Integrating geochemistry and micromorphology to interpret feature use at Dust Cave, a Paleo-Indian through Middle-Archaic site in northwest Alabama

The authors develop an integrated method using geochemistry and micromorphology to examine the use of archaeological features at Dust Cave, a Paleo-Indian through Middle Archaic (10,650-3600 cal. B.C.) site in northwest Alabama- Samples analyzed using ICP-AES for aluminum (Al), barium (Ba), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), phosphorous (P), strontium (Sr), sulfur (S), and zinc (Zn) and suggest that cultural features differ chemically from geogenic sediments in several ways: (a) K-means cluster analyses indicate that features of known origin and suspected features of the same origin cluster together, thereby allowing for a preliminary separation into discrete functionalities; (b) phosphorus serves as an indicator of human occupation intensity; and (c) Sr/Ca and K/P ratios help identify anthropogenic materials. Micromorphological observations allow for a finer subdivision of feature types and help highlight postdepositional processes affecting cave sediments, and interpretation of activity at the site. These findings show that feature diversity and occupation intensity increased through time, peaking during the Middle Archaic. (c) 2006 Wiley Periodicals, Inc.