Identification of activity areas by multi-element characterization of sediments from modern and archaeological house floors using inductively coupled plasma-atomic emission spectroscopy

A pilot study on the chemical analysis of earthen house floors, using both modern and archaeological localities, was undertaken to determine the degree to which activities leave detectable chemical residues, and whether these residues are preserved in archaeological contexts. The goals were to develop techniques for the identification and interpretation of activity areas in archaeological structures and to determine which elements serve to distinguish activities. One modern structure from Oaxaca, Mexico and two archaeological house floors (ii-om British Columbia, Canada and Oaxaca, Mexico) were studied. Soil samples were collected from floors at all three sites and analysed by inductively coupled plasma-atomic emission spectroscopy (ICP/AES) for Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, Sr, Ti, and Zn. Preliminary results show that activity areas in the modern house compound can readily be distinguished on the basis of chemical residues in soils, that archaeological features are chemically distinct from natural soils, and that features such as floors, and hearths can be distinguished from each other and from the natural prehistoric ground surface. Multi-element characterization by ICP/AES offers an advantage over traditional, single element analysis by yielding more useful data for less effort, expense, and time.