Ground Penetrating Radar (GPR) can “uncover” buried features without ever disturbing the ground. Learn more about GPR, how it works, and how it can be applied to projects in this Q&A with ERO GPR Specialist and Archaeologist Shayleen Ottman.
Sometimes called Ground-Penetrating Radar, ground penetrating radar, or GPR….What is it?
Ground-penetrating radar (GPR) is a non-invasive geophysical survey method that can be used to “see” objects buried underground. Using electromagnetic energy, an antenna is passed along the ground surface and registers signals as they bounce off buried objects or cavities. With an idea of what’s being looked for, careful analysis and experienced interpretation are used to determine the nature of the object that creates the signal.
Because GPR is non-destructive and non-invasive, GPR is ideal for locating buried features in sensitive areas, such as cultural sites, historic places, and monuments. For cemeteries with uncertainties surrounding the location of burials or those with gaps in their burial records, a GPR survey can be used to help cemeteries identify which plots are empty, and which are occupied. GPR can also be used to locate features such as roads, walls, foundations, ditches, and hearths that may have been buried over time, or disturbances such as past excavations.
Who uses GPR?
A GPR survey can assist archaeologists, historical societies, and other cultural stewards who may be planning projects that require underground investigations but wish to limit ground-disturbing activities. Beyond it’s cultural and historical applications, GPR is often used to identify underground utilities before construction!
What makes it so useful?
GPR can identify buried features over a relatively large area without the destructive nature or significant cost of systematic shovel testing, auger probing, or trenching. GPR surveys are ideally suited for projects with an aim to locate features in areas that are considered culturally or environmentally sensitive.
GPR sounds especially useful for historical societies – how can they get funding for GPR projects?
Grants through entities like the Colorado State Historical Fund, the National Trust for Historic Preservation, and other preservation organizations can often help clients meet their preservation and management goals. ERO can assist with the grant application process and help develop a project that meets the needs of both the client and the agency through which funds are provided. Often, elements of community involvement are stipulated as a part of a grant award. ERO provides public demonstrations of how GPR is being used for the benefit of the project and the community.