1-Plan of Survey Area with Historic Sites

In conjunction with Panamerican Consultants, Inc. (PCI), GRA was subcontracted by the U.S. Army, Fort Benning, Georgia, to provide a non-invasive targeted survey of a Contact Period Native American site on an army airfield.

Remote sensing techniques were used to assess site boundaries, activity loci, and feature types across a tract of land separating active airstrips. GRA developed a flexible and cost-efficient testing strategy to map the undisturbed features of the site within constraints of time and limited access to airbase facilities. Using GRA’s baseline maps, field crews ground-truthed the archeological site and its features using traditional archeological testing methods. The correspondence between remote sensing anomalies and ground-truthed data proved to be accurate, and serves as a foundation for designing follow-up geophysical investigations.

The magnetometer survey began with Total Station mapping followed by magnetometer readings along 5 m transects across the project area. GIS maps highlighted modern utility lines and construction features and detailed images were used to interpolate archeological data for the northern portion of the project area, isolating probable activity areas for the historic Creek occupation.

A portion of the survey reflected an area of magnetic susceptibility isolated within the sensitive 10 nT (nanotesla) range. A compilation of three super-imposed maps was used to capture features of anthropogenic origin. The Surfer application was used to create a surface map that indicated the recorded nT range for the magnetic field. A contour map isolated the delimited 10 nT of enhanced susceptibility contrast, and a post map provided the location of the over 20,000 data points. An additional contour map provided a view of the total magnetic signature.