Determinação volumétrica em mineração de calcário utilizando aerofotogrametria e modelagem digital do terreno

Abstract

Accurate volume determination in mining is essential for production planning and management. In this context, UAV-based aerophotogrammetry emerges as an efficient alternative to conventional methods, delivering gains in precision, safety and agility. This study aimed to apply aerophotogrammetry to estimate the available limestone volume in a 91-hectare open-pit operation in the state of Mato Grosso, Brazil. The workflow comprised four main stages: flight planning, aerial image acquisition, photogrammetric processing in Agisoft Metashape and volumetric calculation in the topographic software DataGeosis. Mapping was carried out with a multirotor drone equipped with a 20 MP camera, using six RTK-GNSS ground control points to ensure centimetre-level georeferencing. Processing generated a dense point cloud, digital terrain model and vegetation-free orthomosaic, which were then imported into DataGeosis for bench modelling. The analysis indicated an extractable volume of 3.176 million m³, equivalent to 7.623 million t assuming an average density of 2.4 t m⁻³. The method enabled precise mine planning and volume reconciliation, reduced field time, minimised occupational hazards, and allowed frequent monitoring of stockpiles, working faces and slopes. It is concluded that integrating drones, photogrammetric processing and digital modelling constitutes a strategic tool for limestone-mining operations, supporting agile, accurate and sustainable decision-making throughout the production cycle.