致密储层岩石的渗透率应力敏感性研究

发布时间：2018-04-19 04:32

本文选题：渗透率 + 应力敏感　；参考：《西南石油大学》2017年硕士论文

【摘要】：在致密油气藏开发开采过程中,随着油气的不断采出,地层压力降低,储层微裂缝和孔隙发生形变,此时有效应力表现出明显的非线性,以往的线性有效应力理论不能客观的反映开采过程中渗透率随孔隙压力的变化规律以及客观的评价应力敏感性对致密油气藏产能的影响。为此,本文通过对国内外有效应力理论与实验研究的调研,.以致密储层岩石为研究对象开展渗透率有效应力和应力敏感性研究。主要完成的工作和取得的认识如下:(1)进行了渗透率有效应力理论研究,根据渗透率有效应力系数的理论模型参数分析,研究了黏土和裂缝对岩石有效应力系数的影响;(2)完成了岩样的基本物性测试,并采用扫描电镜实验、铸体薄片实验、X衍射实验和压汞实验进行微观特征分析;(3)开展渗透率有效应力实验,研究了孔隙流体类型和裂缝对渗透率有效应力系数的影响,孔隙流体分别采用氮气和地层水,岩样中有2块天然裂缝岩样、3块人造裂缝岩样和5块基质岩样;(4)采用响应面割线法处理实验数据计算渗透率有效应力系数,并分析渗透率有效应力系数的变化范围和变化规律;(5)分别用理论模型和经验模型来研究渗透率与有效应力的关系,得到了应力敏感系数的表达式并明确其物理意义;(6)推导了考虑应力敏感的单井产能模型,根据产量的降低幅度来评价储层的应力敏感性。本次研究根据有效应力的定义和数据分析方法,建立了一套获取渗透率有效应力系数的方法,通过对渗透率有效应力的研究进一步深化了对渗透率有效应力变化规律的认识,并结合岩石的微观特征和有效应力实验结果分析了黏土、孔隙流体类型和裂缝对岩.-石有效应力系数的影响。
[Abstract]:During the development and exploitation of tight oil and gas reservoirs, with the continuous production of oil and gas, the formation pressure decreases, the microfractures and pores of the reservoir deform, and the effective stress shows obvious nonlinearity.The former linear effective stress theory can not objectively reflect the variation of permeability with pore pressure and objectively evaluate the effect of stress sensitivity on the productivity of tight oil and gas reservoirs.Therefore, this paper investigates the theory and experiment of effective stress at home and abroad.Permeability effective stress and stress sensitivity are studied in tight reservoir rocks.The main work and knowledge obtained are as follows: (1) the theoretical study of effective permeability stress is carried out, and the parameters of the theoretical model of effective permeability stress coefficient are analyzed.The effect of clay and fracture on the effective stress coefficient of rock was studied.X diffraction and mercury injection experiments were carried out to study the effect of pore fluid type and fracture on permeability effective stress coefficient.The pore fluid adopts nitrogen gas and formation water respectively, and there are 2 natural fractured rock samples and 3 artificial fractured rock samples and 5 matrix rock samples in the rock samples. The effective stress coefficient of permeability is calculated by using the response surface Secant method to deal with the experimental data.The relationship between permeability and effective stress is studied by theoretical model and empirical model.The expression of stress sensitivity coefficient and its physical meaning are obtained. A single well productivity model considering stress sensitivity is derived and the stress sensitivity of reservoir is evaluated according to the reduction range of production rate.According to the definition of effective stress and the method of data analysis, a set of methods for obtaining effective stress coefficient of permeability has been established in this study. Through the study of effective stress of permeability, we have further deepened the understanding of the law of change of effective stress in permeability.The influence of clay, pore fluid type and fracture on the effective stress coefficient of rock is analyzed based on the microscopic characteristics of rock and the experimental results of effective stress.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE312

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