The taphonomic characterization of a charcoal production platform. Contribution of an innovative pair of methods: Raman analysis and micromorphology

During the Industrial Revolution and until the 19th century, the fuel used in metallurgy was charcoal. The frequent charcoal-making places identified in European archaeological sites are one of the only direct markers of this activity. Understanding the soil stratigraphy of these locations enables us to characterize the intensity of charcoal production and especially to grasp an insight into the forest management of the studied site during charcoal making. Two types of soil profiles have been observed in Europe. The first presents one or several sterile horizons identifiable with the naked eye, separating charcoal levels. The second, which is the most commonly observed type at European archaeological sites, is characterized by a single charcoal level of variable thickness. For the present study, located in eastern France (Franche-Comté), we propose to characterize the soil profile of a charcoal platform, which looks like the second type observed at the European scale, through the application of an innovative pair of methods: The Raman analysis and micromorphology. The Raman paleothermometer, defined by Deldicque et at. (2016) was adapted to define the temperatures reached in charcoal-making contexts. These measurements agree with the literature and experiments. These temperatures are regularly distributed over the profile, confirming the reuse of the platform. Similarly, the micromorphology of the soil profile reveals clear indicators of reuse, with no evidence of long interruptions in charcoal making.