吉木萨尔芦草沟组致密油储层渗吸驱油特性

为评价吉木萨尔地区芦草沟组致密油储层的渗吸驱油潜力,利用井底岩心结合扫描电镜、接触角仪、核磁共振、X射线荧光能谱等仪器,对储层影响渗吸驱油效率的关键因素孔隙结构、润湿特性进行评价分析,并在传统自发渗吸实验的基础上结合核磁共振技术,研究该地区储层自发渗吸特征以及渗吸驱油采收率.结果表明:该地区储层润湿性与流体接触历史密切相关,同时层间含油性对液体渗吸特征影响显著;吉木萨尔地区芦草沟组储层孔隙主要以粒间孔隙为主,矿物颗粒分选良好,储层纹层高度发育,但主要由岩性差异形成,层理微裂隙发育程度不高;渗吸作用对储层岩心大、小孔隙内部原油均具有一定动用能力,综合渗吸采收率约23％,渗吸驱油作用在该地区具有一定的增产潜力.

Research on the imbibition displacement characteristics in tight oil reservoir of Lucaogou Formation, Jimsar

To investigate the imbibition displacement characteristics in Lucaogou Formation, Jimsar, scanning electron microscope, contact angle instrument and nuclear magnetic resonance apparatus were adopted to investigate the pores and wettability characteristics. Moreover, based on the traditional imbibition experiment, the nuclear magnetic resonance technique was adopted to further investigated the imbibition characteristics and imbibition recovery rate. Results show that the wettability of the formation is closely related to the fluid contact history. The pores in samples are consist of intergranular holes, and the grain sorting is quite well. The imbibition volume is affected by oil saturation. The bedding is highly developed but the bedding fractures are less developed and it is formed by lithologic difference. The oil in small pores and larger pores could both partially be displaced by imbibition, and the comprehensive imbibition recovery rate is about 23%, and the imbibition displacement effects could have good potential in this area.