Gavrinis, The raising of digital stones

International audienceThe Tumulus of Gavrinis, which is located in Brittany, is one of the best known monuments of Neolithic art because of its extraordinary engravings. A joint team of archaeologists and architects began recording the monument using digital multiscalar technology in 2011. The scanning was complicated by the narrowness of the inner spaces, uncomfortable conditions, granulometry of the stone, and extensive vegetation coverage. A huge database was created by using a combination of photogrammetric technology and low-tech scanning methods. A lot of post-production work was needed to turn the cloud of data into a clean 3D model, since the original tumulus is irregular and lacks any repetitive patterns or predictive geometry. The goal was to obtain a detailed geometric analysis of the tumulus in order to develop a better understanding of its architecture and engravings, which are sometimes less than a millimeter deep.This article covers the technological solutions that we applied while confronting situations ranging from the need to enhance a carved figure to our effort to reconstruct the entire monument by collating the results of several different recording techniques