High-resolution soil characterization of Topper Site soil shows evidence of paleoenvironment and overprinting

Topper (38AL23) is a stratified archaeological site with Archaic and Paleoindian components, adjacent to the Savannah River in South Carolina, United States. Much is being done to investigate the Clovis culture evident here, as well as the suggested presence of a people in the New World before Clovis. Topper is unique due to its artifacts found intact within the stratigraphy, while in many Southeastern sites, artifacts are found only at the surface. The chemical, physical and mineralogical characterization of soils at Topper are studied at high resolution (~5 cm interval) here to understand past and present soil-forming processes and their relation to Archaic and Paleoindian artifact layers. Preliminary results show that replicate soil bulk density of artifact layers is lower (1.2 g cm-3) than overlying and underlying soil (1.3 g cm-3). This decrease in bulk density coincides with an increase in organic matter (OM) content in both artifact layers. The mean soil pH for the profile is strongly acidic (5.3±0.3). The soil pH for the Archaic layer is moderately acidic (5.9); whereas, the pH for the Paleoindian layer is very strongly acidic (4.6). Although the bulk density and OM content are similar the soil pH differs for the two artifact layers. These differences in soil pH are discussed in terms of paleoenvironment and soil overprinting, the latter of which is reflected by higher clay content accumulated at artifact layers. Particle size, micromorphology and mineralogy are forthcoming. Despite a lack of pronounced soil profile differentiation in the field, high-resolution characterization of Topper soil show evidence of the paleoenvironment of human habitation areas and overprinting from modern soil formation