引言云南省和四川省是中国西南地震活动最活跃的地区。一般认为,该地区的构造应力场受到印度—西藏板块碰撞的控制,指向东北正对该地区中心的铃状碰撞带就说明了这一点。地区构造特征及地貌受到现代活动碰撞的强烈影响。在这一地区东北部,鲜水河断裂带,安宁河断裂带、小江断裂带组成一走向从西到北的活跃的断裂系。在中部,红河断裂从西北延伸 Introduction Yunnan and Sichuan provinces are the most active seismic areas in southwest China. It is generally accepted that the tectonic stress field in this area is controlled by the collision of the Indo-Tibet plate and points to the bell-shaped collision zone of the northeast facing the center of the area. Regional tectonic features and topography are strongly influenced by the collision of modern activities. In the northeastern part of the region, the Xianshuihe fault zone, Anninghe fault zone and Xiaojiang fault zone form an active fault system that runs from west to north. In the middle, the Red River fault extends from northwest