Source Parameters of the Mw 6.6 Fandoqa (SE Iran) Earthquake of March 14, 1998

Document Type : Seismology and Engineering Seismology




In this study, the teleseismic body waveform modeling ofthe far-field P- and SH-waveforms as well as spectral analysis ofP-waves are used to determine the source parameters of March 14, 1998Fandoqa earthquake (Ms 6.9). Its epicenter is located southeast of Iranat Kerman province on the Gowk fault system. Previous focalmechanism solutions indicate motion on right-lateral strike slip faults.Based on waveform modeling, the results of this study represent aright-lateral strike slip motion on a NW-SE striking fault withparameters: Fault plane (strike=158°, dip=54° and the rake of 200°)and auxiliary plane (strike=58°, dip=76°, rake=-35°), depth of 4kmand seismic moment of 1.32E+19N.m. The spectral analysis of thefar-field P-wave pulses resulted in a fault length L ~ 20-26km, stressdrop Δσ~ 23 bars and average displacement ū~ 1m. In this study, thevariant models are also examined to determine the source dimensionand it is found that both the Madariaga and Sato-Hirasawa modelsare more consistent with the surface faulting in this area.