Multi-method geophysical investigation at Snow's Bend, a Mississippian platform mound

Abstract

Archaeological investigations of Mississippian platform mounds have traditionally required invasive excavation or coring. Excavations are damaging to sites, and in many cases, invasive or destructive research methods on Native American mounds are forbidden or inappropriate. Non-invasive geophysical investigations avoid these issues but have their own challenges in terms of resolving the interior of the mound, particularly if electrically conductive materials, such as clay, are present. Here, we present a multi-method non-invasive geophysical approach using ground penetrating radar, electrical resistivity tomography, time-domain induced polarization, and electrical resistance mapping to study the Mississippian platform mound at Snow's Bend (1TU2/3), a late Moundville II/III (ca. AD 1300 to 1520) site located near Moundville, Alabama. From our data, we interpreted at least two construction stages and found indications of remnants of summit architecture on each. The final, as well as earlier, construction stage of the mound had a two-tier summit with a lower platform in the northern half of the mound. Summit buildings were identified on the lower platforms of each mound stage. We acknowledge that there is inherent uncertainty with any non-invasive approach, but demonstrate the capabilities of geophysics for new understandings of the life-histories of Mississippian platform mounds.