Zou Linhao, Su Yinao, Xu Xingsheng, Li Wei, Zhao Huan, Zhang Mingxiu, Jiao Shengjie
The Key Laboratory of Continental Shale Oil and Gas Accumulation and Efficient Development, Northeast Petroleum University, Daqing, Heilongjiang, China.
National Key Laboratory of Continental Shale Oil, Daqing, Heilongjiang, China.
PLoS One. 2025 Jul 30;20(7):e0328689. doi: 10.1371/journal.pone.0328689. eCollection 2025.
The development of unconventional oil and gas resources is increasingly shifting toward heterogeneous reservoirs with complex permeability distributions, making the effective control of hydraulic fracture propagation patterns critical for optimizing production. To this end, this study establishes a 3D multilayered heterogeneous reservoir model using the finite element method to analyze fracture mechanisms. The impacts of permeability heterogeneous, injection rate, and fracturing fluid viscosity on fracture morphology are systematically investigated, and the elasticity coefficient method was used to evaluate the influence weights of each parameter.The main conclusions are as follows: (1) Permeability distribution is the core factor controlling the fracture propagation direction, with HPL dominating the extension path while MPL and LPL show limited efficiency. (2) An increase in the number of permeability layers inhibits the overall expansion of cracks, and the shape of the cracks gradually changes to rectangular. (3) Higher injection rates significantly expand fracture area, whereas fracturing fluid viscosity ≥50 mPa·s stabilizes fracture morphology. (4) The elastic coefficient method identifies injection rate, permeability heterogeneous, and fracturing fluid viscosity as the key control parameters in order. This work provides theoretical guidance for optimizing hydraulic fracturing parameters in complex geological settings.
非常规油气资源的开发正日益转向渗透率分布复杂的非均质油藏，这使得有效控制水力裂缝扩展模式对于优化产量至关重要。为此，本研究采用有限元方法建立了三维多层非均质油藏模型，以分析裂缝机理。系统研究了渗透率非均质性、注入速率和压裂液粘度对裂缝形态的影响，并采用弹性系数法评估各参数的影响权重。主要结论如下：（1）渗透率分布是控制裂缝扩展方向的核心因素，高渗透层主导延伸路径，而中渗透层和低渗透层的作用有限。（2）渗透率层数增加会抑制裂缝的整体扩展，裂缝形状逐渐变为矩形。（3）较高的注入速率显著扩大裂缝面积，而压裂液粘度≥50 mPa·s可稳定裂缝形态。（4）弹性系数法确定注入速率、渗透率非均质性和压裂液粘度依次为关键控制参数。这项工作为复杂地质条件下优化水力压裂参数提供了理论指导。
