页岩有机质纳米力学性质研究进展

页岩有机质纳米尺度下的力学行为目前不够明确且利用常规实验仪器无法准确获得,表征其纳米尺度下的力学性质,对于搭建微观-宏观岩石力学模型和实现高效水力压裂是极具现实意义的。基于近年国内外关于页岩有机质纳米力学性质表征等方面所取得的研究进展,总结了目前常用的表征技术、力学性质主要特征及主控因素。综合结果表明,纳米压痕和原子力显微镜是目前表征纳米力学性质常用的技术与方法,两者在精度、分辨率、设备技术等方面都存在各自的优势或缺陷;目前有机质纳米力学性质的测定主要集中在弹性模量和硬度,成熟度和温度在不同程度上改变着有机质的内部结构,从而改变其力学性质;提出了"多尺度""多技术""多角度""多学科"等工作设想与建议。

Progress in characterization of nanoscale mechanical properties of organic matter in shale

At present the mechanical behavior of shale organic matter at nanometer scale is neither clear nor able to be accurately obtained by conventional experimental instruments. It is of great practical significance to characterize the mechanical properties at nanometer scale for building a micro-macro rock mechanics model and realizing high efficiency hydraulic fracturing. Based on the recent advances in characterization of nanoscale mechanical properties of organic matter in shale at home and abroad, commonly used characterization techniques, main characteristics and main controlling factors of mechanical properties are reviewed and summarized in this paper. It is shown that nano-indentation and atomic force microscope are the commonly used techniques and methods to characterize nano mechanical properties at present, both of which have their own advantages or defects in precision, resolution, equipment technology and so on. At present, determination of nanomechanical properties of organic matter mainly focuses on elastic modulus and hardness. Maturity and temperature change the internal structure of organic matter to varying degrees, thus changing its mechanical properties. In the end, the paper puts forward some ideas and suggestions for the exploration and development of shale gas in China.