渝西区块页岩气钻井防漏堵漏技术研究

Research on Leakage Prevention and Plugging Technology of Shale Gas Drilling in West Chongqing Block

川渝地区优质页岩气储量丰富,勘探开发潜力巨大,深层页岩气已逐步成为勘探开发的重要区域,渝西区块地质地貌复杂、埋藏深、缝洞发育明显,嘉陵江与须家河组不整合接触、灰岩云岩岩溶发育、构造裂缝断层发育,井漏复杂事故频发,严重制约了钻井施工提速提效。针对上述工程地质难题,开展了页岩气钻井防漏堵漏技术研究,系统阐述了岩溶勘查、井身结构优化、物理化学类、水泥浆、膨胀管等技术工艺的封堵效果,明确了井漏预防处理措施。目前井漏治理难度大,恶性井漏频繁,综合堵漏工艺技术具备一定效果,但仍需进一步开展堵漏新材料、新工具及配套工艺技术攻关。

Sichuan and Chongqing are rich in high-quality shale gas reserves,with huge potential for exploration and development.Deep shale gas has gradually become an important area for exploration and development.West Chongqing block has complex geological and geomorphic features,such as deep burial depth,obvious fracture and cave development,unconformable contact between Jialing River and Xujiahe Formation,limestone dolomite karst development,and structural fracture and fault development,and frequent occurrence of com-plex well losses,which seriously restrict the speed and efficiency of drilling construction.In view of the above engineering geological problems,the research on leakage prevention and plugging technology for shale gas drilling has been carried out,and the plugging effects of karst exploration,well structure optimization,physical and chemical,cement slurry,expansion pipe and other technical processes have been systematically expounded,and the prevention and treatment measures for well leakage have been clarified.At present,it is difficult to control well leakage,and malignant lost circulation is frequent,so the comprehensive plugging technology has achieved certain results,but it is still necessary to further tackle key technical problem for plugging new materials,new tools and supporting technologies.