【作者】 贾屾；

【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， 2012， 硕士

【摘要】 随着常规油气资源逐渐减小，非常规油气的勘探开发显得日益重要，其中页岩油气勘探潜力巨大，有着广阔的勘探前景。沾化凹陷是济阳坳陷泥页岩油气藏最发育的地区之一，以生油为主，到目前为止，已有多口探井获得工业油流，但是对于泥页岩储层的形成规律研究很少，认识不足，缺乏有效的评价方法，因此有必要针对泥页岩岩石学特征、储集特征以及影响泥页岩储层发育的各种因素进行系统的研究，建立一套泥页岩储层的评价方法，对研究区内泥页岩储层分布的有利区域进行预测，从而指导下一步的研究工作及勘探目标评价。本文在岩芯、薄片以及扫描电镜观察的基础上，结合X-衍射，有机地化测试等各种分析化验资料，将研究区沙三下亚段泥页岩划分为4大类7种类型，分别为：纹层状粘结岩、纹层状泥灰岩、块状泥灰岩、纹层状灰质页岩、块状灰质泥岩、粉砂质泥岩、块状泥岩。研究区泥页岩储集空间主要有3种孔隙和4种裂缝，孔隙包括：有机质演化孔、重结晶晶间孔以及粘土矿物晶间孔；裂缝包括：构造裂缝、异常压力裂缝、矿物收缩裂缝、层间微裂缝。影响本区泥页岩储层发育的因素有四个，分别为：岩性和岩石矿物组成、有机质含量及赋存方式、构造作用以及成岩作用。岩性对泥页岩储层的影响很大，通过对不同岩性所发育的储集空间类型以及相对含量的分析，可以将本区泥页岩储层定性的分成三类，一类储层包括纹层状粘结岩、纹层状泥灰岩以及纹层状灰质页岩三种岩性；二类储层包括块状泥灰岩以及块状泥岩；三类储层包括块状灰质泥岩以及粉砂质泥岩两类。其中，构造裂缝密度与方解石含量呈正相关关系，矿物收缩缝主要集中于粘土矿物中，层间缝则主要发育在纹层状泥页岩中。研究区有机碳含量高，多位于1%-4%，有机质含量高，有利于裂缝的发育；有机质的赋存方式对油气的储集以及运移起到重要作用，本区泥页岩中有机质主要有三种赋存方式，分别为：A模式-连续的条带状、B模式-断续较连通的条带状以及C模式-孤立的短条带状。构造作用对于构造裂缝的形成影响巨大，通常距离断层越近，裂缝发育越密集。成岩作用对于储层起到一定的改造作用。本区泥页岩处于中成岩阶段A期，粘土矿物转化、成烃作用以及重结晶作用对泥页岩储层有较大影响。综合影响泥页岩储层发育的四大因素，对有利区进行预测。层序1低位体系域储集空间最为发育，是勘探的重点层段，其中纹层状粘结岩是最好的勘探目标。更多还原

【Abstract】 The exploration and development of unconventional oil and gas resources arebecoming increasingly important with conventional oil and gas resources graduallydecreasing, in which shale oil and gas resources have broad prospects for explorationbecause of the huge potential. Zhanhua Sag is one of the most developed areas ofshale hydrocarbon reservoirs in Jiyang Depression, which mainly generates oil, and sofar several prospecting wells have produced commercial oil flow in Zhanhua Sag, butpeople have done very little research on the formation law of the shale reservoir andlack effective evaluation methods. So it is essential to study on shale petrologiccharacteristics, reservoir features in shale, and various factors that affect the shalereservoir. Then one method of evaluating shale reservoir should be established topredict favorable areas which can offer a great help for the further exploration andresearch.In the paper, on the basis of core observation, thin section identification, andscanning electron microscopic analyses, combined with a variety of laboratory datasuch as X-diffraction, organic geochemical testing and so on, the shale in the lowerthird member of Shahejie Formation in the study area should be divided into4majorcategories and7types, which are laminated bondstone, laminated marl, massive marl,laminated calcareous shale, massive calcareous mudstone, silty mudstone, andmassive mudstone. There are mainly there kinds of pores and four kinds of fracturesin the shale. Pores include organic matter pores, recrystallized intercrystal pores andclay mineral intercrystal pores; fractures involve structural fractures, abnormalpressure fractures, mineral shrinkage fratures and interlaminar fractures. The factorsthat affect the development of the shale reservoir consist of lithology and mineralcomposition, content and occurrence of organic matter, tectogenesis and diagenesis.Lithology has a significant influence on the shale reservoir. By the analysis ofreservoir space types and their relative content developed in different kinds oflithology, the shale reservoir can be qualitatively divided into there categories: thebest reservoir includes laminated bondstone, laminated marl and laminated calcareousshale; the second-best reservoir includes massive marl and massive mudstone; theworst reservoir includes massive calcareous mudstone and silty mudstone. Studies show that there is a positive correlation between the density of structural fractures andthe content of calcite; mineral shrinkage fratures mainly exist in the clay mineral;interlaminar fractures are dominately developed in the laminated shale. TOC of theshale in the study area is high, mostly1%-4%, which is beneficial to produce fractures.The occurrence of organic matter also plays an important role on the oil and gasreservoir and migration. There are three main occurrences, which include dence andlaterally continuous layers (mode A), sparse and laterally continuous layers (mode B),sparse and laterally discontinuous layers (mode C). Tectogenesis contributes a lot toproduce structural fractures. Generally the closer away from the fault, the moreintensively structural fractures develop. Diagenesis plays a certain role on improvingthe shale reservoir. The shale is in the middle diagenetic stage A, in which claymineral transformation, generation of hydrocarbon and recrystallization have a greaterimpact on the shale reservoir.Finally, the four factors that affect the shale reservoir are integrated to predictfavorable areas. The low-stand system tract in the sequence1is the best layer toexplore, in which the reservoir space is most developed and the lithology of laminatedbondstone is the best exploration target.更多还原