The Bigger Picture: Using Landscape Archaeology to Better Understand Two Late Archaic Shell Rings on St. Catherines Island

Submitted by Ginessa Mahar (gmahar@amnh.org)

Archaeological crews from the American Museum of Natural History have been excavating on St. Catherines Island for over 30 years. This fall we returned to the island with a very specific, yet far reaching research plan.

Over the past four years, much of our research has focused on two Late Archaic shell rings (2400–1800 B.C.); the St. Catherines Shell Ring and the McQueen Shell Ring. These sites are roughly 70 m in diameter and are represented by a ring of deposited marine shell that measures about 10 m wide and 2 m deep and an interior “plaza” that measures between 30–40 m in diameter (see The Profile, Winter 2008 for a brief synopsis). Our research at these sites thus far has been comprised of geophysical prospection (soil resistivity, ground penetrating radar, gradiometry, topography, and shell density) and both minor and major archaeological testing (shovel test pits, vibra-cores, test units, trenches, and block excavations). Despite all of this work, we have been ignoring one of the most intriguing aspects of these sites; the surrounding landscape.

To better understand the archaeological landscape around the rings, we conducted a shovel test pit survey (at 20-m intervals) around the St. Catherines shell ring in the fall of 2008. Out of 458 shovel test pits, only 7 produced ceramics that are contemporaneous with the shell ring. The data suggests that the ring was the only substantial Late Archaic presence in this section of St. Catherines Island. This interesting revelation sparked a series of questions concerning the landscape the shell rings occupy. For instance; do contemporaneous sites exist outside the shell ring? During what other time periods did people utilized this space? What are the stratigraphic differences/similarities between the rings?

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Marc Lorenc and Leigh Davidson excavating a shovel test pit at McQueen Shell Ring.

With these questions in mind we devised a survey that would incorporate our previous shovel testing while at the same time improving on the quantity and quality of information previously gained. A 20-m shovel testing interval was conducted within 250 m of the shell ring while an additional finer 10-m interval was used within 150 m of the ring.

Fieldwork for this project has just wrapped up and therefore, specific results of the survey are pending. However, preliminary distribution maps generated in the field have provided some interesting insights. The area immediately surrounding the shell rings seems to lack any Late Archaic material, suggesting a lack of significant contemporaneous activity around the rings that would lead to deposition events. The only contemporaneous Late Archaic material comes from 3–4 isolated test pits 100–150 m away from the ring.

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GIS map of the McQueen Shell Ring (shell density in blue at center) surrounded by proposed 10- and 20-m interval shovel test pits. The green circle marks the 150-m radius; the blue circle marks the 250-m radius.

This survey has given us a fantastic opportunity to juxtapose two intriguing archaeological sites and their archaeological surroundings. Currently we have plans to complete the artifact analysis and integrate those data with our current GIS platform in the effort to better understand the distribution of material culture and the landscape setting upon which these shell rings exist.

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