摘要
1970年以来银川地区ML4级地震在时间上丛集发生,分别从主震震前小震与震后余震分布特征、余震序列参数计算和震源机制解的角度,研究了以上地震的活动特征。结果显示:每次地震的发生均具有一定的独立性;可计算余震参数的地震序列为非前兆震群,这一点与实际相符;震源机制解显示几次地震的发震断层主要属于银川隐伏断裂,并可能与该断裂附近的一系列次级断裂有关。分析认为几次地震的发生可能是局部应力调整的结果,与未来该区域是否发生大震关系不大,同时可以推测未来该区域依旧可能发生类似震级的有感地震。
The characteristic of ML4 earthquakes in Yinchuan region since 1970 is time clustering. The paper analyzes the activity characteristic of earthquakes from three aspects, that are distribution characteristic of small earthquakes before the main earthquake and aftershocks, parameters of aftershock sequence, and focal mechanism of the earthquakes. The results show that： every earthquake has certain independence when occurring;the two calculable earthquake sequences are non precursory earthquake swarm, that is consistent with the actual; seismogenic faults of the several earthquakes showed by focal mechanism belong to Yinchuan buried fault, and it may be related to a series of minor faults near the buried fault. Then, the authors conclude that local stress adjustment may cause several earthquakes occurring, and there is no relationship between the several earthquakes and the big earthquake occurring in the region in the future. At the same time, the authors can speculate about a possibility of felt earthquakes with similar magnitude still occurring in the region in the future.
出处
《华南地震》
2014年第2期49-55,共7页
South China Journal of Seismology
基金
地震科技星火计划(XH12054Y)
地震行业科研专项(201208009)
关键词
震源机制
余震序列
银川地区
时间丛集
银川隐伏断裂
Yinchuan region
Aftershock sequence
Focal mechanism
Time clustering
Yinchuan buried fault
