Application of SfM-MVS for mining geology: Capture set-up and automated processing using the Dugald River Zn-Pb-Ag mine as a case study

Abstract

The use of structure-from-motion, multi-view stereo (SfM-MVS) in the mining industry is well-established for capturing digital data on surface. However, the application of SfM-MVS in active underground mining has received less attention as there are unique challenges that need to be overcome, especially if a procedure is to be applied daily in active mining. Unique challenges include preparation time, camera positioning, illumination and useability. The faces of active development drives are generally only available for a short period before prepared and blasted, thus information is lost if not mapped immediately. Furthermore, due to safety concerns, unsupported faces cannot be approached for physical mapping. SfM-MVS allows these faces to be viewed and mapped in the form of a virtual outcrop, thus, allowing for remote mapping of underground development, which at the Dugald River mine, located in Queensland, Australia, allowed for mapping continuity as staff worked remotely during COVID-19. This contribution describes how to set-up a capture in an underground mine to produce high-quality SfM-MVS 3D reconstructions of development faces. The methodology can be readily incorporated into a standard operating procedure. While the procedure can be used with most photogrammetry software packages that utilise SfM-MVS algorithms, it is best utilised using the provided Python script and Agisoft Metashape Professional v1.6. The script allows for automation of capture processing, which can free up several hours per day compared to user-interacted processing.