恩洪矿区古构造应力场特征及演化

On the basis of the regional tectonic background research in the study area, through the analysis of characteristics of the joints growth shows that the orientation preferred of joints is NE, second orientation are NNW and NWW. Based on the statistical analysis of conjugate joints system, under the control of the regional tectonic stress, the tectonic stress field in late into coal period of study area can be divided into three main period: In Indochina period the principal stress direction is S - N, In late Yanshanian - early Himalayan period the principal stress direction is NNW - SSE, In late Himalayan period the principal stress direction is NWW - SEE.