Changes and continuities in the lithic archaeological record of the Upper Santa Cruz River basin (Patagonia, Argentina) between the Middle and Late Holocene.

FRANCO, NORA VIVIANA; VETRISANO, LUCAS

Burgos

Congreso; XVII World UISPP Congress; 2014

International Union for Prehistoric and Protohistoric Sciences (UISPP)

The Santa Cruz river originates in the Andean mountains and has its mouth in the Atlantic Ocean. Human circulation is limited to the west, where the southern Ice Field is located. The area comprises lowlands and highlands with Nothofagus forest to the west and steppe to the east. The highlands have passes which allow human movement to the Pacific coast. The climate is wet to the west and more arid to the east. Paleoclimatic studies have shown the existence of more arid and wetter periods in the past. There is also evidence of rock fall-off and ashes coming from volcanic eruptions, which would have affected human life. The first evidence of human utilization of the upper Santa Cruz river basin dates to the early Holocene, and comes from Chorrillo Malo 2 rock shelter, located south of it. The use of the area seems to have been discontinuous until ca. 4,300 14C yr BP when, according to technological and raw material information, both lowlands and highlands have been integrated within the home range of the same cultural group. Between ca. 3,800 and 3,600 14C yr BP, the same cultural group buried their dead at the same rock shelter. A similar kind of burials was identified at similar ages at spaces located between 150 and 250 km to the south, supporting the idea of regular social ties between human groups using these spaces. The purpose of this paper is to analyze the existence of technological continuities and changes in the lithic archaeological record recovered from two rock shelters (Chorrillo Malo 2 and Río Bote 1) located in the lowlands, south of the Santa Cruz river basin. There is a distance of ca. 60 km between the two sites. Here we will concentrate on strata dated between ca.6000 to 2800 14C yr BP. Analysis will focus on cores, flakes and tools which can provide information on the technology involved. Raw material availability will be taken into account in order to understand lithic variability during this time period. Although the two sites could have had different through time, in both of them Levallois technology was identified between ca. 4,300 and 3,600 14C yr BP. This technology is also present at the Pacific slope of the highlands by ca. 4,500 14C yr BP. Previous deposits show the presence of blades, although no evidence of core preparation has been recovered until the moment. Results obtained are useful to understand the process of incorporation of a new technology -which implies additional effort and time in core preparation- into the area and the integration of these spaces within the home range of a single cultural group.