Use of muon imaging for enhanced reconstruction of underground cavities and associated stability conditions at a historical mining site

This paper investigates the use of muon imaging technique (muography) to enhance engineering geological surveys, integrated with advanced geomatic methods like LiDAR systems and UAV-based digital photogrammetry, for detecting and characterizing cavities in an historical and partially abandoned mining site. The case study focuses on the Temperino mine, located within the Archaeological and Mining Park of San Silvestro, Italy. Historically significant, the site was mined for skarn minerals from the Etruscan period until the 20th century and the rock mass contains a complex network of both man-made and natural voids. These cavities pose significant risks to rock mass stability, including roof collapses, sidewall spalling and surface subsidence. In this study, transmission-based muography data collected using a muon tracker inside the mine were combined with terrestrial and mobile laser scanning (TLS and MLS), UAV-based photogrammetry, and geological modeling to reconstruct the geometry of cavities and surrounding rock mass. This integrated approach enables to achieve a preliminary numerical model of stress and strain distributions to assess stability conditions. By addressing the challenges associated with cavity detection and stability analysis, this study highlights the potential of muography to complement traditional engineering geological survey methods and the importance of a multidisciplinary approach to enhance safety, resource management and the sustainable revitalization of historic and abandoned mining districts.