川滇菱形块体西南边界断裂运动特征

Characteristics of fault movement on the Southwest boundary of the Sichuan Yunnan rhombus block

基于地震震源机制断层面解,对处于川滇菱形块体西南缘的红河断裂北段和维西—乔后断裂南段的运动特征进行分析.研究结果表明,红河断裂北段运动性质表现出南北差别,越靠近北端其正倾向滑动特征越明显,维西—乔后断裂南段的运动性质总体具有走向滑动特征,在靠近洱源段落兼有正倾滑运动现象.红河断裂北段和维西—乔后断裂南段具有共同的整体走向滑动、局部正倾滑运动的特征,但维西—乔后断裂南段的走滑运动特征相对更明显.

Based on the fault plane solution of the earthquake source mechanism,the motion characteristics of the northern section of the Honghe fault and the southern section of the Weixi-Qiaohou fault located on the Southwest edge of the Sichuan Yunnan rhombus block were analyzed.The research result shows that the motion properties of the northern section of the Honghe fault show north-south differences.The closer it is to the north-ern end,the more obvious its positive sliding characteristics become.The overall motion properties of the southern section of the Weixi-Qiaohou fault have strike sliding characteristics.In the section near Eryuan,there is also a phenomenon of normal sliding movement.The northern section of the Honghe fault and the southern section of the Weixi-Qiaohou fault share the same characteristics of overall strike sliding and local positive dip sliding,but the strike slip motion characteristics of the southern section of the Weixi-Qiaohou fault are more obvious compared to the positive dip sliding motion.