鄂尔多斯盆地陇东地区延长组长7储层特征研究

发布时间：2018-06-29 05:04

本文选题：鄂尔多斯盆地 + 陇东地区　；参考：《东北石油大学》2015年硕士论文

【摘要】：鄂尔多斯盆地是一个整体沉降、坳陷迁移的大型多旋回克拉通盆地。晚三叠纪盆地生成了很复杂的生储盖组合,类别有很多,从湖盆形成到后来的繁荣到最后的萎缩期,都很符合油气藏形成的地质条件,湖盆最大的扩张时期是长7区,这个时期具有湖水深、水域广的特点,在这个时期发育100米左右的油页岩,为生油岩系,这套油页岩是中生代陆相生油的基础。在发展的晚三叠世陆相湖泊全盛时期,在半深湖-深湖相带中发育了大面积的延长组长7段优质烃源岩,该套烃源岩是盆地内最好的生油岩,外观呈黑色、点火可燃,鄂尔多斯盆地三叠系延长组长7层一直是作为盆地内最主要的烃源岩进行研究。陇东地区位于盆地西南部,长7期湖盆鼎盛时位于湖盆中心,处于半深湖到深湖的沉积环境,早期研究认为长7层主要发育小规模的浊积岩,岩性致密,难以形成有效储层。然而,近年来,石油和天然气的勘探表明,与西南部三角洲共生的浊积岩含有着丰富的油气资源,规模相当大,特别是新的地质勘探资料和地质信息的积累,以及岩性油勘探技术的应用发展,长7已成为重要的接替层系,但目前长7层的沉积特征、砂体发育及展布、石油富集规律及控制因素等认识不足,特别是对沉积微相及储层的微观孔隙结构涉及较少,孔隙结构仍是油气储集层微观物理研究的核心内容,由于孔隙结构的复杂性,储层孔隙结构的研究也在朝着多种技术方法综合应用的方向发展。本文通过分析储层砂体展布特征,成岩作用,孔隙结构及渗流特征来进行研究。受特殊而复杂的沉积、演化背景影响,尤其是湖相浊积成因使得陇东地区长7层表现出了一系列特殊的储层特征,例如:储层致密、孔隙结构复杂、流体赋存及渗流规律复杂等。陇东地区长7层前期的勘探、开发实践也证明此类储层开发难度很大,开发区单井产量低、能量传导慢、储量动用比较困难。因此,开展陇东地区长7储层特征的研究,尤其是储层微观孔隙结构特征研究对于明确相对的优质储层的控制因素,优化储层改造方向,建立高效开发技术对策均具有重要的指导意义。
[Abstract]:The Ordos basin is a large polycyclic craton basin with integral subsidence and depression migration. The late Triassic basins generated very complex assemblages of source, reservoir and caprock, and there are many types of assemblages. From the formation of the lake basin to the later prosperity to the last shrinking period, they all accord with the geological conditions for the formation of oil and gas reservoirs, and the largest extension period of the lake basin is Chang7 area. This period is characterized by deep lake and wide water area. During this period, oil shale is developed about 100 meters, which is the source rock series, which is the basis of Mesozoic continental oil generation. During the peak of the late Triassic continental lacustrine, a large area of high quality source rocks of the 7 member Yanchang formation were developed in the semi-deep lacustry-deep lacustrine facies zone. This set of source rocks is the best source rock in the basin, with a black appearance and flammable ignition. The 7 layers of Yanchang formation of Triassic in Ordos Basin have been studied as the main source rocks in the basin. The Longdong area is located in the southwest of the basin, and in the center of the lake basin at the peak of the Chang7 period, and in the sedimentary environment from the semi-deep lake to the deep lake. The early studies showed that the Chang 7 layers mainly developed small scale turbidite with dense lithology, so it is difficult to form an effective reservoir. However, in recent years, oil and gas exploration have shown that the turbidite, which is symbiotic with the southwestern delta, is rich in oil and gas resources and has a considerable scale, especially the accumulation of new geological exploration data and geological information. As well as the application and development of lithologic oil exploration technology, Chang7 has become an important replacement series, but at present, the sedimentary characteristics of Chang 7 layer, the development and distribution of sand bodies, the regularity of petroleum enrichment and the controlling factors are not well understood. Especially for sedimentary microfacies and micropore structure of reservoir, pore structure is still the core of microphysical research of oil and gas reservoir, because of the complexity of pore structure, The study of reservoir pore structure is also developing towards the direction of comprehensive application of various technical methods. In this paper, the characteristics of reservoir sand distribution, diagenesis, pore structure and percolation are analyzed. Influenced by special and complex sedimentation and evolution background, especially the origin of lake turbidite, Chang7 formation in Longdong area shows a series of special reservoir characteristics, such as tight reservoir, complex pore structure, Fluid occurrence and percolation are complicated. The exploration and development practice in the early stage of the 7 layers in Longdong area also proved that the development of this kind of reservoir is very difficult, the production of single well in the development zone is low, the energy conduction is slow, and the reserve production is relatively difficult. Therefore, the research on reservoir characteristics of Chang7 reservoir in Longdong area, especially the study of reservoir micro-pore structure characteristics, is helpful to clarify the control factors of relatively high quality reservoir, and to optimize the direction of reservoir reconstruction. It is of great significance to establish the countermeasure of high-efficiency development technology.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

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