SOURCE PARAMETERS OF THE APRIL, 16, 2013, SARAVAN IRAN GREAT EARTHQUAKE USING SPECTRA OF PAND SWAVES

On 16th April 2013 at 10:44 AM UTC, a great earthquake struck the Saravan region in South eastern Iran. The Mw was assessed to be 7.8 and a depth of 63km was assigned by IIEES. According to the deep depth of this event, this event can be associated with subduction of oceanic lithosphere of Arabian plate beneath the Makran ranges. Saravan earthquake was recorded at stations of Iranian National Broad-Band Seismic Network (INSN). In this study we determined source parameters of Saravan earthquake include seismic moment, corner frequency, source radius and stress drop using displacement spectra of P and S waves observed at 16 stations of INSN. The spectra of the records were corrected for attenuation then source parameters retrieved by fitting a Brune’s point source model. The average stress drops obtained here for P and S waves are 131 and 149 bars respectively. The larger average values of stress drop estimated for Saravan earthquake in comparison with median stress drop values obtained from previous studies for other regions of Iran can be related to different tectonic setting of the region.

Keywords:

Source Parameters , Saravan Earthquake , Spectrum , Stress Drop , Seismic Moment