عنوان مقاله [English]
نویسندگان [English]چکیده [English]
One of the methods to study the earthquakes by using the recorded accelerations is to simulate the strong ground motion. The stochastic finite fault approach will aid in the development of ground-motion relations in data-poor regions. In this research, we identified the source parameters of the 20 December 2010 Rigan Earthquake using a ground-motion simulation based on a stochastic finite-fault model. The main shock of the 20 December 2010 Rigan Earthquake with magnitude MW = 6.7 (USGS), was recorded by 23 digital SSA-2 accelerograms. These stations were installed at epicentral distances ranging from 41 to 263 km. We estimated the causative rupture length and the downdip causative rupture width using the empirical relation from the best defined aftershock zone and the depth distribution of these aftershocks at 25.59 and 11.19 km, respectively. The fault plane was divided into 8×8 elements; it is based on the concept of self-similarity and revised scaling relations .The above method needs information related to attenuation, site characterization and frequency-dependent amplification as input, which are determined based on strong motion records, obtained during the main shock of 20 December 2010 Rigan Earthquake. In addition, the spectral decay parameter and the quality factor have been taken into account as other basic inputs for the mentioned method. The simulated results were compared with recorded ones on both frequency and time domains. The estimated strike and dip of the causative fault were 37 and 87, respectively. The rupture was propagated at (i,j) = (4,5) element, from Northeast to Southwest. The supposed stress drop was 60 bars. A quite satisfactory agreement was found between the simulated amplitude Fourier spectra and the recorded data at frequencies of engineering interest (0.5 to 20 Hz).
فروتن، م.، بلورچى، م. ج.، سلیمانى آزاد، ش.، اویسى، ب.، نعمتى، م.، شکرى، م. ع. و اسکندرى، م.، 1389، گزارش مقدماتى زمینلرزه 29 آذر 1389 کنارک (ریگان، کرمان)، سازمان زمین شناسى و اکتشافات معدنى کشور.
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