Dating Late Pleistocene Archaeological sites in the Americas

Summary

This is an abstract from the "Geoarchaeology in First Americans Research, Part 1" session, at the 90th annual meeting of the Society for American Archaeology.

Geoarchaeological studies are critical to the evaluation of late Pleistocene archaeological sites in the Americas. One of geoarchaeology’s important contributions is to provide an accurate age for a site and its associated stratigraphy. Today, I will discuss best practices for the radiocarbon dating of bone. Laboratories currently use different chemical protocols to extract datable material from bone. These different chemical fractions all yield ages, but most are not accurate. Because atomic accelerators can produce accurate and precise measurements on small samples, it allows us to date chemical fractions derived from bone collagen that originated only from the bone itself, effectively removing all contamination. Currently, only XAD-resin purified collagen or specific amino-acid (hydroxyproline) extractions consistently yield accurate ages. Other chemical fractions provide ages that are not consistently accurate. Accurate dating is critical to establishing when the first people arrived in the Americas, how they dispersed across the Americas, determining the timing of extinction of megafauna at the end of the Pleistocene, and other important questions. Without accurate chronology our understanding of the process of the peopling of the Americas will take many unnecessary detours to dead ends.

This Resource is Part of the Following Collections

• Geoarchaeology in First Americans Research, Part 1   •
• Society for American Archaeology 90th Annual Meeting, Denver, CO (2025)

Keywords

Record Identifiers

Abstract Id(s): 50415