新疆喀什-乌恰交汇区潮汐触发地震活动的统计检验

A statistical analysis on tidal triggering of the earthquake in the Kashi-Wuqia intersection area，Xinjiang

摘要:

基于Schuster 检验及Permutation 检验方法，对喀什-乌恰交汇区地震活动受固体潮触发情况进行日尺度及月尺度检验。其中日尺度分别选取引潮力南北分量、东西分量及潮汐体应力作为潮汐曲线。研究结果显示，该地区地震活动均较多的发生于3 种潮汐的最大值( 相位0°) 附近，优势发震相位分别为－ 5. 86°、6. 60° 以及－ 15. 52°，且发生地震的频次随潮汐力的增大而增加; 利用3 种潮汐曲线( 引潮力日尺度南北分量、东西分量以及潮汐体应力) 对所有地震进行Schuster 检验所得pS值分别为10. 52% 、2. 40% 以及2. 06% ，Permutation 检验所得pP值分别为10. 90% 、2. 40% 以及2. 06% ，其中基于引潮力东西分量及潮汐体应力的pS、pP值均低于潮汐触发地震的阈值0. 05。月尺度Schuster 检验pS值及Permutation 检验pP值结果均非常小( 接近于0) ，远低于潮汐触发地震阈值0. 05，优势发震相位φ 为－ 1. 91°，较为接近月尺度下的固体潮最大值0°( 即农历朔、望) 。对潮汐触发地震的统计学检验结果即东西向潮汐触发效应大于南北向触发效应的原因进行了初步解释。

Abstract:

A statistical analysis on earth tide triggered earthquake activity in the Kashi-Wuqia intersection area is studied on the basis of Schuster's test and Permutation test on daily and monthly scale． The north-south，east-west component of the tidal force and tidal body stress are chosen as the tidal curve in daily scale． The results show that the earthquakes occurred more near the maximum 0° of the three kinds of tidal curve，and the predominant tidal phases of the earthquake are － 5. 86°，6. 60° and － 15. 52°，and the frequency of the earthquakes increases with the increase of the tide; with three kinds of tidal curve ( the north-south， east-west component of the tidal force and tidal body stress ) ，the pS of the Schuster's test for all the earthquakes are 10. 52% ，2. 40% and 2. 06% ，and the pp of Permutation test are 10. 90% ， 2. 40% and 2. 06% ． The results of pS and pp based on the east-west component of the tidal force and tidal body stress are below the threshold of tidal triggering of earthquakes 0. 05． In the monthly scale，both the pS and pp are very low ( close to 0 ) ，far below the threshold of tidal triggering of earthquakes 0. 05，and the predominant tidal phase of the earthquake is － 18. 95°， close to the maximum 0° ( new moon and full moon) of the earth tide in monthly scale． With the statistical test of tidal triggering of the earthquake，we preliminary explained why the trigger effect in east-west direction is greater than that in north-south direction．