Numerical Reconstruction of Paleolithic Fires in the Chauvet-Pont d’Arc Cave (Ardèche, France)

Abstract

The Chauvet-Pont d'Arc Cave (Ardèche, France), famous for its remarkable rock art, also contains unique thermal-alterations such as rock spalling and color changes on the walls. These alterations resulted from intense fires that have not been observed in the other decorated caves thus far discovered. The functions of these unusual fires challenge archaeologists. To characterize these combustions, we used a numerical tool, previously validated with experimental data, to study the thermo-alterations in the Megaceros Gallery. This unprecedented approach in cave art research enabled us to assess the wood quantities and locations of the hearths responsible for the thermoalterations. We report here that at least ten fires took place in the Megaceros Gallery while burning more than 170 kg of wood. Both simulation and in situ observations suggest that the branches were arranged in a tepee shape and purposefully positioned, some distance from the walls. This method therefore enables further analysis of the functions of these fires.

The conquest of the dark spaces: An experimental approach to lighting systems in Paleolithic caves

“…To solve this problem, and as a hypothesis based on the numerical data obtained after the simulation of the fires in the Chauvet Cave, it has been observed that large fires with high flames favor the expulsion of gases through convection currents, as well as develop an optimal thermal stratification to allow human occupancy in a cave during the operation of the fire. Because polluting gases are deposited in the upper area of the chamber above the flame, they leave a toxicity-free space that is large enough to be walked by humans and is slightly crouched [ 2 , 3 , 49 ]. Following this interpretation, in Nerja Cave, we have suggested using supports (for example, speleothems) to lift the flame and concentrate the smoke in the upper part of the cave, using a smaller volume of wood fuel than in the previous case [ 19 ].…”

“…These researchers detected through thermoluminic analysis of the heated walls and an experimental approach that the temperatures reached by the walls of Chauvet Cave (Ardèche, France), adjacent to the fires, were very high (> 300–375°C). In this sense, they propose that the purpose of these big fires could be related to functions additional to lighting, such as sanitation of the cavern, human protection from animals, smoke production without a direct practical need except in relation to the scenography of the decorated space, together with the voluntary modification of the coloration and consistency of the wall concerning the execution of Paleolithic art [ 21 , 22 , 49 ]. Likewise, they have developed some monitored experimental activities and numerical simulations of fires in caves [ 2 , 3 ].…”

“…Likewise, they have developed some monitored experimental activities and numerical simulations of fires in caves [ 2 , 3 ]. These results have been applied to the 3D geometry of Chauvet cave to better understand the functionality of these fires and Paleolithic underground activity [ 49 ]. In this cave, at least 10 fires were made by Paleolithic societies, using a total of 170 kg of fuel.…”

“…In this cave, at least 10 fires were made by Paleolithic societies, using a total of 170 kg of fuel. The smoke dispersion would allow the fires to be replaced given the thermal stratification of the gases [ 2 ], and the hearths would be arranged in a tepee shape nearby but slightly away from the wall to accomplish this [ 49 ]. These fires’ high radiation would be the main problem for human occupation when they were alight [ 3 ].…”

Water saturation variation in a fire-heated limestone gallery monitored by ERT

“…Notre-Dame of Paris, Deldicque & Rouzaud (2020)) or even natural caves (Carrancho et al 2009, Salmon et al 2019. Fires were ignited in a quarry situated in south-west France , Salmon et al 2020b), aiming at understanding the impact of Paleolithic fires on the Chauvet-Pont-d'Arc Cave walls (Ferrier et al 2017, Salmon et al 2020a.…”