地震目录的完整性对CBS(Cumulative Benioff Strain)值计算结果影响较大,直接影响对特定地震区强震发生时间窗口的判断.对某些地震区数据分析时若考虑最小完整性震级Mc,则可大大降低预测临界CBS值和实际值之间的误差.为此,本文考虑Mc,对新疆及其邻区某些地震区未来震情进行重新研判,结果表明:Mc对拜城与库尔勒地震区的临界值和监测值影响不大,而对中吉边境、新源-阿拉木图、昆仑山口西和若羌地震区的临界值和监测值则有较大影响.目前拜城、库尔勒和若羌三个地震区均距临界状态较远,故预测发震时间窗口为中长期.中吉边境地震区和新源-阿拉木图地震区未来分别将有大震和巨震发生,按近期地震活动性判断,预测发震时间窗口为中长期.昆仑山口西地震区未来将发生强震,目前已接近临界状态,预测发震时间窗口为中短期.本文研究结果可供有关部门参考.
The integrity of earthquake catalogue has a significant influence on calculation of the critical CBS(Cumulative Benioff Strain)value,which further directly influences the judgment of the predictive time window of strong earthquake occurrence for a specific seismic zone.It was noted that when considering the minimum magnitude of completeness(Mc),the error between the critical values and actual monitored ones of CBS could be greatly reduced for some seismic zones.In view of this,the present study reanalyzed the earthquake situation for some seismic zones in the Xinjiang region and its adjacent regions.The results indicate that whether considering Mcor not,it has no obvious impact on the prediction results of the Baicheng and Kuerle seismic zones.On the contrary,Mchas a significant influence on the prediction results of the China-Kyrgyzstan border seismic zone,XinyuanAlmaty seismic zone, Kunlunshankouxi seismic zone and Ruoqiang seismic zone.Considering that it is far away from the critical state,all of the predictive time windows for the Baicheng,Kuerle and Ruoqiang seismic zones are in the scale of the medium-long term.Meanwhile,it was found that a major earthquake and a great earthquake would occur in the ChinaKyrgyzstan border seismic zone and Xinyuan-Almaty seismic zone,respectively.The predictive time windows for these two zones are also in the scale of medium-long term according to the recent seismicity.Moreover,an impending strong earthquake will occur in the Kunlunshankouxi seismic zone with a scale of medium-short term. The analysis results above could be considered by the related department.