Ground-Penetrating Radar Techniques to Discover and Map Historic Graves

Ground-penetrating radar is a geophysical technique that can be used to identify and map features commonly associated with historic graves, including intact or partially collapsed coffins and vertical shafts. Data are collected by moving radar antennas that transmit pulses of energy into the ground along parallel transects within grids, recording reflections of those pulses from significant discontinuities within the ground. Visual analysis of radar reflection profiles can be used to identify both coffins and the vertical shaft features commonly associated with human burials. Spatial analysis of the reflection amplitudes within a grid consisting of many profiles (when converted to depth using site-specific velocities) produces three-dimensional maps of these burial features. The identification and mapping of graves can identify remains for possible excavation and study, and the results can also be used for statistical and spatial analysis when integrated with historical records. If identified by these methods, previously unidentified graves can be preserved in areas threatened by construction or erosion.