Hyperbolic anomaly
Definition
The characteristic arch shape that point-like or cylindrical subsurface targets produce on a radargram. As the antenna passes over a discrete reflector (pipe, bone cluster, grave edge), it picks up the target from a range of angles, creating the curved form. The apex marks the target's position.
Related terms
- Antenna frequency
- The centre frequency of the radar pulse, typically expressed in megahertz. Higher frequencies give finer resolution but penetrate less deeply. Lower frequencies...
- Dielectric permittivity
- A soil's capacity to store and transmit electric field energy. Higher water content raises permittivity and slows the radar wave. The contrast...
- Radargram
- The cross-sectional image produced by a GPR survey. The horizontal axis represents distance along the survey line; the vertical axis represents two-way...
- Two-way travel time (TWT)
- The time from transmission of a pulse to receipt of its reflection. Depth is calculated as: depth = (velocity × TWT) /...
- Velocity calibration
- The process of estimating the true electromagnetic wave velocity in the survey soil, usually by fitting a hyperbola to a known reflector...
Explained in
- Ground-Penetrating Radar (GPR)The characteristic arch shape that point-like or cylindrical subsurface targets produce on a radargram. As the antenna passes over a discrete reflector (pipe,...