Re-enacting the sequence: combined digital methods to study a prehistoric cave

This contribution seeks to demonstrate how recently developed 3D GIS platforms can help archeologists in relating to the original context legacy data that can be employed to digitally reconstruct the sequence of arbitrary layers as it was observed and then excavated in the end of the nineteenth century. This research has been conducted on the prehistoric cave of Stora Förvar, located on the small island of Stora Karlsö, in South-Eastern Sweden. As a part of a research project titled “The pioneer settlements of Gotland,” this line of enquiry has sought to combine 3D-based digital acquisition techniques, Geographical Information Systems (GIS), and old archival material (hand-made drawings, artifacts lists, historical pictures) in order to virtually reconstruct the original sequence as it was excavated through the method of arbitrary layers. At a later stage, the reconstructed sequence has been employed to re-contextualize and analyze the distribution of artifacts so as to detect any possible pattern that could have been useful for defining the chronological boundaries of the Mesolithic phase of habitation of the cave. In brief, three main objectives can be defined: (a) to re-create a spatial connection between the artifacts retrieved at the time of the excavation and the sequence of layers, (b) to define density maps showing the relationship between volumes of layers and categories of artifacts belonging to the sequence, and (c) to further our knowledge about the Mesolithic habitation of the cave, not only vertically (chronologically) but also horizontally.