What is ground-penetrating radar primarily useful for determining?

Ground-penetrating radar (GPR) is a geophysical method that uses radar pulses to image the subsurface. It is particularly effective for determining the locations of buried objects, as it can identify changes in material properties at varying depths. GPR sends electromagnetic waves into the ground, and when these waves encounter an object or a boundary with different physical properties (such as a buried pipe, cable, or even archaeological artifacts), they are reflected back to the surface. The data collected can create detailed images of what lies below the surface.

This capability makes GPR an invaluable tool in various applications, including archaeology, utility mapping, and environmental investigations. While GPR can indeed help determine the depth to shallow groundwater in certain conditions, it is not primarily designed for that purpose and is less effective in fine-grained sediments that may attenuate the radar signals. Additionally, it is not used to measure the earth's magnetic field or to determine the depth to bedrock beyond a certain range due to diminishing returns in data quality with increased depth. Its primary strength lies in detecting and mapping out visible objects and structures buried in the subsurface.