Source parameters and crustal Q for four earthquakes in South Carolina

Two three-component seismometers (one surface and one borehole) were re-installed on the Savannah River Site (SRS), South Carolina in July 1992 to determine attenuation in the Coastal Plain sediment wedge and source parameters of local earthquakes. Four earthquakes M ~1.8 to 3.6 were recorded during the next 6 months. The largest event was located near Summerville within the meizoseismal area for the 1886 Charleston earthquake. Although source parameters have been determined from strong motion data and short-period regional networks for east coast earthquakes, these are some of the first source parameters determined from broad-band digital recorders. This paper determines source parameters such as moment, stress drop, and the attenuation parameter t* using a non-linear least-squares algorithm. -from Author