Organic matter (OM)-hosted pores are the most prevalent pores in organic-rich shale, in which shale gas is generated and stored. Ascertaining the pore structure of OM and its contribution to the shale pore network provides guidance for understanding deeply the complex pore network, as well as the shale gas flow and storage mechanisms. In this study, the pore structure and heterogeneity of Wufeng–Longmaxi shales and the corresponding isolated OM samples were studied comparatively by scanning electron microscopy (SEM) observations and gas (CO₂ and N₂) physisorption quantification. The Wufeng–Longmaxi shales are rich in OM, with total organic carbon (TOC) contents of 1.48–3.59 wt.%. The SEM-observed microscopic pores were primarily OM-hosted pores and intra-particle pores within clays. Compared to the pore structure per gram of bulk shale, that of isolated OM showed a significantly larger micropore (d < 2 nm) volume and specific surface area (SSA), meso-pore (d = 2–50 nm) and fine macro-pore (50 < d ≤ 80 nm) volume, and Brunauer–Emmett–Teller SSA. Moreover, the pore structure heterogeneity of the bulk shale was much stronger than that of the isolated OM, revealing that pores associated with minerals could enhance the heterogeneity of shale to some extent. The pore size distributions of the bulk shale (1 g) and the corresponding weight-normalized isolated OM (1 g × TOC) were compared. It was revealed that shale pores with diameters smaller than 20 nm were provided by OM together with minerals, while almost all pores with diameters of 20–80 nm occurred within the OM. Overall, the OM and OM-hosted pores provide a vital contribution to the entire pore network of the Wufeng–Longmaxi shale.

在富含有机物的页岩中，有机质（OM）孔隙是最普遍的孔隙，页岩气在其中产生并储存。确定OM的孔隙结构及其对页岩孔隙网络的贡献可为深入了解复杂的孔隙网络以及页岩气的流动和储集机制提供指导。在这项研究中，通过扫描电子显微镜（SEM）观测和气体（CO ₂和N ₂）比较研究了五峰-龙马溪页岩和相应的分离OM样品的孔隙结构和非均质性。）物理吸附定量。五峰—龙马溪组页岩富含OM，有机碳总量（TOC）为1.48–3.59 wt。％。SEM观察到的微观孔隙主要是黏土中的OM孔隙和颗粒内孔隙。与每克块状页岩的孔结构相比，分离的OM的孔结构具有明显更大的微孔（d  <2 nm）和比表面积（SSA），中孔（d  = 2–50 nm）和精细的宏观孔隙。毛孔（50 <  d ≤80 nm）的体积，以及Brunauer–Emmett–Teller SSA。此外，块状页岩的孔隙结构非均质性比分离的OM强得多，这表明与矿物相关的孔隙可以在一定程度上增强页岩的非均质性。比较了块状页岩（1 g）的孔径分布和相应的重量归一化分离的OM（1 g×TOC）。结果表明，OM随矿物一起提供了直径小于20 nm的页岩孔，而几乎所有直径在20-80 nm的孔都在OM内发生。总体而言，由OM和OM承载的孔隙为五峰—龙马溪组页岩的整个孔隙网络做出了至关重要的贡献。