为了阐明断层封闭性对煤层产气量的控制作用,利用断层泥比率(SGR)与泥岩涂抹潜势(CSP)分析了沁水盆地柿庄南区块3条典型断层的侧向封闭性,在此基础上,分析了煤层气并距断层面的距离与产能之间的相关关系.研究认为,发育规模较小的逆断层(延伸长度＜2 000 m,断距＜50m)受到一定的挤压作用,封闭性较好(SGR＞50％,CSP＞15 m),井距断层面距离与煤层产气量呈负相关关系;发育规模较大的逆断层(延伸长度＞5 000 m,断距＞60 m)所受挤压作用更为强烈,煤储层遭受破坏,封闭性中等(SGR＜50％,CSP＜12 m),随井距断层面距离的增加,煤层产气效果逐渐向好;寺头正断层上盘受应力破坏作用较大,使得下盘封闭性优于上盘,且下盘产气效果更好,煤层产气量随井距断层面距离的增加而呈现升高的趋势.%In order to illustrate the control effect of fault sealing capability on the coalbed methane production,the shale gouge ratio (SGR) and the clay-smear potential (CSP) are used to analyze lateral sealing capability of three typical faults in southern Shizhuang Block,Qinshui Basin.On basis of the former initial results,relationship between the distance to fault and coalbed methane well productivity has been analyzed.The result shows that the reverse fault with relatively small development scale (extended length＜2 000 m,fault throw＜50 m) has suffered squeezing action at some extent.It has good sealing capability (SGR＞50％,CSP＞ 15 m).There is a negative correlation between the distance and coalbed methane production.The reverse fault with large development scale (extended length＞5 000 m,fault throw＞60 m) has suffered squeezing action more strongly.The coalbed methane reservoir is destroyed.The sealing capability (SGR＜50％,CSP＜ 12 m) is moderate.The gas production will rise with the distance to fault increasing.The hanging wall of Sitou fault is destroyed more strongly.The sealing capability of the footwall is better than that of the hanging wall.The coalbed methane production at the footwall of Sitou fault is higher.It has a upward trend with the distance increasing.
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