A digital face mapping case study in an underground hard rock mine

摘要

This paper presents a case study of a digital discontinuity mapping system used as a rock mass characterization tool in an underground hard rock mine. This mapping system allows for a fast acquisition of information that can best characterize the geological structural regime without exposing workers to potentially unsafe conditions. This method can be used to overcome some of the shortcomings of traditional mapping methods, such as limited access to rock exposures. Photographic images of the exposed rock mass are introduced into a software package that has been developed to extract potential discontinuity traces using detection algorithms. Detected features that do not describe discontinuity traces are removed from the images using artificial neural networks. Operator intervention can improve the reliability of the system by linking incomplete discontinuity segments. This developed process results in the construction of a discontinuity trace map that can be used for rock mass characterization purposes. The system was employed to construct discontinuity trace maps of twenty 1.8 m by 1.8 m mapping windows from two locations in an underground hard rock mine. The ability of the system to quantify the geomechanical characteristics of the rock mass was evaluated by comparing the results with those of manually drawn discontinuity trace maps. The results of this study have helped to evaluate the digital face mapping system and identify its limitations.