摘要
为阐明甲烷原位燃爆压裂载荷对页岩储层的微观改性特征,开展高温-动载协同作用下页岩微纳米孔隙结构的演化特征研究,选取典型页岩样品,综合应用3D轮廓测量、原子力显微镜(AFM)、扫描电镜(SEM)和X射线衍射(XRD),分析高温-动态冲击作用后的页岩碎块的宏微观粗糙特性、孔裂隙结构及矿物组分随高温的变化特征。结果表明:随温度升高,页岩断面毫米级粗糙度先略有降低后急剧升高。随温度升高,页岩有机质纳米孔减少,石英中出现复杂裂缝,碳酸盐矿物产生气孔,黏土矿物层间结构破坏,页岩体孔隙度由常温的1.488%逐渐上升至700℃的1.997%。不同高温下页岩物性组成差异显著,XRD定量分析结果显示,石英的质量占比升高,方解石和白云石总占比降低,从微纳米尺度说明燃爆载荷对页岩储层有改性效果。
To elucidate the micro-scale modification mechanisms of shale reservoirs by methane in-situ explosive fracturing,the evolution characteristics of micro scale and nano scale pore structures in shale were investigated under synergistic effects of high temperature and dynamic impact.This study selected typical shale samples and comprehensively applied 3D contour measurement,atomic force microscopy(AFM),scanning electron microscopy(SEM)and X-ray diffraction(XRD)to study the macro-micro roughness characteristics,pore and crack structures and mineral composition changes with temperature of shale fragments after high temperature and dynamic impact.The results show that with the increase of temperature,the millimeter-scale roughness of shale section first decreases slightly and then rises sharply.The organic matter nano-pores in shale decrease,complex cracks appear in quartz,gas pores are produced in carbonate minerals,interlayer structures of clay minerals are destroyed,and the porosity of shale body gradually increases from 1.488%at room temperature to 1.997%at 700℃.The mineral composition of shale is significantly different at different high temperatures.XRD quantitative analysis shows that the mass ratio of quartz increases while that of dolomite and calcite decreases.This study proves that high-temperature combustion has a modification effect on shale roughness and pore-crack from the micro-nano scale.
作者
余旭
王宇
翟成
刘厅
徐吉钊
孙勇
YU Xu;WANG Yu;ZHAI Cheng;LIU Ting;XU Jizhao;SUN Yong(School of Safety Engineering,China University of Mining and Technology,Xuzhou Jiangsu 221116,China;National Engineering Research Center for Coal Gas Control,China University of Mining and Technology,Xuzhou Jiangsu 221116,China;School of Low-Carbon Energy and Power Engineering,Xuzhou Jiangsu 221116,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2023年第10期137-146,共10页
China Safety Science Journal
基金
国家重点研发计划项目(2020YFA0711800)
国家自然科学基金青年科学基金资助(52104233)
中央高校基本科研业务费专项资金资助(2023KYJD1007)。
关键词
高温热效应
动态冲击
页岩
微纳米
孔隙结构
演化特征
燃爆压裂
粗糙度
high-temperature effect
dynamic impact
shale
micro-nano scale
pore structure
evolutionary characteristics
explosion fracturing
roughness
