通过岩心、显微薄片及电镜样品的观察,结合定量分析测试结果,对有机质在页岩形成、演化及储层发育中重要作用进行研究.研究表明:有机质利于碳酸钙的沉淀,主要由底栖黏结、浮游黏结及生物颗粒3种形式形成碳酸盐,形成的岩石类型包括骨架岩、黏结岩和颗粒灰岩;有机质利于铁质络合物的形成,有机质热演化形成微环境促进碳酸盐矿物的黄铁矿交代;在埋藏演化过程中,有机质演化产生有机酸,对不稳定矿物进行溶蚀,继而发生重结晶作用,影响方解石的晶体大小和形态;有机质直接或间接地产生大量有效的储集空间,有利于页岩孔隙网络的形成,继而影响页岩的储集物性;页岩油产量受总有机碳含量(TOC)影响,建议页岩油形成并具备工业可采能力的TOC下限值为2%,同时也需要富有机质页岩具有稳定的厚度,还应考虑页岩矿物组成及岩石类型、镜质体反射率Ro等因素.%Based on well cores, microscopic sections, scanning electron microscope samples and the relative analysis data, the significances of organic matters on deposition process, diagenesis and shale reservoir were systematically studied. The study shows that organic matters are conducive to the precipitation of calcium carbonate, mainly in terms of benthic stick-knot, planktonic bonding and biological particles to form carbonate. Organic matters can promote the formation of the organic-iron complex, and the micro environment formed during organic matters thermal evolution can promote metasomatism of car-bonate minerals by pyrite. During the burial, organic matters produce organic acids, which may cause the dissolution and re-crystallization of calcite, and further control the calcite crystal size and conformation. Organic matters can generate abundant storage pores directly or indirectly, which is very important for the formation of pore networks in the shale and for the reser-voir physical properties. The analyses show that the shale oil production is closely related to the TOC content, which increa-ses simultaneously with the TOC content. The study suggests that for the shale reservoir formation and industry capacity, the lower limit of TOC content is 2%, and an effective thickness of organic-rich shale needs to be reached. In addition, the min-eral composition, lithofacies, burial depth, Ro also need to be considered.
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