USING GROUND PENETRATING RADAR TO ANALYZE BURIED HISTORY AT OLD FORT NIAGARA

Ground Penetrating Radar (GPR) is a non-invasive geophysical tool that uses electromagnetic waves to analyze the subsurface. Radar waves sent into the ground from an antenna interact with differences in electrical properties to create a 2D view of the subsurface. Resulting radargrams reveal objects including pipelines, building foundations, stratigraphic layers, and burials. This is useful in scientific applications including archaeology, near surface geology, engineering, and environmental studies. Additionally, collecting data in a precise grid pattern allows for a 3D block of data to be obtained by combining parallel 2D views and using processing software for interpolation. The resultant 3D visualization allows for more complete interpretations of data compared to individual 2D profiles.

In this study, a GSSI SIR-3000 system was used at Old Fort Niagara in Youngstown, NY, to better understand the buried history of the fort. Eight parallel grids of data were collected over a 3,000 square meter area of the fort and were combined into one 3D block of data. Due to varying accuracies of the fort's historical maps, a previous study used computer assisted cartography to reorient the maps and aid future archaeological studies. These maps were compared to GPR data using ArcGIS to aid interpretation, as well as to better understand remaining archaeological features at the fort. Interpretations were then used to create an accurate map of existing archaeological features for the Buffalo State Archaeological Field School's ongoing excavations.

The resultant map shows the remaining building foundations with corresponding depths, as well as accurate locations of utility lines, trash pits, hearths, and a past seawall. Some of the historical maps were also accurately georeferenced in order to compare locations of foundations revealed in GPR data to what was recorded historically.