Geophysical Survey
Definition
Non-invasive subsurface imaging using physical contrasts such as radar reflection, magnetic variation, or electrical resistance.
- Common methods
- Ground-penetrating radar, magnetometry, resistivity
- Nature
- Non-invasive, subsurface imaging
- Field
- Forensic archaeology
- Basis
- Contrasts in physical properties
Common questions
How does ground-penetrating radar detect a buried grave or object?+
It sends radar pulses into the ground and measures reflections caused by contrasts in subsurface material, such as disturbed soil or a buried object, which appear as anomalies in the resulting radar profile.
Why use resistivity or magnetometry instead of radar?+
Different subsurface conditions favor different methods; resistivity often works better in wet or clay-rich soils where radar signal attenuates quickly, while magnetometry is effective at detecting buried metal or fire-affected soil.
Does a geophysical survey confirm what is buried without excavation?+
No, it only identifies anomalies consistent with a disturbance or buried object; excavation is still required to confirm and recover whatever caused the anomaly.
Related terms
- Remote Sensing
- Locating features from a distance using aerial imagery, satellite data, or airborne LiDAR, before anyone sets foot on the ground.
- Search Strategy
- A structured plan for covering ground systematically so that the probability of detection is known and the absence of a find means...
- Single-Context Recording
- Recording and removing each deposit as its own discrete unit, so the formation sequence of the scene can be reconstructed afterwards.
- Stratigraphy
- The layered record of deposits. In a grave, the cut, the fill, and the body each form contexts that must be read...
- Total Station
- An electronic instrument that simultaneously measures horizontal and vertical angles and distance to a reflective prism, computing three-dimensional coordinates directly. Typical angular...