Tristram R. Kidder (Ph.D., Harvard University, 1988)

Professor

I am currently working on four interrelated research projects all having the common focus of understanding human social, political, and economic evolution in Eastern North America from ca. 4000 BC to European contact. Much of my work uses geological and geoarchaeological data to examine questions of concern to the human occupation of the very dynamic landscape of the Mississippi Valley. The first three projects I am working on are located in northeast Louisiana. The last one has its origins in that area but has extended to encompass the entire Mississippi River Basin.

The first project is an ongoing excavation at the Raffman site in Madison Parish Louisiana. Raffman, a large multi-mound site, was occupied sporadically from ca. 500 BC to 1200 AD. The mounds were constructed ca. 800-1200 AD during the Coles Creek period. Our work at Raffman is dedicated to understanding the site, its history, and its significance in Coles Creek social and political history in the Mississippi Valley. We have conducted work in 1998, 2000, 2001, 2002 and 2003 and plan to do a limited amount of work in the summer of 2004. Our excavations and mapping have extended to several other sites in the region, notably the Early Woodland Borrow Pit and St. Mary sites.

Our research has revealed that the site was located on the surface of a large crevasse that formed during major flooding off of Joes Bayou (5 km to the west) ca. 900-600 BC. Although the site area was intensively occupied in Early Woodland times, it was not until the beginning of the Coles Creek period (ca. 700 AD) that the site achieved a significant role in the local social and political realm. By ca. 1000 AD Raffman was the largest or one of the largest Coles Creek centers in the Lower Mississippi Valley. In addition to building nine mounds, the inhabitants of Raffman constructed the plaza by creating an artificial terrace over 100 m wide, 50 m deep, and 5 m tall. By 1200 AD Raffman appears to have been an active center in the region political network, but it was suddenly abandoned due to the deposition of thick clay sediments probably caused by flooding consequent to a shift in the course of the Mississippi River to the east.

At present our work at the site is concentrated on Mound B, where Lori Roe, a graduate student at Tulane University is working under my direction. Her research is examining the function and use of Mound B, especially examining evidence for how (and/or if) he mound was used by elite inhabitants during the Coles Creek and earliest Mississippi periods. Lori is also doing work on Mound G to see how its use and function relate to the emergence of Raffman as a major political center. Our work suggests that in contrast to contemporary sites to the east (Lake Providence or Routh sites) Raffman's populations were not participating in extensive trade with groups farther north and they may represent a marginal polity due to geographic isolation along the western edge of the alluvial valley.

A second project is mapping, coring, and testing at Poverty Point. This work, which is largely being done by Anthony Ortmann at Tulane University, is aimed at understanding the chronology and use of the mounds at this remarkable site. Excavations in 2001 in mounds C, D, and E, as well as coring in mounds A and B have provided new evidence on these features. Mounds B and E show that they have a similar architectural history and that both were built with an initial stage composed of fine gray silt. This material in Mound B was thought by Ford and Webb (1956) to be ash from a large cremation fire, but we have demonstrated that it is simply material derived from an E horizon sediment. We also derived a date of ca. 1500 BC for the initial stage of Mound B.

Work on the materials from Mounds C and D is ongoing but it is likely that Mound D is actually a remnant of Ridge 2, while Mound C is certainly a stratified mound. Coring at Poverty Point has expanded our appreciation of the earthmoving at the site and shows that large areas of the site were either leveled or filled by the initial inhabitants in the Late Archaic.

A third excavation project is just being designed and is aimed at exploring the Nolan site. Nolan has four mounds, the largest being ca. 3.5 m tall. However, the site is over 2 km from the nearest source of water and it appears to be deeply buried by later alluvium. The base of the large mound appears to be at least 3 meters below the modern surface. Coring in 2002 revealed mound strata in mounds B and C that have been radiocarbon dated to more than 5400 BP. Nolan appears to be the first late Middle to early Late Archaic mound located in the alluvial valley of the Mississippi River as well as one of the oldest mound sites in North America. Work at Nolan will concentrate on understanding the site's geology and environment as well as its basic culture history and function. We anticipate working at Nolan in 2004 and also 2005.

My final research project is a detailed study of flooding in the Mississippi River Valley and its effects on human occupation. This work grows out of the research at Raffman and Nolan (and to some extent the research at Poverty Point). In northeast Louisiana there is considerable evidence that flooding had a major effect on human groups and I am pursuing evidence that it may have led to significant gaps in the archaeological record. Initially this work is being done in northeast Louisiana with an extensive coring project in the alluvial floodplain. I intend to continue this project upriver to work in west-central Mississippi, and eventually southeast Missouri.

The working hypothesis is that flooding caused by large-scale climate changes led to a near abandonment of the alluvial valley ca. 1000-500 BC. It is possible that other flood events, some possibly linked to climate change and some of local magnitude, played a role in the evolution of groups living in the Mississippi Valley and its watershed.                                                        

In addition to work in the Lower Mississippi Valley my students have been or are working in the Moundville area of Alabama, the Mobile Delta of Alabama, and south-central Arkansas.

Contact: Dr. Tristram R. Kidder, Department of Anthropology, Campus Box 1114, Washington University, One Brookings Drive, St. Louis, MO 63130 (314-935-5242)