Σύγκριση μεθόδων

	Lead Isotope Provenance	NAA Provenance
Πεδίο	Αρχαιολογία	Αρχαιολογία
Οικογένεια	Process / pipeline	Process / pipeline
Έτος προέλευσης	2016	2003
Δημιουργός	Established in archaeometry through Oxford and other isotope laboratories from the 1960s onward	Michael D. Glascock & Hector Neff (MURR provenance program)
Τύπος	Isotopic provenance of metals, ores, and glazes by lead isotope ratios	Multi-element compositional sourcing of ceramics and obsidian via INAA and multivariate grouping
Θεμελιώδης πηγή	Renfrew, C., & Bahn, P. (2016). Archaeology: Theories, Methods, and Practice (7th ed.). Thames & Hudson. ISBN: 9780500292105	Glascock, M. D., & Neff, H. (2003). Neutron Activation Analysis and Provenance Research in Archaeology. Measurement Science and Technology, 14(9), 1516-1526.
Εναλλακτικές ονομασίες	Lead Isotope Analysis, Pb Isotope Provenance, Lead Isotope Sourcing, Metal Provenance by Lead Isotopes	Neutron Activation Provenance, INAA Compositional Sourcing, Compositional Group Analysis, Chemical Provenance by NAA
Συναφείς	2	2
Σύνοψη	Lead isotope provenance traces metals — copper, silver, lead, and lead-bearing glazes and pigments — back to the ore deposits from which they were extracted, by measuring the ratios of lead's four naturally occurring isotopes. Three of those isotopes (lead-206, -207, -208) are produced by the slow radioactive decay of uranium and thorium, while lead-204 is primordial, so the isotope ratios of an ore depend on the age and the original uranium, thorium, and lead content of the deposit. These ratios are fixed at the geological scale and are not altered by smelting, so they survive into the finished artifact. As Renfrew and Bahn note in their survey of provenance science, comparing an artifact's lead isotope signature to the isotopic fields of candidate ore deposits can identify, or at least constrain, the source of its metal. The method sits within the broader geoarchaeological toolkit of compositional and isotopic sourcing.	NAA provenance is the use of instrumental neutron activation analysis (INAA) to determine where archaeological ceramics, obsidian, and other materials were made or obtained, by exploiting their high-precision multi-element chemical fingerprints. INAA irradiates a sample with neutrons, making its elements briefly radioactive, and measures the characteristic gamma rays they emit to quantify the concentrations of roughly thirty elements, including many trace and rare-earth elements at very low levels. As Glascock and Neff describe in their account of the technique's role in archaeology, the analytical power of NAA lies less in the measurement itself than in what follows: the statistical formation of compositional groups and the assignment of artifacts to those groups and to geological or production sources. This entry focuses specifically on that provenance application — building compositional groups and attributing artifacts by Mahalanobis distance — rather than on the instrumental measurement in general.