湖相、海相泥页岩孔隙分形特征对比

在松辽盆地湖相泥页岩低温氮气吸附实验的基础上，利用 FHH 模型探讨了湖相泥页岩纳米级孔 隙结构分形维数与比表面积、平均孔径及 TOC 含量的关系，进一步对比了湖相与海相泥页岩孔隙分形 维数特征。 结果表明：①湖相、海相泥页岩纳米级孔隙均具有明显的分形特征，且大孔隙（孔径为 5～ 100 nm）结构复杂，其分形维数高于小孔隙（孔径小于 5 nm）。 ②湖相泥页岩纳米级孔隙结构相对简单， 分形维数小于海相泥页岩。 ③分形维数与 TOC 含量呈正相关关系，湖相泥页岩有机质丰度对分形维数 影响较小。 ④湖相泥页岩分形维数 D1 与平均孔径具有明显的线性关系，表明 D1 可以反映湖相泥页岩 孔隙结构特征；海相泥页岩分形维数 D2 与孔隙比表面积具有明显的指数关系，表明 D2 可以反映海相 泥页岩孔隙比表面积特征。

Fractal characteristics of lacustrine shale and marine shale

Based on the low temperature nitrogen adsorption test of lacustrine shale in Songliao Basin, FHH model was used to discuss the relations of fractal dimension of nano-pore structure with specific surface area, average pore size and TOC content, and then compare the characteristics of fractal dimension between lacustrine shale and marine shale. The result shows that: （1） the nano-pores of the lacustrine shale and marine shale have obvious fractal characteristics, and the large pore （5-100 nm）, with a bigger fractal dimension, shows a higher degree of complexity than the small pore （less than 5 nm）; （2）the nano-pore structure of lacustrine shale is relatively simple, and its fractal dimension is less than that of the marine shale; （3）the fractal dimension is positively correlated with TOC content, and the TOC of lacustrine shale has weaker influence on fractal dimension; （4）the fractal dimension （D1） of lacustrine shale has a significant linear relationship with the average pore size, which shows that D1 can reflect the pore structure features of lacustrine shale, while the fractal dimension （D2） of marine shale has an exponential relationship with the specific surface area, which shows that D2 can reflect the pore specific surface area characteristics of marine shale.