Mining under the canopy: Unveiling the archaeo-mining record in the Colline Metallifere with LiDAR analysis and multidisciplinary studies

Abstract

The study of ancient disused mining contexts in the Mediterranean region is particularly challenging due to the impact of modern reclamation works and the presence of dense vegetation, which impede the application of conventional archaeological research methods.Pivoting on the multidisciplinary approach driven by the ERC nEU-Med project to the study of historical landscapes, and thanks to a new LiDAR survey promoted by the project in 2019, new investigations were carried out in ancient and modern mining contexts in the territory of Colline Metallifere (southern Tuscany, Italy). The district is renowned for its important metal deposits characterized by copper, lead, zinc and silver vein bodies that have been mined since the Bronze Age, with a particularly intense phase of exploitation during the Medieval period. The primary objective of the LiDAR DTM analysis was to map features and delineate the characteristics of the archaeo-mining landscape in five densely vegetated contexts. The analysis revealed numerous novel evidence related to mining activities (574 within the five territorial samples analyzed in this contribution), of which 72% were also inspected through fieldwalking surveys. These features have been interpreted by means of archaeological surveys, documentary research and statistical and spatial analysis. A particular focus was placed on the study of the most prevalent type of feature, which is the mining shaft. The development of reliable parameters of interpretation, including the dimensional aspects of each individual mining shaft (area, diameter and depth of the basin), the distances between shafts, and presence or absence of dumps, played a crucial role in disentangling the complex topography of the mining sites. The favourable results achieved through this study will enable the application of the method on a larger scale to other nearby mining contexts, overcoming the constraints of accessibility and visibility that have so far significantly influenced the analysis of mining territories.