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Big Eddy Site
The Big Eddy Site (23CE426) is an archaeological site located in Cedar County, Missouri, which was first excavated in 1997 and is now threatened due to erosion by the Sac River.
== Location and general description ==
The Sac River has created a cut bank, some 5.2 meters high, revealing a rare site similar to the Rodgers Formation of the neighboring Pomme de Terre valley (Lopinot et al. 1998:39-40). Haynes (1976:58-59) describes the deposits in the area of Rodgers Cave as flood plain deposits which have accumulated slowly through annual flooding. Periodically, the river would downcut deeply enough to prevent further flooding, only to change its course later and restart the process. This leaves a series of easily identified layers, separated by periods of no deposits. Big Eddy was formed in a similar way. For some 14,000 years, the Sac River has gently flooded, covering over this site with thick, well stratified, alluvial silt (Bush 2006).
This detailed stratigraphy has preserved a record of a nearly continuous human occupation from recent prehistory back to the earliest Clovis, and possibly pre-Clovis residents. Recovered artifacts show a continuum from Paleoindian through Archaic, Woodland, and Mississippian, including perhaps important evidence for the transition from the Clovis to Dalton cultures (Chandler 2001a; Joiner 2001).
Making the site even more valuable is the clear separation of deposits. The site was periodically sealed by gravel layers and paleosols, ancient soils preserved by burial under more recent sedimentation. These layers, often of very hard material, effectively seal the layers, preventing intrusion into the lower layers by later material. The paleosols are particularly valuable as they were formed by environmental changes that create a change in the soil forming a hard shell over the lower material.
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