多分层煤层渗透率及压裂钻孔位置确定

从煤层在地质历史形成过程中所具有的多分层特点出发，论证了多分层煤层的总渗透率不仅取决于各分层渗透率的大小，还取决于分层厚度在煤层总厚度中所占的比例。进而分析得出，在采用钻孔注水压裂法提高煤层渗透率和增加瓦斯外排量时，注水压裂钻孔的合理布置位置应位于相对渗透率小、厚度相对比较大的分层中。该分析结果对预防煤与瓦斯突出及瓦斯抽放均具有现实的指导意义。

Penetration-rate characteristic of multistratum coal bed and reasonable arrangement of hydraulic fracture bores

Based on the multistratum characteristic of coal bed that formed out of the coal bed formation in geologic history, the paper establishes that mutistratum coal bed's penetration-rate depends not only on penetration-rate of delamination, but also the proportion of delamination thickness in the total thickness of coal beds. The analysis concludes that the use of hydraulic fracture to increase the penetration-rate of coal bed and the gas evacuation content involves a reasonable arrangement of hydraulic fracture bores in the coal delamination of a greater thickness and a lower penetration-rate. The result presents significance to preventing coal and gas from breaking out and perfoming gas exhaust evacuation.