【摘要】 辽河高升油田莲花油层富含稠油 ,搞清储层中粘土矿物的类型、含量、平面和纵向分布规律对整个稠油油藏开发方案的设计、油层保护、提高采收率等开发措施实施和稠油油藏形成条件等研究都具有极其重要的意义。本文利用X—衍射、电镜、热反应实验对高升油田莲花油层中的粘土矿物进行了系统研究。研究表明 ,莲花油层中的粘土矿物以蒙脱石为主 ,粘土矿物类型、含量分布主要受岩石类型和沉积相控制 ,含油饱和度大小对粘土矿物类型影响不大。蒸汽驱采油会导致储层中蒙脱石的含量减少 ,增加储层的微观非均质性更多还原

【Abstract】 The Lianhua reservoir of Shahejie group(geology period E1) in Gaosheng Oil field, located in Liaohe granen faulting basin, is rich in heavy crude oil, with the burial depth being 1 450～1 700 m.The reservoirs have been under development for 22 years. The company has made great profit from the reservoir development by means of steam flooding technology, but some problems have been found in the reservoir with the technology application, because the difficulty in reservoir development is increasing with the frequency of applying the technology. By the end of 1998 the average steam flooding for every well has been four times, but the more steam flooding, the less satisfactory the efforts to increase the production. Therefore, a more comprehensive study of the types, content, and the horizontal and vertical distribution characteristics of the clay minerals in the reservoir is of most important consequence to the design of the heavy crude oil development, reservoir protection, reservoir evaluation, and enhanced oil recovery (EOR) etc. The clay minerals in Lianhua reservoir are systematically studied by means of X ray diffraction, scan electronic microscope and heat simulation experiments. The Lianhua reservoir is a sediment by gravity flow, with the rock types being gravel, sandstone, and mudstone, and the sedimentary depth being 50～600 m. Lianhua reservoir has excellent physical property, with the porosity being 20%～26% and the permeability being 1～4 μm 2. The studies show that the major clay minerals in Lianhua reservoir are montmorillonite(60%～85%), illite (8%～20%), kaolinite (5%～25%), and chlorite (<5%). The montmorillonite content decreases with the increase of the burial depth, but the kaolinite and illite content are just the opposite, because the porosity fluid in sandstone and gravels more easily circulative than that in mudstone, and the montmorillonite in sandstone can more easily convert into other clays. For the study of the relationship between oil saturation and clay types, the rock is divided into two groups according to the oil saturation degree: the oil saturated and non saturated. The statistical result shows that the clay minerals content and clay types have nothing to do with the oil saturation percentage. The types, contents and distributions of clay minerals are mainly controlled by rock types and sedimentary facies. In general, the absolute content of the montmorillonite increases with decrease of the sedimentary rock grains. The montmorillonite in gravel and sandstone has a relatively lower content than that in mudstone, but there is no much difference between the gravel and sandstone in their contents of montmorillonite. The relative content of montmorillonite in gravel and sandstone is 53.88%～85.99%, with an average of 67.94%, while the content in mudstone is 69.54%～86.59%, with an average of 79.02%. The relative contents of kaolinite distribution decrease in the sequence of gravel, sandstone, and mudstone. But that of the illite is just the opposite. Lianhua reservoir is a turbidity current deposit in lake facies. Sandstone and gravel are mainly distributed in groove and branch groove facies, mudstone and aleurolite in deep lake , groove front margin and interlayer branch groove facies. During the evolving process of the facies from the main groove to branch groove, to the groove front margin, to the interlayer branch groove, and finally to deep lake, the absolute content of clay minerals and the relative content of montmorillonite in Lianhua reservoir increases with the decline of the primary hydraulics. By heat simulation experiments and a comparative study of the distribution characteristics of clay minerals before and after the steam flooding , it is found that the montmorillonite in the reservoir can increase because of kaolinite ’s reaction to carbonate grains. But because the heavy crude oil carries the montmorillonite grains out, there finally is an approximately 1% deduction of the absolute amount of montmorillonite in the reservoir after steam flooding更多还原