摘要
涠洲A油田经过多年注水开发,目前油田综合含水率已达70%,开展水淹过程储层动态变化研究,对于油田后期开发具有重要意义。通过开展一系列储层微观实验,对比同种岩石相水淹前后储层参数特征,结合地质背景开展机理分析,得到以下两点认识:(1)水淹导致储层物性明显变差,孔喉结构非均质性变强,粒内溶孔和铸模孔含量增多,泥质含量降低,黏土矿物含量及类型发生改变;(2)水淹过程中储层物性变化的主控因素为硫酸钡晶体的生成和析出,其次为黏土矿物的水化、膨胀、分散、迁移。注入水与地层水不匹配,导致硫酸钡晶体结晶析出形成沉淀,并堵塞喉道。
After years of waterflooding,the total water cut has grown up to 70%in the Weizhou A Oilfield.It is urgently required to carry out researches on the dynamic changes in reservoir parameters during water-flood process for future development and production.Through a series of reservoir microcosmic experiments,we made a comparison of the reservoir parameters before and after flooding for the reservoir of same lithofacies.Mechanism analysis based on geological background was also carried out.It is concluded that,waterlogging may result in obvious deterioration of reservoir properties,such as strong heterogeneity in pore throat structures,increase in pores and moldic holes,decease in mud content and changes of clay in both content and type;during flooding process,the main factor for the changes in reservoir property is the production and precipitation of barium sulfate crystals,followed by hydration,expansion,dispersion and migration of clay minerals.As the injected water does not match well with the formation water,barium sulfate crystals crystallized and precipitated,eventually clogged up the throat and led to poor physical properties.
作者
王玉
马华帅
郇金来
刘娟
WANG Yu;MA Huashuai;HUAN Jinlai;LIU Juan(Zhanjiang Branch Company of China National Offshore Oil Corporation,Zhanjiang 524057,Guangdong,China)
出处
《海洋地质前沿》
CSCD
2019年第2期43-49,共7页
Marine Geology Frontiers
基金
中海油自有科研项目"复杂断块油藏注水开发剩余油分布规律及主控因素研究"(YXYK-2018-ZJ-02)
关键词
水淹
物性
孔喉结构
黏土矿物
硫酸钡
涠洲A油田
water-flood
physical properties
pore throat structure
clay minerals
barium sulfate
Weizhou A Oilfield
