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为明确纹层发育程度对页岩储层的影响,以渤海湾盆地东营凹陷沙四上—沙三下亚段页岩为研究对象,采用岩心观察、铸体薄片、扫描电镜、高压压汞和低场核磁共振等方法,分析不同岩相页岩的储集空间类型及孔隙结构特征,研究页岩纹层发育程度对储集空间及渗流通道的影响因素.结果表明:渤海湾盆地东营凹陷沙四上—沙三下亚段页岩油储层的储集空间类型由孔隙及裂缝组成,其中孔隙类型主要为粒间孔、粒间微缝、晶间孔和溶蚀孔,裂缝包括层间裂缝、异常压力裂缝和构造裂缝;纹层状页岩的孔隙结构为大孔细喉型,层状页岩的孔隙结构为中孔中喉型;纹层状页岩T2谱呈"三峰"特征,层状、块状页岩T2 谱主要呈"双峰"特征,纹层状页岩样品孔裂隙发育好于层状、块状页岩样品的;纹层发育程度一方面影响页岩储层的孔隙度,页岩的纹层越发育,孔隙度越高,含油性越好;另一方面页岩纹层改善页岩储层的渗流能力.该结果为渤海湾盆地东营凹陷沙四上—沙三下亚段页岩油勘探开发提供参考.

页岩的孔隙特征对页岩油的开采具有重要意义.为探讨博兴洼陷沙河街组页岩油储层的孔隙特征,本文基于高压压汞分析了页岩的孔隙结构及分形特征.研究结果表明:博兴洼陷沙河街组页岩孔隙可分为三类,Ⅰ类为较有利储层、Ⅱ类为不利储层,Ⅲ类为有利储层.基于三种不同模型表征不同尺度下孔径的分形特征,Menger海绵模型适用于表征中小孔、毛管力模型适用于表征中大孔,Sierpinski模型适用于表征各尺度下孔径的分形特征.

To ascertain the adsorption characteristics of coal reservoirs in the Ewirgol mining area of the western margin of Turpan-Hami Basin, this paper systematically collected and sorted the coal rock and coal quality data and isothermal adsorption data and analyzed it. The adsorption characteristics of coal reservoir were clarified and the relationship between the depth, coal rank, coal microscopic components and coal quality with adsorption characteristics were analyzed. The research shows that the Langmuir volume of coal reservoirs in the study area ranges from 14.37 m3/t to 27.84 m3/t, with an average of 25.07 m3/t. The Langmuir pressure falls between 1.14 MPa and 3.45 MPa, with an average of 1.77 MPa. Under the combined action of temperature, pressure, porosity and other factors, the adsorption capacity of coal reservoirs exhibit a positive correlation between with buried depth and a “high-low-high” change law with the increase of coal rank. The adsorption capacity of coal reservoir increases and decreases with the increasing vitrinite content and inertinite content, respectively. The greater the moisture and ash yield in the coal, the weaker the adsorption capacity of coal. On the whole, the adsorption capacity of the coal reservoir in the study area is strong and is evidently dependent on the burial depth, and the deep coal reservoir has a good potential of CBM resources.

The occurrence states of hydrogen sulfide in coal seams are crucial in preventing and controlling hydrogen sulfide emission in coal mines and the safe development of coal bed methane. In this study, the research status of the occurrence states of free-state, adsorbed-state, and water-soluble hydrogen sulfide in coal seams was systematically analyzed. H 2 S anomaly areas in China's coal seams are mainly located in the Carboniferous-Permian and Jurassic series of northern, eastern, central, and northwest regions of China. Bacterial sulfate reduction accounts for most of the hydrogen sulfide anomalies of low-rank coal, while thermochemical decomposition thermal desorption spectroscopy and thermochemical sulfate reduction may also result in hydrogen sulfide anomaly in medium- and high-rank coal. In contrast, magmatism-induced hydrogen sulfide anomalies are rarely found. Absorbed-state hydrogen sulfide anomalies are prevailing, while water-soluble and free-state hydrogen sulfide anomalies are relatively scarce. Coal seam's porosity mainly controls the hydrogen sulfide adsorption, pressure, coalification degree, pore volume, and specific area, while water-soluble hydrogen sulfide is influenced by pressure, sulfate-reducing bacteria, burn, porosity, fractures, water temperature, and hydrodynamic conditions. The fractures in coal seams, their burial depth, coal quality, coal rank, roof, and floor lithology are the main factors controlling the free-state hydrogen sulfide preservation. The absorbed-state hydrogen sulfide in coal seams is mainly mitigated by varying the ventilation mode, increasing the ventilation capacity, spraying alkali fog into the air, and injecting alkali liquid into coal seams for governance.