The microfracture-pore structures and water-rock interactions of eight samples of three typical lithofacies (three limestone, three wackestone, and two mudstone) from the Lower Eagle Ford Formation have been investigated using an integrated methodology. The methods used were X-ray diffraction (XRD), total organic carbon (TOC) content, pyrolysis, thin-section petrography, scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), spontaneous water imbibition, and water vapor & nitrogen physisorption. Petrophysical properties such as organic richness, maturity, mineral composition, types and patterns of microfractures and pores, porosity, pore-throat size distribution, pore size distribution, pore connectivity, water adsorption and desorption behavior were determined from these methods, and the results compared among the three lithofacies. For example, the three limestone EAS samples and three wackestone DM samples show a low porosity range from 2.02–3.35%, whereas the two mudstone VRU samples exhibit a much large average porosity of 11.7% by MIP results. Nitrogen physisorption results show that pore size distributions have a good similarity in N₂ adsorption volume for the samples with similar lithology. Microfractures are morphologically divided into seven types, with their definitions & pictorial examples presented and possible formation mechanisms proposed. In addition, the water vapor physisorption behavior and their controlling factors are discussed. The water adsorption capacity shows a positive relationship (R² = 0.90) with clay content and a negative relationship (R² = 0.99) with carbonate content. In general, this integrated study of microfracture-pore structure characterization and water-rock interaction provides some insights of water vapor adsorption behavior in different lithofacies and whether microfractures could be an important pathway for fluid flow.

已经使用综合方法研究了下伊格尔福特组的三种典型岩相（三种石灰岩、三种泥岩和两种泥岩）的八个样品的微裂缝-孔隙结构和水-岩相互作用。使用的方法是 X 射线衍射 (XRD)、总有机碳 (TOC) 含量、热解、薄片岩相学、扫描电子显微镜 (SEM)、压汞孔隙率法 (MIP)、自吸水和水蒸气和氮气物理吸附。通过这些方法确定了有机物丰富度、成熟度、矿物组成、微裂缝和孔隙的类型和模式、孔隙度、孔喉尺寸分布、孔径分布、孔隙连通性、水吸附和解吸行为等岩石物理性质，并对三种岩相的结果进行了比较。例如，三个石灰岩 EAS 样品和三个细砂岩 DM 样品显示出 2.02-3.35% 的低孔隙度范围，而根据 MIP 结果，两个泥岩 VRU 样品显示出 11.7% 的大得多的平均孔隙度。氮物理吸附结果表明，孔径分布在 N 中有很好的相似性₂岩性相似样品的吸附量。微裂缝在形态上分为七种类型，并给出了它们的定义和图示示例，并提出了可能的形成机制。此外，还讨论了水蒸气物理吸附行为及其控制因素。吸水能力 与粘土含量呈正相关（R ² = 0.90）， 与碳酸盐含量呈负相关（R ² = 0.99）。总的来说，这种对微裂缝-孔隙结构表征和水-岩相互作用的综合研究为不同岩相中的水蒸气吸附行为以及微裂缝是否​​可能成为流体流动的重要途径提供了一些见解。