页岩的成储机理及页岩油的可流动性研究——以松辽盆地、济阳坳陷为例

Inspired by the successful development of shale oil and gas in America, the exploration of shale oil and gas in our country is vigorously strengthened. But compared with the continuously breakthrough of shale gas wells, drilling wells aiming at shale oil, even higher yielding firstly, production is decreasing quickly, far short of the mud interbed of the shale oil in America, no benefit on the exploitation. One of the reasons lies in the lacustrine shale rich oil of eastern China is usually thick and pure. Can this kind of shale, what condition can be effective reservoir of oil? The key problems of two aspects need to be studied. First, the size, distribution of the shale pore and throat, connectivity and its evolution; Second, we must clear the oil can, how many can flow in shale, which is related to the mechanism of shale oil in the occurrence, state. And there are lack of effective research techniques and methods on the second question. Therefore, intends to introduce the molecular dynamics theory and lattice Boltzmann method into geological study, which shows the potential applications in nanomaterials research, in order to know and quantitative characterization of shale oil in occurrence mechanism, the adsorption quantity, movability, and its relationship with pore throat size. Moreover, indicates the mechanism of shale reservoir for oil and the grading evaluation criterion and provides theoretical guidance for shale oil effective exploration and development.

受美国成功开发页岩油气的启示，我国大力加强了对页岩油气的探索。但与页岩气探井的不断突破相比，针对页岩油的钻井即使获得较高初产，产量也递减太快，远达不到美国泥砂互层致密页岩油的效果，无法效益开采。原因之一在于我国富含油的东部湖相页岩一般较厚较纯。那么这种泥页岩能否、什么条件下能够成为油的有效储层呢？这需要研究两方面的关键问题：一要认识页岩孔、喉的大小、分布、连通性及其演化；二要明确油在页岩中能否、有多少能够流动，而这又与油在页岩中的赋存机理、状态有关。而对后一问题目前还缺少有效的研究技术和手段。因此，本题拟探索将在纳米材料研究中初步展示应用潜力的分子动力学理论和格子Boltzmann方法引入地质研究中，以期认识并定量表征油在页岩内赋存机理、吸附量、可动量、可流动性及其与孔喉大小的关系，从机理上揭示页岩能否成为油的储层、可能的下限及分级评价标准。从而为页岩油能否、如何有效勘探开发提供理论指导。

我国页岩油资源潜力巨大，显示了良好的勘探前景，但迄今勘探开发还没有获得实质性的突破。针对页岩油的钻井即使获得较高初产，产量也递减太快，远达不到美国泥砂互层致密页岩油的效果，无法效益开采。原因之一在于我国富含油的东部湖相页岩一般较厚较纯、成熟度较低、油质较重，页岩油可动性较差。那么这种泥页岩能否、什么条件下能够成为油的有效储层呢？这需要研究两方面的关键问题：一要认识页岩孔、喉的大小、分布、连通性及其演化；二要明确油在页岩中能否、有多少能够流动，而这又与油在页岩中的赋存状态、机理有关。依托本重点基金，综合利用各类高分辨率的分析仪器和技术手段，系统、深入地剖析了页岩的矿物组成、孔-喉-缝的大小、分布、连通性及演化。在此基础上，构建了不同岩相页岩数字岩心三维模型及页岩无机非均质性/脆性评价技术，建立了3项分级/分类标准（泥页岩岩相分类标准、页岩油资源分级评价标准、泥页岩成储下限及分级评价标准），阐明了页岩的成储机理；通过油-岩吸附润湿实验、分子模拟、机理剖析和数值模拟相结合的技术，认识了页岩油的赋存机理，建立了页岩有机非均质性/含油性评价技术、页岩油游离量/可动量评价技术，揭示了页岩油可动性及其影响因素；在上述研究的基础上，评价了靶区的页岩油气资源潜力、建立了基于页岩物性甜点、含油性/可动性甜点和工程甜点的甜点综合评价理论和技术，并在济阳、松辽研究靶区以及江汉、冀中、辽河等页岩油区进行了实际应用。