Reduction Strategies and Geochemical Characterization of Lithic Assemblages: A Comparison of Three Case Studies from Western North America

Abstract

Based on a simple model of lithic procurement, reduction, and use, we generate predictions for patterns in source diversity and average distance-to-source measurements for flaked stone assemblages left behind by small-scale and residentially mobile populations. We apply this model to geochemical data from obsidian artifacts from three regions in western North America. As predicted, results show markedly different patterns in the geochemical composition of small flakes, large flakes, and formal tools. While small flakes and tools tend to have greater source diversity and are on average farther from their original source, the large flake assemblage is composed of fewer and closer sources. These results suggest that a failure to include very late stage reduction (e.g., pressure flakes) and microdebitage in characterization studies may bias interpretations about the extent of residential mobility and/or trade patterns because more distant sources will be underrepresented.

The Analysis of Stone Tool Procurement, Production, and Maintenance

“…This analysis is proving to be quite promising. Others have used debitage sizes to help determine aboriginal land-use practices (Baumler and Davis 2004;Eerkens et al 2007). Inferences derived from debitage are often made from a population or assemblage of debitage specimens.…”

“…Obsidian sources have been widely assessed geochemically and have proven to be fairly reliably linked to archaeological specimens (Bayman and Shackley 1999;Eerkens and Glascock 2000;Eerkens et al 2007;Ferguson and Skinner 2005;Glascock et al 1994;Hughes 1998;Negash et al 2006Negash et al , 2007Roth 2000;Shackley 1998bShackley , 2005Stoltman and Hughes 2004;Tykot 2002Tykot , 2003. Some obsidian provenience studies have been able to reliably recognize ''subsources'' of obsidian and have shown that these sources provide useful information related to human land-use practices (Eerkens and Rosenthal 2004;Young 2002).…”

Using ichnofossils to characterize chert tools: A preliminary study from Southern Iberia

“…In the case of chert, characterization can be approached on the basis of different visual macrogeological features (i.e., color, aspect, transparency, fracture, presence of inclusions, etc.). This visual approach has thus far proven insufficient, however, and in recent years additional criteria have been applied to characterize siliceous rocks including sedimentary petrography (Séronie-Vivien & Séronie-Vivien, 1987;Delange, 2003;Odell, 2004) and geochemical analysis (McDonnell, Kars, & Jansen, 1997;Malyk-Selivanova et al, 1998;Bressy, 2003;Eerkens et al, 2007;Milne, Hamilton, & Fayek, 2009). Unfortunately, most of these methodologies entail a major disadvantage: the partial destruction of the archaeological piece.…”

Combining visual and geochemical analyses to source chert on Southern Baffin Island, Arctic Canada

“…From this we can learn about the formation and depositional contexts of various lithic raw materials so as to begin to define specific source areas (Leudtke, 1992:39). The use of geochemical and mineralogical approaches to characterize the elemental and mineralogical composition of lithic materials has gained momentum in archaeology over the last several decades (e.g., Eerkens et al, 2007;Evans et al, 2007;Hull et al, 2008;Hess, 1996;Hoard et al, 1992Hoard et al, , 1993Jarvis, 1988;Leudtke, 1978Leudtke, , 1979Morrow et al, 1992;Malyk-Selivanova et al, 1998;Norman et al, 1989;Speilbauer, 1984). Those approaches most commonly used in chert sourcing studies are X-ray fluorescence (XRF), X-ray diffraction (XRD), instrumental neutron activation analysis (INAA), and inductively coupled plasma (ICP).…”

“…Therefore, both SIMS and LA-ICP-MS are minimally destructive since they require very small samples (ϳ1 mm). [XRF is also relatively nondestructive; however, it is a bulk analytical technique (Eerkens et al, 2007).] Finally, unlike INAA, SIMS samples do not require any special post-analysis curation since they are not rendered radioactive upon completion of their study (Church, 1994:51).…”