seismic moments of slight earthquake foci on the south of Sakhalin Island
Frequency dependence of the function of seismic waves damping for the southern part of Sakhalin Island has been determined for the first time based on the coda of seismic waves from the near earthquakes using the model of single scattering. The algorithm of automated definition of scalar seismic moments of slight earthquake foci has been realized. Mass estimates of seismic moments have been obtained as exemplified by the aftershocks of the Aug.17, 2006 Gornozavodsk earthquake (<i>M</i>W 5.6) and Kostromskoye earthquake swarm events of May- June 2004, which took place on South Sakhalin. The dynamic parameters of the foci have been determined based on the <i>SH</i>-wave spectra adjusted for absorption and geometrical discrepancy. The loglinear relation linking the seismic moment to the local magnitude has been established, which is in good agreement with the estimates obtained in other regions, and in a certain sense does not contradict the world average dependence.