A workflow is presented that integrates unmanned aerial vehicle (UAV) imagery with discrete fracture network (DFN) geometric characterization and quantification of fluid flow. The DFN analysis allows for reliable characterization and reproduction of the most relevant features of fracture networks, including: identification of orientation sets and their characteristics (mean orientation, dispersion, and prior probability); scale invariance in distributions of fracture length and spatial location/clustering; and the distribution of aperture values used to compute network-scale equivalent permeability. A two-dimensional DFN-generation approach honors field data by explicitly reproducing observed multi-scale fracture clustering using a multiplicative cascade process and power law distribution of fracture length. The influence of aperture on network-scale equivalent permeability is investigated using comparisons between a sublinear aperture-to-length relationship and constant aperture. To assess the applicability of the developed methodology, DFN flow simulations are calibrated to pumping test data. Results suggest that even at small scales, UAV surveys capture the essential geometrical properties required for fluid flow characterization. Both the constant and sublinear aperture scaling approaches provide good matches to the pumping test results with only minimal calibration, indicating that the reproduced networks sufficiently capture the geometric and connectivity properties characteristic of the granitic rocks at the study site. The sublinear aperture scaling case honors the directions of dominant fractures that play a critical role in connecting fracture clusters and provides a realistic representation of network permeability.

提出了将无人飞行器（UAV）图像与离散裂缝网络（DFN）的几何特征和流体流量量化相集成的工作流。DFN分析可对裂隙网络最相关的特征进行可靠的表征和再现，包括：识别方向集及其特征（平均方向，离散度和先验概率）；裂缝长度和空间位置/聚类分布的尺度不变性；以及用于计算网络规模等效渗透率的孔径值分布。二维DFN生成方法通过使用乘法级联过程和裂缝长度的幂律分布来明确再现观察到的多尺度裂缝聚类，从而尊重了现场数据。使用亚线性孔径与长度的关系和恒定孔径之间的比较，研究了孔径对网络规模等效渗透率的影响。为了评估所开发方法的适用性，将DFN流量模拟校准到泵送测试数据。结果表明，即使在小规模的情况下，UAV勘测也可以捕获流体流动表征所需的基本几何特性。恒定孔径法和亚线性孔径法都只需极少的校准就可以与抽水试验结果很好地匹配，这表明所复制的网络足以捕获研究地点花岗岩岩石的几何和连通性特征。