TY - JOUR ID - 13083 TI - - JO - Journal of the Earth and Space Physics JA - JESPHYS LA - en SN - 2538-371X Y1 - 1998 PY - 1998 VL - 24 IS - 1 SP - EP - KW - Auto regressive KW - Modelling KW - Moving Average KW - prediction KW - seismicity KW - simulation DO - N2 - The released energies from the earthquakes occured during April 1967-February 1969 around Sefid-Rud dam with 4Okm radius were analysed as a time series for modeling. The magnitudes of the earthquakes are less than 4 in Richter scale, so thc time series is sufficient for the return period. The monthly release of energy was obtained from the average of total energy release per month and the model of Auto Regressive Moving Average (ARMA) is fitted to it. The model parameters are determined from mathematical relations and based on the correlation of the residuals, Port Monto and Akaike tests, the best model is recognized. This model is found to be the first order, which applies less parameters, simple and is showing seismicity of the region. Based on this model for the next 23 months the energy release and magnitude of the earthquakes are simulated. Since the biggest earthquake occured in this period has a magnitude 4, the simulation is restricted to a maximum magnitude 4. The simulation of the earthquakes shows that in August and October 1969 and in January 1971, an earthquake with magnitude of 3.5 to 4 would occur. It is obvious, if we have longer series and bigger earthquakes, we would be able to simulate bigger earthquakes. This simulation can compensate the lack of the earthquake records, due to equipment defect. For future seismicity of the region, the model is able to predict the seismicity of a month having the related data for the previous 21 months. By applying the data of 22 months we can predict the seismicity of the 23rd month which can be compared with the original data of 22nd and 23rd months. Finally by using 23 months original data, the prediction for the 24th month is applicable. So by these three month prediction in this region the trend of seismicity in the near future can be evaluated. The trend in this case is constant. UR - https://jesphys.ut.ac.ir/article_13083.html L1 - https://jesphys.ut.ac.ir/article_13083_25b4bd2dd3b33b95d153c742fa2133aa.pdf ER -