摘要：
Ordos Basin is the largest base for low permeable oil/gas exploration and development in China. The low permeable oil/gas accumulation in Ordos Basin featured with poor physical property, strong heterogeneity and complex factors controlling oil/gas accumulation and distribution. Based on reviewing and summarizing the history and experience of low permeability reservoir exploration in Ordos Basin, it indicated that there are two theory systems in studying low permeability reservoir formation at present. One is sedimentary controlling reservoir formation theory, which emphasizes that low permeability reservoir formation was controlled by sedimentary facies, heterogeneity and diagenesis; the other one is dynamics controlling reservoir formation theory, which focuses on oil/ gas migration dynamics in primary migration and secondary migration. At present, it is insufficient to study low permeable oil/gas accumulation because traditional theories emphasize on single factor controlling oil/gas accumulation and corresponding exploration, which can not exactly reveal oil/gas accumulation principle and effectively guide exploration. Similarities and differences between low permeability reservoirs and conventional reservoirs should be paid attention. The sedimentary controlling reservoir formation theory limited to divide sedimentary facies and to establish depositional model; it emphasized on the controls of sedimentary factors to oil/gas accumulation, and ignored the dynamic properties of hydrocarbon accumulation process. Dynamics controlling reservoir formation theory overemphasizes the modeled and formulistic oil/gas fluid migration; it exaggerated and optionally explained the role of oil/gas migration and accumulation record (oil/gas inclusion) and its original geological significance, and ignored the complex of oil/gas migration and the multiplicity of oil/gas inclusion record. It is important to study reservoir geological record and reservoir formation history to summarize oil/gas accumulation principle and to provide important data for oil and gas exploration.%鄂尔多斯盆地是中国规模最大的低渗透油气资源勘探与开发基地,其低渗透油气藏具有油层物性差、非均质性强、油藏成藏因素复杂、油藏分布受多种因素联合控制等特点.在回顾鄂尔多斯盆地低渗透油气藏成藏理论研究和勘探历史经验基础上,认为目前鄂尔多斯盆地低渗透油气藏成藏研究存在两大理论体系,即沉积学控制成藏理论和运移动力学控制成藏理论,前者从沉积特征出发,强调储层砂体沉积相、非均质性和成岩作用在低渗透性油藏形成中的控制作用,后者从石油运移与聚集过程出发,强调运移动力学在初次运移和二次运移中的重要作用.但是目前低渗透油气成藏研究存在一定的局限性和片面性,过分强调了单个地质因素的作用,其中沉积学控制成藏理论局限于沉积相划分和沉积模式建立方面,过多地强调了沉积相对成藏因素静态的控制作用,而忽视了油气成藏过程的动态属性；运移动力学控制成藏理论却过分强调了油气流体运移过程的模式化和公式化,过分夸大和随意解释了油气运移成藏记录——油气包裹体的作用及其原始地质意义,轻视了深部地层条件下油气运移的复杂性和油气包裹体记录的多解性.因此,传统的单因素控制油气成藏理论和相应的勘探研究方法已经不能确切揭示油气富集规律和有效指导勘探工作.低渗透油气藏成藏理论研究趋势是要重视分析油气藏地质记录,动态研究油气藏形成和演化历史过程,总结油气富集规律,为油气勘探战略部署提供重要资料.
