If this area of the North American continent is preloaded with the stress that can lead to earthquakes, it will be difficult to assess earthquake risk in the region.
如果北美大陆该地区预先就有诱发地震的应力，将很难评估该地区的地震风险。
Then the characteristics of seismic activities in the last 18 years and their tectonic setting are studied, and the future earthquake risk in this region is also discussed.
然后，分析研究了近18年来地震活动特征和地质构造背景； 探讨了本区未来地震危险性等问题。
Fifth, there appeared trend anomalies of seismometry results and other microscopic precursors, implying that middle-term risk of strong earthquake exists in the determined monitoring region.
五是测震和其它微观前兆趋势性异常出现，说明所圈定监视区的中期强震危险性存在。
At last, the flowchart of risk assessment of urban earthquake disaster is designed, and zonation arithmetic of risk region is showed.
最后设计了城市地震灾害风险评价流程，并给出了城市地震灾害风险区划算法。
At last, the flowchart of risk assessment of urban earthquake disaster is designed, and zonation arithmetic of risk region is showed.
最后设计了城市地震灾害风险评价流程，并给出了城市地震灾害风险区划算法。
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