Geologic research to study the timing and pacing of mound construction at the Coles Creek period (ca. A.D. 700–1200) Raffman Mound Center as well as investigating possible environmental factors contributing to the site’s abandonment.
This project, funded by Murray State University’s Committee for Institutional Studies and Research (CISR), uses geoarchaeological analyses of sediments to explore the timing and pacing of mound construction and midden deposition at the Coles Creek period (ca. A.D. 700–1200) multiple-mound center of Raffman, located in Madison Parish, northeastern Louisiana. The on-going work is being carried out by Lori Roe, Department of Geosciences at Murray State University (MSU) in Kentucky and Lara Homsey-Messer, Department of Anthropology at Indiana University of Pennsylvania (formerly of MSU). Homsey-Messer and Roe spend part of the summer of 2012 sampling mound and plaza sediments to investigate mound construction and possible flood deposits that may have prompted residents to abandon the site.
Competing hypotheses about Coles Creek mound centers state that 1) mound centers were chiefly compounds where groups of elites lived, and/or 2) mound centers were vacant ceremonial centers where people periodically gathered for social and ritual events.
Previous archaeological research at the Raffman mound site supports the second hypothesis: excavation of the mound summits failed to reveal evidence of permanent residential locations, and stratigraphic observations suggests that mounds were constructed rapidly and some middens resulted from short-term events.
Geoarchaeological research supports the interpretation that the mounds were built rapidly during periodic gatherings at the site. Preliminary interpretations of geological samples from Mound B suggest that the mound was constructed rapidly and continuously using a combination of locally available silty river sediments and clayey wetland sediments, a mix that may have been intentionally designed to maximize stability and drainage. Thick midden on the slope of the mound also appears to have been deposited rapidly in a single event. Finally, sediments from the plaza suggests that repeated low-energy flooding may have affected low-lying areas, possibly a factor contributing to the site’s abandonment. Future analysis will examine comparative samples from additional mounds as well as the artificially constructed terrace northeast of Mound B.