Historical underground quarrying: A multidisciplinary research in the Caumont quarry (c. 13th–19th centuries), France

Abstract

Quarries represent ‘landscapes archives’ as they supplied the stone required for historical buildings. Among them, the Caumont ancient quarry stands out in northern France, with its huge dimensions and its historical role, providing building stones at a regional scale since at least the Middle Ages. The present study aims to approach the quarrying methods used over time in Caumont by means of an optimized methodological approach. The designed methodology combines (1) the 3D modelling of the quarry, (2) archaeological prospection, (3) stratigraphical and microscopical study of the quarried bedrock, and (4) the geochronological approach in stalagmites precipitated inside the quarry. The studied quarry of Caumont was excavated as an open-cast quarry beginning with the escarpments along the River Seine and transformed later to an underground quarry supported by contoured bedrock pillars. The underground quarry with its 12 km of galleries shows a chambers-and-pillars pattern style excavated using two methods, producing an inferred volume of 273,529 m3 of building stone. The U–Th dating of two stalagmites suggests that quarrying activity had begun since at least the early medieval period and agrees with the excavation techniques and historical documents.