【摘要】 利用所采样品的扫描电镜、核磁共振、氮气吸附、X射线衍射、镜质组反射率(Ro)、总有机碳质量分数(TOC)及显微组分等实验测试资料,探讨了黔北凤冈地区下志留统龙马溪组页岩的孔隙结构特征。结果表明:研究区页岩中TOC差异较大,Ro介于1.363%～2.647%,黏土矿物质量分数较大;页岩中常见有机质孔和微裂缝,形状多为圆形、长条狭缝形及墨水瓶形,孔隙度为6.53%～8.33%;页岩孔隙以孔径为2～50 nm的介孔为主,BET比表面积相对较大,总体积平均为0.019 62 cm3/g;孔隙的发育受有机质成熟度、有机质丰度和矿物组分影响,随着黏土矿物质量分数、总有机碳质量分数的增加,页岩孔容及比表面积呈现增长的趋势,而当石英等脆性矿物质量分数、镜质组反射率增加时,孔隙度、孔隙总体积则随之减小。更多还原

【Abstract】 By using the experimental data of scanning electron microscopy(SEM), nuclear magnetic resonance, nitrogen adsorption, X-ray diffraction, Ro, TOC and maceral composition, the pore structure characteristics of Lower Silurian Longmaxi Formation shale in Fenggang area, northern Guizhou were discussed. The results show that the organic carbon content of shale in the study area is quite different, with vitrinite reflectance of 1.363% -2.647% and high content of clay minerals; the common organic pore and micro-crack in the shale have the mainly round, long slit and ink bottle shapes, with the porosity of shale ranging from 6.53% to 8.33%; the shale pore is mainly mesoporous, with pore diameter of 2-50 nm, larger BET specific surface area of pore and the average total volume of 0.01962 cm3/g; the development of pore is influenced by maturity of organic matter,organic matter content and minerals content. With the increase of clay minerals and TOC, the pore volume and specific surface area of shale show an increasing trend; but when Roand brittle minerals such as quartz increase, the porosity and total pore volume decrease.更多还原