1. School of Resource and Geosciences,China University of Mining & Technology,Xuzhou　 221116,China; 2. East China Company,SINOPEC,Nanjing　210011,China; 3. Transportation Institute,Inner Mongolia University,Hohhot　 010070,China

测试资料显示延川南区块具有丰富的致密砂岩气资源,为提高研究区单井产气量和非常规天然气资源开发效益,在分析煤层气-砂岩气赋存特征及开发条件基础上总结出了砂岩气层识别特征,然后从地层压力的角度论证了深部煤层气和致密砂岩气合采地质可行性,探讨了煤系气合采的适配性技术工艺。研究表明:砂岩气层主要位于上古生界山西组和下石盒子组,岩性以长石岩屑质石英砂岩为主,具有低孔-低渗的特征;高产气层具有低GR、低DEN、低CNL、高R_T、高AC的测井响应特征,位于R_T-AC交汇图版右上部;砂岩气与煤层气合采层间跨度上限值位于155~180 m,当层间跨度<20 m时适合采用合压合采方式,当层间跨度在20~50 m时,应采用限流法分层压裂工艺,当层间跨度大于50 m时,应采用下分割器分层压裂法。该技术在现场得到广泛应用,大幅提高了单井产气量。

The test data show that the southern block of Yanchuan is rich in tight sandstone gas resources. In order to increase gas production in single well and exploit the benefit of unconventional natural gas resources in the study area, based on the analysis of the characteristics and development conditions of the coalbed gas-sandstone gas,the identifica- tion characteristics of the sandstone gas are summarized. Then,from the perspective of formation pressure,the geolog- ical feasibility of deep coalbed methane and tight sandstone gas production is demonstrated,and the suitability produc- tion technology of coal series gas is discussed. The results show that the sandstone gas is mainly located in the Upper Paleozoic Shanxi formation and Lower Shihezi Formation,characterized by long lithic quartz sandstone with low porosi- ty and low permeability. The high yield gas area has the logging response characteristics of low GR,low DEN,low CNL,high RT and high AC,which is located on the upper right part of RT -AC intersection diagram. The upper limit of interlayer span for sandstone gas and coalbed methane combined mining is between 155-180 m. The co-exploitation is suitable for the interlayer span is

国家科技重大专项资助项目(2011ZX05035-006)；

FU Yutong,YUAN Junhong,CUI Bin,et al. Key technology on co-exploitation of coalbed methane and tight sandstone in south area of Yan- chuan[J]. Journal of China Coal Society,2018,43(6):1747-1753.