CAJ | 학술논문

页岩储层渗透率极低，富含黏土矿物，压缩性较致密砂岩储层更大，为进一步研究页岩储层的应力敏感机制，对宁夏六盘山盆地和内蒙古雅布赖盆地三块页岩岩芯进行应力敏感评价实验。结合岩石动力学实验、X 射线衍射分析、场发射扫描电镜图像分析和高压压汞实验对页岩岩芯的矿物组分、力学性质及微观孔隙结构进行研究，并分析影响应力敏感的主要因素。研究结果表明，有效应力与渗透率关系满足乘幂式；页岩泥质含量越高，杨氏模量越低，应力敏感系数越大；页岩储层普遍发育的纳米级片状孔隙在有效应力作用下呈现强应力敏感；高压压汞实验表明孔喉半径为10～50 nm的孔隙分布频率较高，当对渗透率起主要贡献的孔隙分布在这一范围内时，应力敏感强，当对渗透率起主要贡献的孔隙为大孔时，应力敏感弱。
혈암저층삼투솔겁저，부함점토광물，압축성교치밀사암저층경대，위진일보연구혈암저층적응력민감궤제，대저하륙반산분지화내몽고아포뢰분지삼괴혈암암심진행응력민감평개실험。결합암석동역학실험、X 사선연사분석、장발사소묘전경도상분석화고압압홍실험대혈암암심적광물조분、역학성질급미관공극결구진행연구，병분석영향응력민감적주요인소。연구결과표명，유효응력여삼투솔관계만족승멱식；혈암니질함량월고，양씨모량월저，응력민감계수월대；혈암저층보편발육적납미급편상공극재유효응력작용하정현강응력민감；고압압홍실험표명공후반경위10～50 nm적공극분포빈솔교고，당대삼투솔기주요공헌적공극분포재저일범위내시，응력민감강，당대삼투솔기주요공헌적공극위대공시，응력민감약。
Clay-rich shale rock reveals greater compressibility than tight sandstone. Experiments have been conducted on Liupanshan—Yabrai shale core samples to select appropriate correlations to represent permeability as a function of effective stress. Mineralogical,mechanical properties and microscopic pore structure were analyzed by rock dynamics mechanics experiments,X-ray diffraction analysis,field emission scanning electron microscope image analysis and high pressure mercury injection to investigate stress sensitivity mechanism of shale reservoir. The results show that the exponentiation curve fit the relationship of effective stress and permeability well;The core with high clay content,low Young′s modulus present relative high stress-sensitivity and larger stress-sensitivity coefficient;shale reservoirs with nanoslot pores and throats exhibit highly stress-sensitive because of the irreversible deformation of easy-compressed throats. An increase in mesopore permeability contribution is correlated with an increase in stress sensitivity.