The geoarchaeology of Dust Cave: a Late Paleoindian through Middle Archaic site in the western Middle Tennessee River Valley

This dissertation uses a geoarchaeological perspective in order to reconstruct the depositional history of Dust Cave. Dust Cave, located in the western Middle Tennessee River Valley, is a complex Late Paleoindian through Middle Archaic site. The cave contains uniquely well-preserved artifacts, and one of the earliest well-dated archaeological sequences in the southeastern US. The depositional history addresses the relationship of Dust Cave to the regional geomorphology and builds a contextual framework based on the cave's microenvironment. Microenvironmental conditions directly affected both the organization of human activity and its preservation.

The methodology employed consists of detailed macrostratigraphic field observations and micromorphological analyses of more than 130 sediment thin sections. Micromorphology is the most appropriate technique for the cave environment where fine-scale variation among the deposits is preserved and data from the anthropogenic sediments have the potential to inform about human activity. The zones are organized chronologically based on 46 radiocarbon ages and diagnostic artifacts.

When Late Paleoindian peoples began to occupy Dust Cave ca. 10,500 B.P. it had recently been flushed of sediment from a phreatic aquifer at the rear of the cave. The entrance chamber contained only a thin veneer of reworked alluvium overlying the bedrock floor in a ~10 m wide and nearly 8 m deep room with a 5 m high ceiling. Intermittent overbank deposition with limited reworked aeolian sediments and autochthonous sediments accumulated in the cave for the next ca. 2,000 years. During this time Late Paleoindian and Early Archaic peoples seasonally inhabited the cave. Microtopographic surface variation and the periodic resurgence of phreatic drainages controlled the organization and preservation of anthropogenic sediments. After ca. 8,500 B.P., when the floodplain began to stabilize, alluvial sediments were no longer actively contributing to the cave. Sedimentation over the next 3,000 years was primarily the result of human activity, which continues until ca. 5,200 B.P. when the cave is no longer habitable. Several interesting aspects of the depositional history are revealed including relic cold features deep in the sequence and the identification and distribution of prepared surfaces. These discrete anthropogenic structures have significant implications for technology and site formation.