El tecno-complejo del Embalse de Urrúnaga (Álava). Nuevas aportaciones al conocimiento de las sociedades del Paleolítico inferior en el norte de la Península Ibérica

This paper presents a new Lower Palaeolithic lithic assemblage recovered from the Urrunaga reservoir (Alava, Basque Country, Spain). The collection consists of 70 artefacts, which have been analysed according to the petrological, modal-morphological (retouching structures), technological and metrical structures following the Analytical Typology approach. Even small by artefact number, this assemblage can contribute, through a comprehensive and interdisciplinary methodology, to a better understanding of raw material acquisition dynamics, as well as knapping and retouching techniques carried out by Lower Palaeolithic societies. Concerning the raw material acquisition, the massive use of shale suggests the dominance of local procurement patterns. However, the systematic use of distinct siliceous cemented shale reflects selective strategies for alluvial deposits. We propose, that this selection is based on two raw material criteria: knapping properties, derived from the fine and homogenous grain-size and the hardness due to its silica cement composition. The further procession of this pebbles suggests two different techniques. The first one describes an uni- and bifacial exploitation, producing side scrapers, scrapers and denticulates. The second one is based on centripetal cores. Blanks and cores were also modified, using similar retouching techniques as for the artefacts directly made on pebbles. The metrical dataset derived from this analysis shows that artefacts on pebbles and cores have similar dimensions, nevertheless, retouched and non-retouched flakes have irregular size distribution. This lithic techno-complex provides new information about Lower Palaeolithic groups within a region, where the archaeological evidences for this period are scarce. In addition, this paper highlights the importance of this reservoir area, located as a mandatory crossroad between the North-Iberian plateau, the Ebro valley and the Cantabrian coastal region.