页岩油气高效开发的关键基础理论与挑战

The Key Fundamentals for the Efficient Exploitation of Shale Oil and Gas and Its Related Challenges

为更好地指导我国页岩气资源高效开发,在概述我国页岩气资源和开采现状的基础上,从地质特征预测、安全快速钻井、环保高效开采等方面系统总结了我国页岩气开采面临的工程地质难题,指出页岩非线性工程地质力学特征与预测理论、多重耦合下的页岩油气安全优质钻井理论、页岩地层动态随机裂缝控制机理与无水压裂技术、页岩油气多尺度渗流特征与开采理论等是需要重点解决的关键理论问题,钻采过程中页岩储层物理力学化学特征演化规律与数学表征,多场耦合条件下非连续页岩与钻井完井流体作用机理,页岩地层动态随机裂缝控制、长效导流机制与无水压裂技术,页岩微纳尺度吸附/解吸机制、尺度升级及多场耦合的多相渗流理论等是亟需解决的关键前沿理论问题,并针对各前沿关键力学问题综述了研究进展和发展趋势,对促进我国页岩油气的科学、有效开发具有一定的借鉴作用。

This paper identifies and discusses the multiple geologic engineering challenges involved in shale gas exploitation which include reservoir characterization,safe and fast drilling,environmentallyfriendly and efficient exploitation,and it puts them within a context of China＇s experience in exploring for and exploiting shale gas.The paper elaborates upon the key fundamentals,which include geologic mechanical behavior and prediction theories of non-linear shale engineering,safe and quality shale oil and gas well drilling theories based on multiple coupling,dynamic and random fracture control mechanisms and non-aqueous fracturing technologies of shale beds,and multiscale seepage characteristics and exploitation theories of shale oil and gas.The following advanced theoretical issues should be solved as soon as possible.It was necessary to investigate the evolution rules of physical,chemical and mechanical properties of shale reservoirs and carry out mathematical characterization,analyze the interaction between discontinuous surrounding rocks and drilling and completion fluids under multiple coupling conditions,develop dynamic and random fracture control methods,long-term effective diverting mechanisms and non-aqueous fracturing technologies for shale reservoirs,explore micro-nano scale adsorption and desorption mechanisms of shale,and study multi-phase seepage theories with upscaling and multiple coupling.The paper concludes with a summary of research progress and development trends in the key advanced mechanical issues.This paper serves as a reference and guidance for the scientific and efficient development of shale oil and gas in China.