新疆石油地质

新疆石油地质 ›› 2025, Vol. 46 ›› Issue (6): 734-741.doi: 10.7657/XJPG20250609

• 油藏工程 • 上一篇    下一篇

页岩油储集层水平井密切割压裂裂缝非均衡扩展机理

齐洪岩1a,2(), 王振林1b,2(), 郑国庆2, 余佩蓉2, 杨旺旺2   

  1. 1.中国石油大学（北京） a.地球科学学院；b.石油工程学院，北京 102249
    2.中国石油 新疆油田分公司 勘探开发研究院，新疆 克拉玛依 834000
  • 收稿日期:2024-11-14 修回日期:2025-01-09 出版日期:2025-12-01 发布日期:2025-12-05
  • 通讯作者: 王振林 E-mail:qhy@petrochina.com.cn;wzhenl@petrochina.com.cn
  • 作者简介:齐洪岩（1983-），男，山东无棣人，高级工程师，博士研究生，非常规资源评价与预测,（Tel）0990-6240223 (Email) qhy@petrochina.com.cn
  • 基金资助:
    中国石油科技项目(2023ZZ15YJ02)

Unbalanced Fracture Propagation Mechanism During Horizontal Well Intensive Fracturing in Shale Oil Reservoirs

QI Hongyan1a,2(), WANG Zhenlin1b,2(), ZHENG Guoqing2, YU Peirong2, YANG Wangwang2   

  1. 1. China University of Petroleum (Beijing)，a.School of Geosciences; b.School of Petroleum Engineering，Beijing 102249，China
    2. Research Institute of Exploration and Development，Xinjiang Oilfield Company，PetroChina，Karamay，Xinjiang 834000，China
  • Received:2024-11-14 Revised:2025-01-09 Online:2025-12-01 Published:2025-12-05
  • Contact: WANG Zhenlin E-mail:qhy@petrochina.com.cn;wzhenl@petrochina.com.cn

RichHTML

0

PDF

1

摘要： 针对陆相页岩油储集层地质特征，基于内聚力单元的数值计算方法构建水平井密切割压裂裂缝非均衡扩展数值模型，研究簇间距和纹层对多裂缝非均衡扩展的影响，厘清水平井密切割压裂改造中裂缝非均衡扩展的机理。选取页岩油储集层天然露头开展真三轴密切割压裂物理模拟实验，研究裂缝起裂及跨界面扩展力学行为，揭示密切割压裂裂缝与纹层相互作用力学机理。结果表明：页岩油储集层纹层发育程度是影响裂缝网络复杂结构的重要因素，增大簇间距能有效提高纹层及界面的沟通效率；各簇裂缝扩展速率差值随簇间距的增大而减小，且簇间距较小时中部裂缝受应力干扰的影响较大；多簇裂缝的扩展形态互补，合理控制簇间距可以提高裂缝纵向延伸能力，扩大裂缝波及范围，提高页岩油储集层压裂改造效率。

关键词: 页岩油, 储集层, 纹层, 内聚力单元, 水平井, 密切割压裂, 压裂裂缝, 非均衡扩展, 数值模型

Abstract:

In light of the geological characteristics of continental shale oil reservoirs，a numerical model for unbalanced fracture propagation during horizontal well intensive fracturing was constructed using the cohesive zone method to study the effects of cluster spacing and lamina on unbalanced propagation of multiple fractures and then elucidate the mechanism of unbalanced fracture propagation during horizontal well intensive fracturing. True triaxial physical simulation experiment was conducted on samples taken from the field outcrop of shale oil reservoirs to investigate the mechanical behaviors of multi-fracture initiation and cross-interface propagation and thereby reveal the mechanism of mechanical interaction between fractures and lamina during intensive fracturing. Comprehensive analysis indicates that the development degree of lamina in shale oil reservoirs is the key determinant of the complexity of fracture network. Increasing cluster spacing effectively enhances the connectivity of the lamina and interfaces. The difference in propagation rate among fracture clusters decreases with the increase of cluster spacing，and the central fractures are more prominently affected by stress interference when cluster spacing is small. The multiple-clustered fractures exhibit a mutually complementary propagation pattern. Reasonably controlling cluster spacing can improve the vertical extension of fractures，thereby expanding the coverage of fracture system and enhancing the fracturing efficiency in shale oil reservoirs.

Key words: shale oil, reservoir, lamina, cohesive zone, horizontal well, intensive fracturing, induced fracture, unbalanced propagation, numerical model

中图分类号: