论文部分内容阅读
通过对1996年3月19日新疆阿图什6．9级地震余震分布特征的研究，分析了这次地震震源破裂过程．并结合柯坪断裂带的构造运动、区域应力场的分布特征以及1972年以来该带的另外3次6级地震的余震分布方向，探讨了柯坪断裂带附近地区不同构造部位震源破裂扩展方向与强震活动的迁移方向．结果表明，本次地震震源破裂为明显的单侧破裂．柯坪断裂带的阿图什震区和柯坪震区，余震分布具有一定规律性，震源破裂基本都为单侧破裂；震源断错以逆断层为主．区内主要受NW向压应力。不同地段强震震源破裂扩展具有明显的区域特征，强余震分布方向是应力集中的体现，它标志着同一构造断裂带附近近期强震活动的迁移方向．在柯坪断裂带上这种规律更为明显。
Through the study of the aftershock distribution characteristics of the Atushi MS 6.9 earthquake in Xinjiang on March 19, 1996, the rupture process of the earthquake source was analyzed. Based on the tectonic movement of Keping fault zone, the distribution of regional stress field and the distribution of aftershocks of three other MS6 earthquakes in the belt since 1972, the relationship between focal rupture propagation direction Strong earthquake activity migration direction. The results show that the earthquake source rupture is obvious unilateral rupture. The Atushu earthquake area and the Keping earthquake area in the Keping fault zone have a certain regularity of aftershock distribution. The source ruptures are basically unilateral ruptures, and the fault sources are mainly thrust faults. The area is mainly subjected to compressive stress in the NW direction. The strong source aftershocks in different areas have obvious regional features. The distribution of strong aftershocks is the reflection of stress concentration, which indicates the migration direction of strong earthquakes in the vicinity of the same tectonic fault zone. This pattern is more pronounced in the Keping fault zone.