Ground Penetrating Radar
Ground penetrating radar records 3D images of sub-surface features. In archaeological investigations it can retrieve information otherwise only available through expensive, destructive and lengthy excavations.
Ground penetrating radar operates by transmitting pulses of ultra-high frequency radio waves (microwave electromagnetic energy) into the ground through an antenna. The transmitted energy is reflected from various buried objects or distinct contacts between different earth materials. The antenna then receives the reflected waves and stores information about them in the digital control unit.
Recent work by Durham University at a variety of sites has shown that it is most productive when used in combination with 2D and 3D modelling in Geographical Information Systems and alongside the traditional techniques of geo-prospection: gradiometry and resistivity.
This technique is now being tested at Yeavering over the main area of the palace site with some initial success. Although wet conditions make the ground unsusceptible, it works extremely well in cold conditions when the ground is frozen. It is being used by the Trust as an additional method of capturing below-ground data, offering a complementary resource to the information gathered from the LiDAR, gradiometry and resistivity surveys.