Applications of elemental analysis for archaeometric studies : analytical and statistical methods for understanding geochemical trends in ceramics, ochre and obsidian

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on August 7, 2007)Vita.Thesis (Ph. D.) University of Missouri-Columbia 2006.Three areas are covered in this dissertation: elemental analysis of Caborn-Welborn ceramics, elemental analysis and geochemical characterization of ochres, and construction and implementation of a portable XRF instrument for artifact analysis.The first study is analysis of ceramics from Caborn-Welborn (Ohio Valley) archaeological sites, using both instrumental neutron activation analysis (INAA) and particle-induced X-ray emission (PIXE). By using principal components analysis and posterior discriminant analysis, it was possible to compositionally distinguish lower Ohio Valley ceramics in both extra-regional and local analyses. The second study analyzes iron oxides (ochre) from several sources using instrumental trace analysis techniques, including INAA, and X-ray fluorescence spectrometry (XRF). Multivariate statistics of the data point to trends in the inter- and intra-source variability of ochre. Elemental results from Missouri, California, Oregon, Texas, Arizona, and Peru have been investigated. These trends in geochemistry lead to a better understanding of ancient ochre procurement. The third study covers the set-up, design and system geometry calculations, testing, and calibration of a portable XRF system. The system was transported to and used successfully in southern Peru in August 2005 to characterize obsidian artifacts.Includes bibliographical reference

Microbial composition analyses by 16S rRNA sequencing: A proof of concept approach to provenance determination of archaeological ochre

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Many archaeological science studies use the concept of “provenance”, where the origins of cultural material can be determined through physical or chemical properties that relate back to the origins of the material. Recent studies using DNA profiling of bacteria have been used for the forensic determination of soils, towards determination of geographic origin. This manuscript presents a novel approach to the provenance of archaeological minerals and related materials through the use of 16S rRNA sequencing analysis of microbial DNA. Through the microbial DNA characterization from ochre and multivariate statistics, we have demonstrated the clear discrimination between four distinct Australian cultural ochre sites

Comparison of ochre samples.

<p>NMDS ordination derived from a Bray-Curtis similarity matrix calculated from the square-root transformed abundance of 16S rRNA sequences matching the Greengenes database (13_08), order level.</p

Comparison of the ochre samples.

<p>CAP analysis (using m = 4 principal coordinate axes) is derived from the sum of squared canonical correlations of 16S rRNA sequences matching the Greengenes database (13_08), order level.</p

Results of CAP analysis (using m = 6 principal coordinate axes, explaining 99.8% of the total variation) testing the hypothesis that taxonomic composition differs for order level classifications associated with different ochre samples.

<p>Results of CAP analysis (using m = 6 principal coordinate axes, explaining 99.8% of the total variation) testing the hypothesis that taxonomic composition differs for order level classifications associated with different ochre samples.</p

Map indicating the geographic locations of the sources sampled in this study.

<p>Modified from <a target="_blank">http://d-maps.com/carte.php?num_car=3289&lang=en</a>.</p

Results of CAP analysis (using m = 1 principal coordinate axes, explaining 100% of the total variation) testing the hypothesis that elemental composition differ for each ochre sample.

<p>Results of CAP analysis (using m = 1 principal coordinate axes, explaining 100% of the total variation) testing the hypothesis that elemental composition differ for each ochre sample.</p

Phase Analysis of Australian Uranium Ore Concentrates Determined by Variable Temperature Synchrotron Powder X-ray Diffraction

The chemical speciation of uranium oxides is sensitive to the provenance of the samples and their storage conditions. Here, we use diffraction methods to characterize the phases found in three aged (>10 years) uranium ore concentrates of different origins as well as in situ analysis of the thermally induced structural transitions of these materials. The structures of the crystalline phases found in the three samples have been refined, using high-resolution synchrotron X-ray diffraction data. Rietveld analysis of the samples from the Olympic Dam and Ranger uranium mines has revealed the presence of crystalline α-UO2(OH)2, together with metaschoepite (UO2)4O(OH)6·5H2O, in the aged U3O8 samples, and it is speculated that this forms as a consequence of the corrosion of U3O8 in the presence of metaschoepite. The third sample, from the Beverley uranium mine, contains the peroxide [UO2(η2-O2)(H2O)2] (metastudtite) together with α-UO2(OH)2 and metaschoepite. A core–shell model is proposed to account for the broadening of the diffraction peaks of the U3O8 evident in the samples