Complex interactions between hydraulic fractures and natural fractures often result in highly complex fracture networks that might lead to bypassed resources damaging the economic viability of developments. In this study the impact of natural fractures of the formation on production from hydraulically fractured wells is studied using a recently developed fracture upscaling method (FUM). By capturing the distribution of complex fracture networks using FUM, a novel idea of changing the well orientation to optimise recovery is proposed. It is shown that with a natural fracture spacing of 15 m a small change in well orientation up to $30°$ from the standard orientation can increase the recovery by up to 15% for natural fractures at an angle of at least $60°$ with ${\sigma }_{hmax}$. The increased recovery is a result of the natural fractures and stress orientation complementing each other to assist the propagation of hydraulic fractures deeper into the formation. It is also shown that as natural fracture density increases (fracture spacing decreases) the effect of changing the well orientation becomes more significant. Changing the well orientation when there are two perpendicular planes of natural fractures is also investigated. However, no optimal orientation can be found in these cases, suggesting there needs to be a strong average directionality of the natural fractures in the reservoir to support a beneficial well orientation change. A simple economic analysis shows a small well orientation change can allow a larger well spacing which could lead to a direct reduction in the cost of developing a shale reservoir. The results also show the positive effect this has on the NPV of the project with different gas prices, and a rapid positive NPV status reducing the risk of investment.

水力裂缝和天然裂缝之间复杂的相互作用通常会导致高度复杂的裂缝网络，这可能导致绕过资源，损害开发的经济可行性。在这项研究中，使用最近开发的裂缝放大方法 (FUM) 研究了地层的天然裂缝对水力压裂井产量的影响。通过使用 FUM 捕获复杂裂缝网络的分布，提出了一种改变井向以优化采收率的新想法。结果表明，天然裂缝间距为 15 ma 时，井向的变化很小，可达$30°$ 从标准方向可以将至少 15% 的天然裂缝的采收率提高 15% $60°$ 和 ${\sigma }_{H米\mathrm{一种}X}$. 增加的采收率是天然裂缝和应力方向相辅相成的结果，有助于水力裂缝深入地层。还表明，随着天然裂缝密度的增加（裂缝间距减小），改变井方向的影响变得更加显着。还研究了当天然裂缝有两个垂直平面时改变井的方向。然而，在这些情况下无法找到最佳方向，这表明储层中天然裂缝需要有很强的平均方向性，以支持有利的井方向变化。一个简单的经济分析表明，一个小的井向变化可以允许更大的井距，这可以直接降低开发页岩油藏的成本。