GEOCHEMICAL IDENTIFICATION OF FEATURE FUNCTION AND ACTIVITY AREAS AT A LATE PALEOINDIAN THROUGH MIDDLE ARCHAIC ARCHAEOLOGICAL SITE: DUST CAVE, ALABAMA

The geochemical analysis of archeological sediments, initially limited to single element studies (e.g., phosphorus) to identify archaeological sites, has expanded to multi-element investigations with the goal of identifying and interpreting activity areas within sites. The present study examines the function of features and activity areas occurring at Dust Cave, a limestone cavern in northwestern Alabama occupied during the Late Paleoindian through Middle Archaic periods (10,500-5,200 BP). Samples were leached with 2N HCl and analyzed using ICP-AES for Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, Sr, S, and Zn. Preliminary results suggest that archaeological features chemically differ from natural sediments and that features such as hearths, burials, and middens can be readily distinguished from one another. Non-hierarchical, k-means cluster analyses indicate that activity features of known origin and suspected features of the same origin cluster together, thereby serving as a useful first step in feature identification. Phosphorus serves best as an indicator of human occupation intensity down core, while ratios of Sr/Ca and K/P help identify feature and activity function. Combined with micromorphological study of archaeological sediments, we conclude that geochemistry can be a powerful tool for interpretation of activities at stratigraphically complex archaeological sites. Using these techniques, archaeologists can reconstruct occupation intensity in areas not amenable to full-scale excavation, or can more rapidly select promising areas for detailed study. Moreover, they facilitate the identification of activities carried out at sites, such as food processing, refuse disposal, and burial. This information will allow archaeologists to reconstruct the changing use of archaeological sites through time.