Late Pleistocene and Early Holocene Obsidian in Alberta and Human Dispersal into North America’s Ice-Free Corridor

ABSTRACT We utilize pXRF to source the oldest obsidian artifacts in Alberta, Canada. The province lacks obsidian outcrops and hosts much of the late Pleistocene Ice-Free Corridor, the northern and southern ends of which are in proximity to obsidian outcrops in Yukon, Alaska, Idaho, and Wyoming. The early presence of these obsidians in Alberta informs models of human dispersion. Results point to an early establishment of relationships in the central Ice-Free Corridor that reached into Oregon, Idaho, and Alaska. Alberta appears to have been entered by people from the south who had ties to the Pacific Northwest and Intermountain West. After biotic viability of a full Corridor, limited evidence suggests that northern people from Beringia may have trickled south and admixed with southern populations in the central Corridor region. Upon deglaciation of access routes through the Rocky Mountains, obsidian from western sources in British Columbia arrived relatively quickly in northern Alberta.