The use of unmanned aircraft system technology for highwall mapping at Isibonelo Colliery, South Africa

understanding of the structure of any mineral deposit. Several mapping methods may be applied depending on the available exposure/outcrop and nature of the orebody; for example, coal deposits typically suboutcrop only, therefore an opencut highwall provides the best exposure for mapping the geology. Mapped information, when incorporated into a resource model (generated from exploration borehole data), improves the understanding of the orebody or coal seam. This research paper focused on the use of unmanned aircraft system (UAS) technology for pit highwall mapping to generate data for updating geological models and avail the latest information to mine planning to improve the short-term plans. The Isibonelo Colliery’s geological model is updated annually and is termed a resource geological model, from which the mining model is built. This research was motivated by the absence of a short-term geological model that could be used for short-term mine planning. Short-term models are built by mine geologists, when they take the latest release of the resource geological model and add in data as it becomes available from progressive mining. The data includes surveyed highwall seam-roof and/or seam-floor contacts, faults, dykes, blast-hole data, grade control hole data, and any other measurements deemed necessary for modelling. Highwall mapping with a survey total station is standard practice at Isibonelo Colliery. Recent technological advances have made new digital photogrammetry techniques available for mapping, with a camera being carried by a UAS which does highwall mapping. The process of short-term geological modelling allows for the incorporation of small-scale features, such as seam rolls and previously unidentified faults, which may not be obvious from broadly spaced exploration drill-hole data.