曙光油田S266区块大孔道识别及分布规律研究

发布时间：2018-03-08 15:36

  本文选题：大孔道　切入点：扇三角洲前缘　出处：《东北石油大学》2017年硕士论文　论文类型：学位论文

【摘要】：长期注水开发作用下,高含水油田油层受到注水不同程度的冲刷作用,导致储层孔渗性发生一定程度变化。部分井层受水洗破坏严重,形成大孔道,从而造成注入水的无效循环,使储层非均质程度加剧,严重影响储层内部剩余油的挖潜。研究大孔道识别方法及大孔道分布规律对高含水期油田的剩余油挖潜具有重要意义。本文主要以曙266区块杜家台油层组为例,在沉积学、开发地质学、油层物理学等理论指导下,首先研究了研究区目的层的主要地质特征,曙266区块属于构造-岩性油气藏,目的层杜家台油层组主要属于扇三角洲前缘沉积,岩石类型以岩屑质长石砂岩和长石质岩屑砂岩为主。胶结物含量较低,以泥质胶结为主,岩石相对疏松。研究了本区块大孔道的识别特征。在动态资料上,吸水百分数远大于临层的井层、随时间增加单层注水百分数持续增加的井层、含水率在某一时间突然增高的井层等均指示大孔道的存在;在测井曲线上则表现为自然电位幅度值、声波时差值升高、井径扩大,电阻率曲线出现幅度值和幅度差下降等。建立了测井资料解释渗透率、孔隙度、平均孔喉半径等参数的模型,利用聚类分析和判别分析确定了大孔道的五级分类划分方法,从I到V级,大孔道性质变差。最后在分析大孔道形成条件的基础上,研究了大孔道的分布规律,I类大孔道首先最易于出现在厚层水下分流河道中下部,或非河道砂中部核心位置;II、III类大孔道分布较为广泛,包括河道中部、宽阔的席状砂内部,IV、V类大孔道多分布在河道砂、席状砂边缘、分流间湾及狭窄的席状砂内部。
[Abstract]:Under the action of water injection for a long time, the reservoir in high water cut oil field is scoured by water injection to different degrees, which leads to the change of reservoir porosity and permeability to a certain extent. As a result, the invalid circulation of injected water is caused, and the heterogeneity of reservoir is aggravated. It is very important to study the method of large pore channel identification and the distribution law of large pore channel to exploit the remaining oil potential in high water-cut oil field. This paper mainly takes Dujiatai formation of Shu266 block as an example in sedimentology. Under the guidance of development geology, reservoir physics and other theories, the main geological characteristics of the target layer in the study area are studied. The Shu266 block belongs to the tectonic-lithologic reservoir, and the Dujiatai reservoir formation of the target layer mainly belongs to the fan delta front sedimentation. The main rock types are lithic feldspathic sandstone and feldspathic lithic sandstone. The content of cementation is relatively low, and the muddy cementation is dominant, and the rock is relatively loose. The percentage of water absorption is much larger than that of the adjacent layer, and the layer with the increase of single-layer water injection percentage continuously increases with time, and the wells with a sudden increase in water cut at a certain time all indicate the existence of a large pore channel. On the log curve, the amplitude of natural potential, the difference of acoustic time, the enlargement of well diameter, the amplitude of resistivity curve and the decrease of amplitude difference are shown. The interpretation permeability and porosity of logging data are established. Based on the model of average pore throat radius and other parameters, the five-level classification and division method of large channels is determined by cluster analysis and discriminant analysis. The properties of large channels become worse from I to V. Finally, based on the analysis of the formation conditions of large channels, In this paper, the distribution of large channels is studied. First of all, large channels of type I are most likely to appear in the middle and lower part of a thick underwater distributary channel, or in the core of non-channel sand center. The distribution of large channels of type III is relatively extensive, including the middle part of the channel. The wide table-shaped sand interior with IVV type macroporous channel is distributed in channel sand, sheet sand edge, distributary bay and narrow sheet sand interior.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.13
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本文编号：1584492