Analysis of the March 13, 2005 Earthquake in Southeastern Iran Based on Teleseismic and Regional Distances

Document Type : Seismology and Engineering Seismology




The treatment of the seismic source inverse problem, when waveform data are available, is simple and elegant using synthetic seismogram formalism. This study constrains source parameters of the March 13, 2005 earthquake by analyzing body wave seismograms in teleseismic and regional distances. The results from waveform modeling indicate that source depth was 32km and that it was a normal mechanism with a small strike slip component. The duration of source time function (STF) is approximately 5sec. Regional determination of body wave (S) spectra are used to estimate the parameters of seismic moment (Mo=10.45×1025dyne-cm), corner frequency (fo=0.54hz), source dimension (R=2.5km) and stress drop ( Δσ= 0.26×104 bar). Comparison between obtained results and the Harvard CMT solution data show that there is some difference in common parameters, especially in the depth value and seismic moment (the depth value and seismic moment reported by Harvard is 56km and 1.17× 1025dyne-cm respectively). Scatter in the seismic moment values is caused by such factors as the site conditions and errors in the radiation pattern corrections.