计算和研究了1976年云南龙陵Ms7.3、Ms7.4双主震产生的完全库仑破裂应力变化及其对后续震群序列的动态和静态应力触发作用.结果显示,龙陵第2主震受到了第1主震的动态和静态库仑破裂应力的触发作用.龙陵双主震的13个后续强余震中,发生在龙陵三角形块体内部的强余震,90%都受到了第1或第2主震的动态库仑破裂应力触发或静态库仑破裂应力触发作用,发生在三角形块体外部的强余震,2/3受到了第2主震的动态库仑破裂应力触发作用.从触发作用的强度和范围上看,第2主震的动态和静态库仑破裂应力触发作用都大于第1主震.就近场而言,受到龙陵双主震的动态和静态库仑破裂应力触发作用的余震数目相当,但动态库仑破裂应力的触发作用范围大于静态库仑破裂应力.
The complete Coulomb failure stress changes caused by the 1976 Ms7.3, Ms7.4 Yunnan Longling double main earthquakes are calculated. And dynamic and static stress triggering effects on the after earthquake sequence are studied. The results show that the second main earthquake is subjected to the triggering effect of dynamic and static Coulomb stresses induced by the first main earthquake. Among the thirteen strong aftershocks of the double main earthquakes, 90% of the aftershocks occurred inside the triangle block are subjected to the triggering effect of dynamic and static Coulomb stresses induced by the first or the second main earthquakes. And 2/3 of the aftershocks occurred outside the triangle block are subjected to the triggering effect of dynamic and static Coulomb stresses induced by the second main earthquakes. The dynamic and static stresses triggering effects of the second main earthquake are stronger than the first main earthquake both in intensity and in extent. In near field the numbers of aftershocks triggered by dynamic and static Coulomb stress are about equal. However the range of triggering effect of dynamic Coulomb stress is larger than that of static Coulomb stress.