【摘要】 为了深入研究中国西南地区地应力特征,文中基于统计学理论,将收集到的地应力资料按照应力测量方法进行分类,得到了西南地区震源机制、应力解除、水压致裂、钻孔塌落、断层滑移等5大类所有点的应力统计表,包含不同应力参数(测试点经纬度、测试深度、测量方法、最大主应力方向、构造类型、应力状态等);对应力资料作最大主应力方向玫瑰花图和矢量分布图,划分应力的不同构造状态,分析地应力随深度的变化关系。结果表明:中国西南地区最大主应力轴方位由北到南呈规则转动的趋势,地应力的构造状态中走滑类型占主导地位,大多数地震的震源深度集中在地下10~30km范围,反映地壳不同深度的主压应力作用方向及地应力构造状态上具有明显的一致性。更多还原

【Abstract】 In order to further study the in-situ stress characteristics in parts of southwestern China,based on statistics theory the collected in-situ stress data is classified according to various stress measurement methods in the paper,a list of all collected in-situ stress is obtained containing focal mechanism,stress relief,hydraulic fracturing,borehole collapsing and fault slip.The data includes different stress parameters consisting of points latitude-longitude,testing depth,measuring method,direction of maximum principal stress,tectonic type and stress state.Rose and vector diagram of the principal stress direction are drawn for the stress data,tectonic stress states are divided,and variation relations between in-situ stress and depth are analyzed.The results show that orientation of maximum principal stress in southwestern China rotates regularly from north to south,strike-slip type has a dominant position in tectonic stress states,and most of the earthquake focal depth is focused within the scope of 10~30km underground,which reflects that the direction of main stress in the earths crust with different depth is consistent with the tectonic stress state.更多还原