云南大姚、姚安及附近地区地震活动与潮汐应力的触发关系

Triggering Relationship between Seismic Activity and Tidal Stress in Dayao-Yaoan and its Adjacent Area of Yunnan Province

以云南大姚、姚安及其附近地区8个M>5.0地震序列为研究对象,计算了主震震源断层上的潮汐应力,并通过Schuster潮汐相位角统计检验,分析了该地区地震活动与潮汐应力的触发相关性,进一步确认两者的潮汐应力触发关系。结果显示,7个地震序列的P值小于5%,6个地震序列的潮汐库仑破裂应力为正值。考虑到震源参数的不确定性,8个M>5.0地震序列中,至少5个地震序列与潮汐应力存在一定的触发相关性,说明潮汐应力对该地区地震活动具有一定的潮汐触发作用。

Focused on 8 seismic sequence in Dayao and Yaoan and its adjacent area in Yunnan,we calculated the tidal stresses on the main shock fault plane,and analyzed the relationship betw een seismic activity and tidal stress by Schuster tidal phase angle statistical tests to further confirmed the tidal stress triggering relationship betw een them. The results show that the P value of 7 seismic sequences is less than 5%,and the tidal Coulomb failure stress of 6 seismic sequences is positive. Considering the uncertainty of focal shock parameters,there are at least5 seismic sequence exists certain relevance to tidal stress triggering among 8 M 5. 0 seismic sequence,which shows that the seismic activity are certainly be triggered by tidal stress in the study area.