Geoarchaeology and Bayesian Statistical Modeling of Radiocarbon Dates from 40CH171, a Multicomponent Shell-Bearing Site in Cheatham County, Tennessee

Using multiple lines of evidence from 40CH171, including opportunistic sampling, geoarchaeology analysis, and Bayesian radiocarbon modeling, this chapter constructs a site formation process narrative based on fieldwork conducted from 2009 to 2010 by the University of Tennessee, Middle Tennessee State University, and the Tennessee Division of Archaeology. This chapter argues that the shell-bearing strata were deposited relatively close to an active channel of the Cumberland River and/or Blue Creek during the Middle Holocene (ca. 7170–6500 cal BP). This was followed by an abrupt shift to sandier sediments, indicating that deposition after the termination of the shell-bearing deposits at the Middle Archaic/Late Archaic boundary took place in the context of decreasing distance from the site to the Cumberland River and Blue Creek.

Archaeological Investigations at 40DV7

The Middle Cumberland Archaeological Project is a multi-institution research effort launched in 2010 that includes archaeologists with Florida State University, the Tennessee Division of Archaeology, and Middle Tennessee State University, working together to identify and assess Archaic shell-bearing sites in the western Middle Cumberland River Valley of Tennessee. In 2012, the project investigated the substantial Archaic shell-bearing deposits at archaeological site 40DV7, located on the Cumberland River in Davidson County, Tennessee. This interdisciplinary project gathered basic site-level data regarding the horizontal and vertical extent of cultural deposits, radiocarbon assays to determine site chronology, bulk and column samples for flotation and water-screening to aid in zooarchaeological analysis and paleoethnobotanical analysis, and geomorphological samples of the immediate environment. The results of the 2012 excavations, combined with earlier data collected by the senior authors, provide significant new data about the occupation history and freshwater shellfish composition of this site. In addition, radiocarbon data presented in this chapter reveal that 40DV7 manifests the longest continuous Archaic shell-bearing occupation yet identified in the region, spanning the period ca. 6500–4500 cal BP.

Introduction

This introduction presents a brief geologic overview of the Middle Cumberland River Valley of Tennessee. It describes the research interests that culminated in the creation of this volume and positions the volume within the overall context of Archaic shell-bearing site excavations in the Southeastern United States and the Shell Mound Archaic culture phase. The introduction further summarizes the prevailing theories as to the creation and function of Archaic shell-bearing sites which have been generated by research in other regions of the coastal and interior Southeast. Finally, it presents a short overview of the contributed chapters.

Modeling Archaic Settlement Patterns and Ecology in the Middle Cumberland River Valley of Tennessee

Spatial analysis provides a greater understanding of relationships between people and environment. This chapter discusses settlement patterns and settlement ecology of the Middle Cumberland River Valley of Tennessee through spatial analysis and a settlement ecological approach. Multiple lines of evidence are necessary to distinguish between survey bias and archaeological patterns. This chapter examines Archaic settlements at local and regional scales using GIS-based analyses, exploring the environments that people chose to settle and the possible relationship of these choices to horticulture and gathering, and highlighting Archaic patterns with consideration of data limitations. The lower number of sites in the region during the Middle Archaic could suggest a return to a residential mobility strategy, while the Late Archaic yielded more logistical mobility. Decrease in site numbers and elevation from the Early to Middle Archaic could be tied to temperature fluctuations during the Altithermal. Some Late Archaic sites occur at slightly higher elevations, indicating perhaps more varied resources.

Investigations at the Robinson Site (40SM4)

Excavations at the Robinson Shell Mound site took place during the summer of 1963 and recovered more than 22,000 artifacts during what would be the first modern archaeological investigation of a shell-bearing site within the Middle Cumberland River Valley. The results of the excavations were synthesized by Morse for his 1967 PhD dissertation from the University of Michigan. In that work, Morse was one of the first to propose that the inhabitants of Robinson and similar shell-bearing sites were part of a larger regional economy based on white-tailed deer hunting, especially during winter congregations, and used shellfish as secondary resources. This discussion presents the first widelyaccessible summary of findings at the Robinson site and also presents previously unpublished data on zooarchaeology materials.

Investigations at the Barnes Site (40DV307)

At the Barnes Site (40DV307) along the Cumberland River, two discrete shell-bearing deposits dating to the Late Archaic and Middle Woodland periods (approximately 3500 and 1800 cal BP respectively) are separated by a thick Early Woodland–period shell-free stratum dated between 2900 and 2000 cal BP. Alternating shell-bearing and shell-free deposits at sites elsewhere in the southern Ohio Valley have often been viewed as indicative of long-term changes in subsistence practices and traditions or large-scale environmental fluctuations affecting resource abundance. At Barnes, however, chronological, geoarchaeology, and paleoethnobotany data from shell-bearing strata recovered in 2010 and 2012 suggest that the two shell-bearing deposits mark the locations of shellfish processing at or near the river’s edge when the river channel was physically closer to the current site location. Particle-size data indicate that when the shell-free deposit accumulated, the site was situated in a low-energy depositional zone, suggesting that the river channel had shifted further to the west during that period of time.

The 2010 Cumberland River Survey Emergency Survey and Archaic Shell Site Composition in the Western Middle Cumberland River Valley

Over three days beginning in the early morning of May 1, 2010, heavy storms caused severe flooding and riverbank erosion along portions of the Cumberland River throughout Middle Tennessee. That event caused significant damage to numerous prehistoric archaeological sites, and resulted in substantial looting of newlyuncovered site deposits and subsequent shoreline assessments of 128 previously recorded prehistoric sites along 67.5 river miles of the Cumberland River between Cheatham and Old Hickory Dams, as well as sampling of selected, highly endangered deposits. As a result of the emergency river survey, investigators were able to collect significant new data regarding the composition of nine shell-bearing Archaic sites along the Cumberland River in the western Middle Cumberland River Valley of Tennessee. Those include new information regarding site composition and the collection of radiocarbon samples. This chapter describes the history of archaeological site disturbance in the region and summarizes the findings of the post-flood survey as they relate to molluscan species composition of Archaic shell-bearing sites in the region.

A New View of the Shell-Bearing Archaic in the Middle Cumberland River Valley

While Archaic shell-bearing sites along the coastal margins of the southeastern United States have been the subject of multi-year investigations, interior riverine shell-bearing sites have, with the exception ofCarlstonAnnis on the Green River in Kentucky, garnered only limited study. Nevertheless, the combined data from coastal and interior shell-bearing sites have led to broad regional interpretations of the Shell Mound Archaic and debate between archaeologists about site construction and function. Archaic shell-bearing sites in the southeastern United States vary widely in terms of chronologies, horizontal and vertical structure, the types of cultural features they contain, and molluscan species composition. This has led to a growing realization that Archaic shell-bearing sites cannot—or should not—be lumped into a single pan-regional culture and that the “mound vs. midden” debate presents an interpretive logjam that does not satisfactorily address local and regional variations. The specific chronologies and composition of Archaic shell-bearing sites in the Middle Cumberland River Valley of Middle Tennessee constitute a unique regional phenomenon distinct from other interior riverine sites lumped within the Shell Mound Archaic paradigm.

Reassessing Middle Archaic Stratigraphy and Chronology of the Anderson Site

The Anderson site (40WM9) is located on the Harpeth River in Williamson County, Tennessee, and is the only shell-bearing Archaic site off the main channel of the Cumberland River in the Middle Cumberland River Valley to have undergone controlled archaeological testing. The site is further significant in that it is the oldest known shell-bearing Archaic site in the region and despite its size and depth presents a mid- to lateMiddle Archaic component with no direct evidence of occupation before or after that time. In addition, the Anderson sitehas produced some of the earliest evidence from the interior Southeastern United States for long-distance trade of marine shell. However, while the Anderson site has been widely cited in the literature on Archaic adaptations in the interior Southeastern United States, much of the data from the site have never been synthesized in a modern professional setting. This chapter presents a modern reexamination of the data from Anderson, for the first time fully correlating the site stratigraphy and associated cultural phases. When combined with Bayesian analysis of radiocarbon data, this effort clarifies the duration and sequence of site occupation and places it within the framework of more recent data from the region.

Archaic Shell-Bearing Site Investigations in the Middle Cumberland River Valley

Our understanding of the archaeological sequence in the Middle Cumberland River Valley is the result of thousands of archaeological projects conducted over the past century by antiquarian scholars, archaeological consultants, state and federal agency archaeologists, colleges and universities, and through the efforts of Tennessee’s avocational archaeological community. However, most of the data on Archaic shell-bearing sites generated by these investigations consists of archival sources or gray literature reports and have not been widely reported or previously summarized. This chapter presents a history and descriptive data on archaeological investigations at Archaic shell-bearing sites in the Middle Cumberland River Valley to date. This information is drawn from a variety of sources including technical reports, unpublished archival materials housed at the Tennessee Division of Archaeology in Nashville, interviews with artifact collectors and members of the avocational community, and field inspections.