基于盐溶和蠕变作用的含盐储层裂缝导流能力变化规律研究与应用  

Research and Application of Changing Rule of Fracture Flow Conductivity in Salt-Bearing Reservoirs Based on Salt Dissolution and Creep

作　　者：俞天喜 王雷 陈蓓蓓 孙锡泽 李圣祥 朱振龙 Yu Tianxi;Wang Lei;Chen Beibei;Sun Xize;Li Shengxiang;Zhu Zhenlong(PetroChina Xinjiang Oilfield Company,Karamay,Xinjiang 834000,China;School of Petroleum Engineering,Yangtze University,Wuhan,Hubei 430100,China;Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering,Wuhan,Hubei 430100,China)

机构地区：[1]中国石油新疆油田分公司,新疆克拉玛依834000 [2]长江大学石油工程学院,湖北武汉430100 [3]油气钻采工程湖北省重点实验室,湖北武汉430100

出　　处：《特种油气藏》2023年第6期157-164,共8页Special Oil & Gas Reservoirs

基　　金：国家自然科学基金“致密油水平井SRV与基质耦合变质量流动模型研究”(51504038)。

摘　　要：含盐储层压裂后裂缝导流能力快速下降,导致产量快速下降,提升裂缝导流能力成为提高该类油藏开发效果的关键。以准噶尔盆地玛湖区域含盐储层为研究对象,基于储层的矿物组分数据,对储层含盐程度进行分类,并以此为基础,对储层的蠕变性能和盐岩溶解规律,以及支撑剂粒径、铺砂浓度和流体介质等因素对导流能力的影响进行研究,并定量分析了储层蠕变作用、盐溶作用和支撑剂嵌入对裂缝宽度的影响。研究表明:盐类矿物含量越高的盐岩,其蠕变力学行为特征越明显;温度越高、流体矿化度和黏度越小,盐溶解速率越大;裂缝缝宽主要受支撑剂的嵌入作用、含盐储层的蠕变作用和裂缝表面盐溶作用的共同影响,支撑剂的嵌入作用和含盐储层的蠕变作用导致缝宽减小,裂缝表面盐岩由于溶蚀作用使缝宽增加。在工艺上采用清水配置压裂液和高浓度、大粒径支撑剂可以显著提升裂缝的导流能力。该研究成果在现场试验取得了成功,为含盐储层的高效压裂指明了方向。The rapid decline of fracture flow conductivity after fracturing of salt-bearing reservoirs leads to the rapid decline of production,so the enhancement of fracture flow conductivity becomes the key to improve the development effect of this type of reservoir.By taking the salt-bearing reservoir in Mahu area of Junggar Basin as the research object,and based on the mineral component data of the reservoir,the salt content of the reservoir was classified,and based on this,the creep performance of the reservoir and the dissolution law of the salt rock,as well as the influence of the proppant particle size,the sanding concentration,and the fluid medium on the flow conductivity were investigated,and the effects of the creep effect of the reservoir,the salt dissolution effect,and the embeddedness of the proppant on the fracture width were quantitatively analyzed.The study shows that:The higher the salt mineral content of the salt rock,the more obvious the characteristics of its creep mechanical behavior;the higher the temperature,the lower the fluid mineralization and viscosity,and the higher the rate of salt dissolution;the fracture width is mainly affected by the embedment effect of the proppant,the creep effect of the salt-bearing reservoir and the salt dissolution effect on the fracture surface,and the embedment effect of the proppant and the creep effect of the salt-bearing reservoir lead to a decrease in the fracture width,and the fracture width increases due to the dissolution effect of the salt rock on the fracture surface.The fracturing fluid and high-concentration,large-size proppant prepared by using clear water can significantly enhance the fracture conductivity.The research results have been successfully tested in the field and show the direction for efficient fracturing of salt-bearing reservoirs.

关 键 词：含盐储层 蠕变 盐溶 裂缝导流能力 支撑剂 玛湖 准噶尔盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探]