Integrated Mining Tunnel Survey
LandScope have successfully completed a large scale integrated UAV aerial photography, laser scanning and photogrammetry survey of 25 mining tunnels forming part of an old remote mining site in the Georgia mountains.
GNSS was used to coordinate the UAV ground control and photogrammetry targets, required to georeference the final data sets.
Due to the vertical nature of the surrounding rock formations at the tunnel entrances influencing GNSS precision, the survey team made use of photogrammetry techniques to capture sufficient surrounding data resulting in the production of georeferenced point clouds of the tunnel entrances (see Figure 3 below).
The internal point cloud data from the tunnel, collected using the Zeb Revo, was merged with the photogrammetry outputs providing a complete georeferenced 3D representation of the tunnels once overlaid on the UAV digital ground model (see Figure 2 below).
National survey control was not present in the area therefore requiring a primary survey control network to be established, referenced to UTM38N ITFR2008 with elevations derived using the EGM08 1” geoid model.