Abrupt technological change at the 8.2 ky cal BP climatic event in Central Portugal. The Epipalaeolithic of Pena d’Água Rock-shelter

In central Portugal, the basic structures of the Pleistocene economy, technology and social organization patterns remain fairly similar until the 8.2 ky cal BP climatic event. Their impact has not yet been thoroughly analysed with regard to changes in lithic technology. The Epipaleolithic occupation of Pena d’Água Rock-shelter is dated to ca. 8.19 ky cal BP. In this paper we present a description of its lithic assemblage and put it in context with coeval and later sites of the Middle Tagus, highlighting the observed differences that pre- and post-date this event. Results indicate similarity in raw material acquisition strategies, mainly locally available quartzite cobbles for flake production. After the 8.2 ky event, chert becomes more common, allowing the systematic production of bladelet toolkits with high percentages of geometrics. Reorganized mobility patterns, from forager to logistic, may explain these changes, which remain stable until the Neolithic, ca. 7.4 ky cal BP.