BROAD-BAND ANALYSIS OF THE 21 SEPTEMBER, 1993 KLAMATH-FALLS EARTHQUAKE SEQUENCE

The source characteristics of the Klamath Falls earthquake sequence we re estimated from broadband seismograms recorded by the Berkeley Digit al Seismic Network (BDSN), TERRAscope, and western United States IRIS stations. Solutions were obtained for events ranging in size from M(om ega)3.8 to M(omega)6.0. An empirical Green's function inverse approach was used to estimate kinematic source parameters of the two M(omega)6 .0 mainshocks. Both events were found to have ruptured northwest on ad jacent segments of the Lake of the Woods system of normal faults. The two mainshocks abut where there is a pronounced 10 degrees to 20 degre es clockwise rotation of strike which may have initially acted as a ba rrier to a through-going M(omega)6.2 event.