SESSION 2 – Ancient lithic trade and economics
Upper Palaeolithic social networks in Central and Northern Portugal as revealed by lithic raw material sourcing

Raw material sourcing is an effective way to reconstruct foraging strategies and the ranges involved in resource exploitation. Our aim is to infer spatial relationships between different geographical areas as well as to define ranges and networks, by identifying lithic raw material sources and technological modes of transformation and use.

We present the results of a study on flint, silcrete and filonian quartz sources used in Upper Palaeolithic occupations preserved in rock-shelters and open-air sites from two radically different geological units. Central Portuguese sites are located in the Western Iberia margin Meso-Caenozoic deposits (Estremadura Massif, Sicó Massif, Outil or Cantanhede Plateau), where several sources of flint and other siliceous rocks are easily available. The second group is composed of Northern Portuguese sites on the Iberian Hercynian crystalline basement (Côa Valley), with locally restricted fine grain filonian quartz sources and no available flint or silcrete. Both groups are compared with a third group located at the limit of the two regions, where both resource raw material types are regionally available (Lower Vouga Valley). We use the lithic supply network, defined by a GIS least-cost algorithm, as a proxy for social and territoriality reconstruction, defining a network between the Portuguese Estremadura and the Central Northern Meseta.