Identification of rock fractures using digital Measurement-While-Drilling (MWD) data: a case study

Accurate identification of rock fractures is essential for rock mass stability assessment and grouting design in water conservancy projects. This study proposes a real-time fracture identification method based on digital Measurement-While-Drilling (MWD) data from the Qingyuan Pumped Storage Power Station in Liaoning, China. A digital MWD system was used to continuously record drilling pressure, displacement, rotation speed, current, and penetration rate. After preprocessing, the fracture-response characteristics of these parameters were analyzed, and a Hybrid Fracture Index (HFI) was developed for quantitative fracture identification. Three-dimensional Kriging interpolation was further used to visualize fracture distribution. Comparison with borehole television imaging showed good agreement between HFI anomalies and observed fracture locations. The results demonstrate that digital MWD data can provide an efficient approach for real-time, in-situ fracture identification and spatial characterization in rock masses.