Spatiotemporal patterns of obsidian exploitation in the later prehistory of eastern Kamchatka Peninsula (Russian Far East)

Obsidian artefacts from archaeological sites in two regions of Kamchatka Peninsula were analysed by the XRF method (66 samples). The chronology of the cultural complexes was established by radiocarbon dating and the tephra layers as markers. The Least Cost Path (LCP) method was used to understand better the scale of obsidian exchange and the complexity of its transportation. It was found that obsidian from six primary sources was exploited by ancient sedentary natives of Kamchatka. The largest share (49.2 %) belongs to the KAM-7 source (Belogolovaya River, part of the Ichinsky cluster). The content of obsidian from other sources is 30.8 % for KAM-1, 9.2 % for KAM-3 (Itkavayam Volcano), 6.2 % for KAM-4, 3.1 % for KAM-2, and 1.5 % for KAM-5 (Payalpan Volcano). For cultural layers older than ca. 1650 BP, obsidian from all six sources was used; for cultural strata younger than ca. 1650 BP, four sources are identified. At the sites dated to the sixteenth − seventeenth centuries AD, obsidian from two sources was exploited. Based on the current and previous analyses of the provenance of obsidian artefacts, it is established that large-scale exchange networks existed on Kamchatka since the late Upper Palaeolithic (ca. 17,500–11,500 cal BP) to later prehistory (ca. 6800–400 cal BP), and finally until European contact. The results of LCP modelling demonstrate that obsidian was transported over a distances of up to ca. 300–400 km, and in some cases up to ca. 600 km, mainly by river valleys.