Measurement in Network-RTK for the Survey And Representation of A Quarry: Potentials And Limits

The survey of quarries by geomatics techniques represents an important activity for the monitoring and protection of the landscape. In general, there are several techniques for monitoring a quarry, such as ALS (Airborne Laser Scanning), traditional airborne or UAV (Unmanned Aerial Vehicle) photogrammetry, total station or GNSS (Global Navigation Satellite System). In this paper, a survey of a quarry using the GNSS (Global Navigation Satellite System) and Network Real-Time Kinematic (NRTK) method shows the simplicity, cost-effectiveness and potential of this approach. This approach allowed obtaining accuracy in real-time of a few centimetres; moreover, thanks to specific functions implemented in the GNSS receiver, it was possible to determine, with high accuracy, the position of inaccessible points or points where it was not possible to obtain a good geometric receiver-satellite configuration. High accuracy in positioning leads to benefits in estimating the extracted volumes in a quarry's 4D monitoring activity and is useful for environmental and civil engineering design activities. The paper shows the validity of the NRTK method by the analysis of a case study of a quarry of about 8 hectares located in Italy.