Elemental mapping of micromorphological block samples using portable X‐ray fluorescence spectrometry (pXRF): Integrating a geochemical line of evidence

Archaeological soil and sediment micromorphology represent the most efficient way to obtain microcontextual information at archaeological sites. Because of the generally qualitative (descriptive) nature of micromorphology, one difficulty with the method is establishing vertical and lateral continuity of the observed layers or features. Through an Exploratory Spatial Data Analysis approach, we demonstrate that portable X‐ray fluorescence (pXRF) elemental mapping of resin‐impregnated micromorphological block samples provides a complementary geoarchaeological approach for gathering valuable chemical information at the mesoscale. Specifically, we integrate these data with micromorphological analyses to aid our interpretation of the formation of a complex Archaic (seventh century) ritual ash midden (eschara) from the site of Kalapodi, in Greece. We demonstrate that pXRF elemental mapping provides a rapid and cost‐effective approach to generate a geochemical line of evidence during micromorphological analyses, and can help tease apart and interpret complex formation processes, such as those found in anthropogenic deposits.

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