【作者】 赵伟；

【导师】 姜在兴；

【作者基本信息】 中国地质大学（北京） ， 矿产普查与勘探， 2011， 博士

【摘要】 滩坝砂体是近年来油气勘探的一个新的热点领域,次生孔隙是滩坝砂体中的一种重要的孔隙类型,次生孔隙的产生是形成有效孔隙的重要条件。本文以东营凹陷古近系沙四上亚段滩坝砂体为研究对象,综合运用岩心观察、薄片鉴定、扫描电镜观察、能谱分析、全岩X衍射、岩心物性分析等多种技术方法,结合层序地层划分、沉积体系展布、构造演化史、有机质热演化史、油气成藏史等研究成果,从固体-流体相互作用的过程入手,对滩坝砂体次生孔隙的形成机制和演化过程进行了系统研究,划分了流体演化阶段,建立了次生孔隙成因分布模式,并在此基础上形成了以固体、流体和成岩环境为依据的“五参数固体-流体有效储层评价和预测方法”,根据此方法可以对砂体有效储层的发育情况进行评价和预测。研究区发现的次生孔隙主要为钙质胶结物溶蚀孔隙和石英溶蚀孔隙,属于不同的流体环境下作用的产物。不同成因类型的次生孔隙在平面上分布具有一定的规律性,凹陷南坡砾质滩坝发育带主要是钙质胶结物溶蚀次生孔隙发育,远岸滩坝和中央共振带滩坝主要是石英溶蚀产生的次生孔隙发育,而近岸滩坝和三角洲控制滩坝储层中可见两种类型次生孔隙共存。不同沉积相带次生孔隙类型不同主要是由于不同沉积区固体和流体性质的差异,此外不同成因的次生孔隙共存的现象更反映了流体演化过程的复杂性和阶段性。根据流体来源和流体性质的变化,结合盆地埋藏史、构造演化史和有机质热演化史等,将整个埋藏时期的流体演化划分了五个阶段:初始流体成岩阶段、围岩流体成岩阶段、外来流体成岩阶段、排烃流体成岩阶段和排烃后流体成岩阶段,确定了每个流体演化阶段的流体来源和持续时间。根据不同次生孔隙发育带成岩现象的不同,进一步建立了各个带流体性质、固体颗粒和物性演化的正演模型。总结了影响次生孔隙发育的五个主要参数:方解石、白云石、石英、流体pH值和埋深。依据五个参数之间的相互作用关系,建立了三种矿物随埋深和流体pH值变化的溶蚀-沉淀图版。根据该图版形成了“五参数固体-流体有效储层评价和预测方法”,并通过选取不同次生孔隙发育带的多口重点井对该方法的验证,证明了方法具有较强的适用性和可靠性。最后,利用该方法对博兴洼陷两个代表性开发区块的重点产油层进行了储层的评价和预测,也取得了很好的效果。更多还原

【Abstract】 Beach-bar sand has becoming a very important target of petroleum exploration in recent years. Secondary pore is a momentous style in the sandstone of beach and bar and plays an important role in the forming of effective reservoir. In this article we focus on the case study of beach-bar sand bodies of the upper part of the forth member of Shahejie Formation of Paleogene in Dongying Depression. Based on the integrated research of core observation, thin section identification, SEM observation, SEM/EDX analysis, core X-ray diffraction analysis and core physical properties analysis and so on, combined with sequence stratigraphy, depositional system distribution, tectonic evolution, thermal history of organic matter, and oil and gas accumulation history research results, a systematic study about the formation mechanism and evolution of secondary pore has been done from the research of the solid-liquid process. After this, the fluid evolution can be divided and the distribution pattern of secondary pore genesis can be found. According to the relationship of solid, fluid and diagenetic environments,“evaluation and prediction method of effective reservoir with five parameters of solid-fluid”come into being. Using this method we can evaluate and predict the development of effective reservoir in sand bodies.Secondary porosity which can be found in the study area include calcareous cement dissolved porosity and quartz dissolved pores. They are produced in different fluid environments. Different genetic types of secondary porosity distributed in the plane with a certain regularity: gravelly beach and bar in the southern slope of depression mainly develops calcareous cement secondary dissolution porosity, the bar far from shore and in the central resonance belt mainly develops quartz dissolution secondary porosity, and the bar near shore and controlled by delta develops two types of secondary porosity. The differences of secondary pore developed in different sedimentary facies are mainly due to the difference of solid and fluid characteristics; also it reflects the complexity and stages of the fluid evolution. According to the source of fluid and changes of fluid properties, combing the basin burial history, tectonic evolution history and thermal history of organic matter, fluid evolution could be divided into five stages during the whole burial history, such as diagenetic stage of the initial fluid, diagenetic stage of surrounding fluid, diagenetic stage of external fluid, diagenetic stage of hydrocarbon expulsion fluid and diagenetic stage of fluid after the hydrocarbon expulsion. The source and duration of fluid in each stage can be determined. Depending on the differences of diagenetic phenomenon, forward model of liquid properties, solid and reservoir properties evolution was established in every secondary porosity zone. There are five main parameters which were summarized can influence the content of secondary porosity in sandstone. They are calcite, dolomite, quartz, pH value of fluid and burial depth. Calcite, dolomite, quartz are solid parameters, while the pH value is a fluid parameter and burial depth is a diagenetic environment parameter. Based on the research of interaction among these five parameters, a dissolution-precipitation plate of the three minerals can be established. The X-axis stand for pH and the Y-axis is depth separately. This changed the criteria for the classification of fluid by simple acidic and alkaline in reservoir research. Formed a "evaluation and prediction method of effective reservoir with five parameters of solid-fluid" and it’s applicability and reliability can be confirmed by several wells in every secondary porosity development zone. Finally, we take the key oil production in two typical development blocks as examples, and make an evaluation and prediction of effective reservoir which has achieved good results.更多还原