Going with the Flow: The Impact of Holocene Fissure Eruptions on Obsidian Source Use in Southeastern Idaho
A chemical analysis of diagnostic projectile points from the Craters of the Moon National Monument and Preserve in southern Idaho suggests that direct procurement of raw material from local obsidian sources was a long-term pattern in the region. However, significant trends in the frequency of specific sources associated with particular projectile point types were noted in this study. Statistical tests suggest that these trends are linked with atlatl versus bow and arrow technology. Although changes in mobility or population movements could have influenced this pattern of distribution, a more reasonable explanation for fluctuations in the frequency of particular sources suggests that they may be due to barriers created by Holocene lava flows that coincidentally prevented access during specific time periods.