致密砂岩储层应力敏感性评价实验研究  

An experimental study on stress sensitivity of tight sandstone reservoirs

作　　者：祁丽莎[1] 王雨[1] 张承洲[1] 戈月[1] 汪伟英[1] 

机构地区：[1]长江大学油气资源与勘探技术教育部重点实验室,湖北武汉430100

出　　处：《石油化工应用》2013年第10期18-21,共4页Petrochemical Industry Application

摘　　要：低渗透储层具有较强的应力敏感性。这个现象用常规的油气田开发理论和油气渗流力学理论是难以解释的,只有考虑多孔介质变形才能合理解释这些特殊现象。通过对低渗透天然、人工造缝及填砂处理岩样,进行应力敏感性评价,得出:(1)天然岩样初始渗透率越小,随着净应力的增加,渗透率损害率越大,应力敏感性越强;(2)在净应力较低的情况下,随着围压增大,岩样渗透率急剧下降;当净应力增大到一定值时,渗透率下降速度减慢;(3)岩样经加压—卸压过程,渗透率无法得到完全恢复,随着加减压次数的增加,应力滞后效应减弱;(4)填砂岩样的缝越宽,随着净应力的增加,渗透率损害率越大,应力敏感程度越强。填砂岩样随着净应力的增加,其渗透率损害率比造缝未填砂岩样的损害率小。The low permeability reservoir vary with strong stress sensitivity. This phenomenon is difficult to explain with conventional theory of the development of oil-gas fields and oil-gas seepage mechanics theory,only consider the deformation of the porous medium can rea- sonably explain these phenomena.In this paper, we do stress sensitivity evaluation by low permeability no fracture,artificial joints and fill sand processing samples, obtain that：（ 1 ）With the increasing net stress,the initial permeability of no fracture rock is smaller,permeability damage rate will higher,as well as the stress sensitivity.（2）In the case of lower net stress, the permeability of sample simple sharply decline with the increased of confining pressure,when the net stress increases to a certain value,the permeability decline slowed down. （3）After pressure-relief process,the permeability of rock simple can not be fully restored.With the number of pressure-reducing increasing,the stress hysteresis effect became weak. （4）With the increasing net stress,permeability damage rate of the sand filling core sample is smaller than artificial crack core sample.

关 键 词：应力敏感 低渗透 人工造缝 填砂 净应力 

分 类 号：TE132[石油与天然气工程—油气勘探]