Abstract:
Based on the macrostructural character and statistical analysis of small faults in Panjiaan Mining Area,it is concluded that two or more phases of tectonic movement had been undergone,and two sets of stress field were existed after the Permo-Carboniferous coal-bearing strata deposited in Huang-Huai region.The geological structures of two phases are compounded transversally at a large angle, and it is the main cause which resulted the uneven floor of coal basin.At the same time,an extensional area with the orientation of NNE-NEE was formed,the structural track in this orientation shows the compressional or compresso-shear nature,and it is a better watertight structure;in a stress compressional area with the orientation of SN-NW-NWW,the normal faults with the dip angle larger than 45° in this orientation show mostly tensional or tensiono shear nature,and it is a better water-storaging and producing structure and degassing structure.