Chert sourcing using LIBS: applications to the case of Cova del Parco (Alòs de Balaguer, La Noguera, Spain)
Résumé
Lithic materials are the most commonly found artefacts on Palaeolithic archaeological sites and Cova del Parco (Alòs de Balaguer, La Noguera, Spain) is not an exception. There, cherts originating from carbonate lacustrine environments were widely exploited by Upper Palaeolithic hunter gatherers populations, and in a similar way, this type of chert was also predominant in the archaeological set of different sites chronologically related to Cova del Parco from the south of the Pyrennees. Archaeo-petrographic sourcing studies have identified different potential sources placed in the first Pre-Pyrenean foothills and the middle Ebro Basin, but these approaches were unable to distinguish between sources.
With the aim of analyzing large archaeological corpus, including museum collections, we conducted a pilot experimentation of the use Laser Induced Breakdown Spectroscopy (LIBS) for chert geochemical sourcing. This portable instrument allows fast, scalable, micro-destructive analysis, and has rarely been used for chert sourcing, with only a few exploratory applications.
In this communication we will present the use of LIBS for chert sourcing, as well as an application using supervised classification models on LIBS spectra for determining the provenance of lacustrine cherts. allowing successful discrimination of lacustrine geological sources and providing predictions for the origin of a selection of chert artifacts recovered at the Middle Magdalenian level from Cova del Parco.