Biogenic gas shales, predominantly microbial in origin, form an important class of organicrich shale reservoirs with a significant economic potential. Yet large gaps remain in the understanding of their gas generation, storage, and transport mechanisms, as previous studies have been largely focused on mature thermogenic shale reservoirs. In this study, the pore structure of 18 Antrim Shale samples was characterized using gas adsorption (CO₂ and N₂). The results show that most of the Antrim Shale samples are rich in organic matter content (0.58 wt.% to 14.15 wt.%), with highest values found in the Lachine and Norwood members. Samples from the Paxton Member, characterized by lower organic content, have smaller micropore surface area and micropore volume but larger meso-macro pore surface area and volume. The deconvolution results of the pore size distribution from the N₂ adsorption indicate that all of the tested Antrim Shale samples have similar pore groups. Organic matter in the Antrim Shale hosts micro pores instead of meso-macro pores, while clay minerals host both micro and meso-macro pores. Mineral-related pores play a primary role in the total porosity. The biogenic Antrim Shale, therefore, has different pore structures from other well-studied thermogenic gas shales worldwide.

生物源页岩主要是微生物，形成了重要的一类富含有机物的页岩油藏，具有巨大的经济潜力。然而，由于先前的研究主要集中在成熟的热成因页岩储层上，因此在对天然气的产生，储存和输送机理的理解上仍然存在很大差距。在这项研究中，使用气体吸附（CO ₂和N ₂）。结果表明，大多数安特里姆页岩样品中有机物含量丰富（0.58 wt。％至14.15 wt。％），其中Lachine和Norwood成员中的有机物含量最高。来自Paxton Member的样品的特征在于有机物含量较低，具有较小的微孔表面积和微孔体积，但具有较大的中宏观孔表面积和体积。N ₂孔径分布的反褶积结果吸附表明，所有测试的Antrim页岩样品均具有相似的孔群。Antrim页岩中的有机质具有微孔，而不是中微孔，而粘土矿物则具有微孔和中微孔。与矿物有关的孔隙在总孔隙率中起主要作用。因此，具有生物成因的安特里姆页岩的孔隙结构与世界范围内其他经过充分研究的热成因气页岩不同。