新疆石油天然气 ›› 2023, Vol. 19 ›› Issue (4): 20-28.DOI: 10.12388/j.issn.1673-2677.2023.04.003

• 油气勘探 • 上一篇    下一篇

玛湖风城组高含盐储层水力压裂裂缝扩展规律

  

  1. 1.中国石油新疆油田分公司工程技术研究院(监理公司),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。

  • 出版日期:2023-12-01 发布日期:2023-12-04
  • 作者简介:潘丽燕(1992-),2019年毕业于西南石油大学油气田开发工程专业,硕士,工程师,目前从事储层改造方面的科研工作。(Tel)18892987633(E-mail)panliyan@petrochina.com.cn

Fracture Propagation Law of Hydraulic Fracturing in High-Salinity Reservoir of Fengcheng Formation in Mahu #br#

  1. 1. Research Institute of Engineering Technology,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China;

    2. College of Petroleum Engineering,Yangtze University,Wuhan 430100,Hubei,China;

    3. Hubei Key Laboratory of Drilling and Production Engineering for Oil and Gas,Wuhan 430100,Hubei,China.

  • Online:2023-12-01 Published:2023-12-04

摘要:

玛湖风城组地层含盐量高,导致压裂施工压力高、水力裂缝穿透盐层扩展难度大、加砂难度大等问题。基于相似准则制备等效含盐岩样开展真三轴压裂实验,并基于有限元法和内聚力单元法开展含盐储层裂缝扩展数值模拟研究,探索了含盐量、黏度、排量等因素对裂缝扩展行为的影响。研究结果表明,与常规砂岩相比,含盐储层破裂压力更高,塑性更强,纯盐隔层的存在会阻碍裂缝纵向扩展;压裂液黏度越小,对含盐储层的溶蚀越强,施工压力就越低;排量越高,压裂摩阻越高,施工压力越高。现场应采用清水配置高黏(120 mPa·s)压裂液和大排量(单簇排量5 m3/min)施工,实现水力裂缝有效穿透纯盐隔层并形成较大缝宽。研究成果对玛湖地区含盐储层的改造具有重要指导意义。

关键词:

含盐储层, 岩石力学特征, 裂缝扩展, 物理模拟实验, 数值模拟, 玛湖风城组

Abstract:

The high salt content of Fengcheng Formation in Mahu leads to high operating pressures, difficulty in fracture propagation when penetrating salt layers, and increased difficulty in adding proppant. True triaxial fracturing experiments are carried out on equivalent salt-bearing rock samples prepared according to similarity criteria, and fracture propagation in salt-bearing reservoirs is numerically simulated using the finite element and cohesive element methods. The influence of salt content, viscosity, pump rate, and other factors on fracture propagation is explored. The results show that the fracture opening pressure of salt-bearing reservoirs is greater than that of conventional sandstone reservoirs, and their plasticity is stronger. The existence of pure salt interlayers hinders the longitudinal propagation of fractures. The lower the fluid viscosity , the stronger the dissolution of the salt-bearing reservoir and the lower the operating pressure. The higher the pump rate, the higher the fracturing friction and the operating pressure. In field, high viscosity fluid (120 mPa·s) with clean water and high pump rate (5 m3/min per single cluster) have been adopted to achieve effective penetration into pure salt barriers and form wider fractures. These results have important guiding significance for the stimulation of salt-bearing reservoirs in Mahu area.

Key words:

salt-bearing reservoir, rock mechanics characteristics, fracture propagation, physical model experiment, numerical simulation, Fengcheng Formation in Mahu

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