Unterwasser-Prospektion
This part of the field research deals with the discovery of settlement remains and objects embedded in the bethic zone. Here surface photographs can be distinguished from methods that penetrate the soil layers.
Surface
- Sonar
This method (echo-location of sound signals) measures the water depth and generates a surface relief while precise measuring points are positioned. Some frequency ranges can also detect the density of the surface layer and thus distinguish, e.g. between mud areas and bare gravel. - Side Scan Sonar
Obliquely emitted sound waves create a silhouette of the ground relief visualising objects close to the bethic zone. - ROV (Remote Operated Vehicle)
Controlled diving device with camera and headlight (live image at the upper water control unit)
Ground-penetrating
- Sonar
Some frequency ranges can penetrate the uppermost soil layers and represent their layer structure - Sub-Bottom Profiler
The echo of high-energy high-frequency impulses provides information about soil layers or buried objects. - Metal detectors
generate with pulsed magnetic fields eddy currents in metallic objects that cause signal changes in the receiving coil.