California obsidian

We collected sets of single-shot broadband LIBS spectra in the Army Research LIBS Laboratory for 27 obsidian samples from major sites across the CVF as well as for samples from 4 other California obsidian locations - Bodie Hills, Mt. Hicks, Fish Springs, and Shoshone. The resultant obsidian LIBS spectral database was analyzed by multivariate statistical analysis. 

Although all obsidian samples exhibited quite similar broadband LIBS spectra, the PLS-DA approach was able to clearly discriminate samples from the 5 different California obsidian locations. Within CVF, it is possible to distinguish the five subgroupings defined on the basis of ICP-MS... 

Table 1. Confusion matrix for the PLS-DA analysis of the California obsidian localities using 600 broadband LIBS spectra and 15 latent variables to produce 5 model classes. Horizontal lines separate the groupings for the Coso Volcanic Field by Draucker (2007) and the other four California obsidian localities...

Stevenson, C. M., M. Goitesnian, and M. Macko (2000), Redefining the working assumptions of obsidian hydration dating, /. California and Great Basin Anthropology 22, 223-226. 

The Coso Volcanic Field (CVF) in California, USA (Fig. 1) contains at least 38 high-silica rhyolite domes (Duffield Bacon 1981), many of which contain obsidian glass that has been quarried for tools by the indigenous population for more than 12,000 years. CVF obsidian... 

Eerkens, J.W. and Rosenthal, J.S. (2004). Are obsidian subsources meaningful units of analysis temporal and spatial patterning of subsources in the Coso Volcanic Field, southeastern California. Journal of Archaeological Science 31 21-29. 

Hughes, R.E. (1994). Intrasource chemical variability of artefact-quality obsidians from the Casa Diablo area, California. Journal of Archaeological Science 21 263-271. 

Jack, R.N. (1976). Prehistoric obsidian in California. I. Geochemical aspects. In Advances in Obsidian Glass Studies, ed. Taylor, R.E., Noyes Press, Park Ridge, New Jersey, pp. 183-217. 

The three silicates obtained from Wards Scientific Establishment and employed in this study are obsidian from St. Helena, California, microline from Ontario, Canada and albite from South Dakota. The bulk of the samples were crushed and sieved to between 211 and 423 (im. Fines were removed by repeated ultrasonic cleaning and decantation. Measured BET... 

Shackley, S. M. Eklund, E. Ogasawara, C. Report Source Provenance of Obsidian Artifacts Jiskairumoko (189), Peru University of California Berkeley Archaeological XRF Laboratory Department of Anthropology, Berkeley, CA May 2004 p 10. 

Hughes, R. E. Diachronic Variability in Obsidian Procurement in Northeastern California and South Central Oregon University of California Press Berkeley 1986. 

Fiber and particulate residues, archaeological textiles by infrared techniques, 44-77 Fiber charring, 49-50 Fiber dyeing, 51 Fiber mineralization, 51 Field analysis by XRF, obsidian sources in Central Pet6n, Guatemala, 506-521 Fish Slough Cave, Owen s Valley, California, population movement studies, 80... 

Pattern recognition is a powerful tool in the identification of archaeological artefacts. A typical example of a pattern recognition application in chemistry is the classification of obsidian artefacts by Kowalski et. al. C1623. A total of 45 obsidian samples from different sources in northern California and 27 archaeological obsidian artefacts of unknown origin were analyzed by X-ray fluorescence spectroscopy. 

Investigations of prehistoric mobihty strategies in California based on obsidian analysis... 

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