Combining terrestrial stereophotogrammetry, DGPS and GIS-based 3D voxel modelling in the volumetric recording of archaeological features

Archaeological recording of structures and excavations in high mountain areas is greatly hindered by the scarce availability of both space, to transport material, and time. The Madriu-Perafita-Claror, InterAmbAr and PCR Mont Lozère high mountain projects have documented hundreds of archaeological structures and carried out many archaeological excavations. These projects required the development of a technique which could record both structures and the process of an archaeological excavation in a fast and reliable manner.The combination of DGPS, close-range terrestrial stereophotogrammetry and voxel based GIS modelling offered a perfect solution since it helped in developing a strategy which would obtain all the required data on-site fast and with a high degree of precision. These data are treated off-site to obtain georeferenced orthoimages covering both the structures and the excavation process from which site and excavation plans can be created. The proposed workflow outputs also include digital surface models and volumetric models of the excavated areas from which topography and archaeological profiles were obtained by voxel-based GIS procedures. In this way, all the graphic recording required by standard archaeological practices was met.