Genesis of Geological Structure and Effect on Gas Occurrence in Changcun Minefield

In order to study gas geological rules of Changcun Minefield,geological structure gradual control theory on gas occurrence was used to analyze formatio n of geological structure,and its effect on gas occurrence was also analyzed combined with a large number of gas geological datas. The results showed that these large throw conducting adjacent aquifers faults of NEE,near EW and SEE were easy to form open faults to release gas on account of present tectonic stress field control. Gas relesaing effect range of fault with 50 m throw was 130 ~140 m. However,these small scale faults of same direction were easy to become favorable location of gas occu rrence,and gas reservoir effect range of fault with 1 m throw was 30 ~ 40 m. These faults of near SN and NNW were always in state of compress-torque to save gas,co mpression and strong shear force leaded deformed-coal develop well near these faults,so it could be concluded that these faults controlled coal and gas outburst distrib ution in deep. Syncline structure was likely to save gas,conversely,and anticlinal structure was not. Most of karstic collapse columns were well-sealed against gas occur rence,but which developed near large throw geologic faults of NEE,near EW and SEE often were poor-sealed against gas occurrence.