Geophysical prospecting

The geophysical prospecting is a branch of applied geophysics and deals with the exploration of the upper portions of the earth's crust and sometimes ground-level underground. Gravimetric, seismic, magnetic and electrical methods are used:

• With gravimetry (high-precision gravity measurement), differences in rock density in the subsurface can be determined and the coarse structure of the earth's crust can be recorded. At close range it is also suitable for creating a rock appearance
• Using seismics , the upper crust of the earth (up to a depth of around 10 km) is explored by artificially excited seismic waves and displayed graphically or digitally. As a land seismic it is an important method for the first exploration of possible oil and gas deposits , as a sea ​​seismic also for pure research purposes
• Using geomagnetics , anomalies in the earth's natural magnetic field are investigated, which suggest the existence of magnetic rocks or clay minerals . It is used in geology , for prospecting deposits , in environmental protection (contaminated sites in the soil) and in archeology .
  Especially economical is the aeromagnetics , but the interpretation is ambiguous to be
• with ground penetrating radar ( radio echo sounding ) the nearby subsurface is scanned using high-frequency electromagnetic waves . Important applications are in archeology, environmental protection and landmine detection
• With geoelectrics , ground layers in particular are explored by measuring electrical voltage and current . Ore deposits reveal themselves through their own potential, with direct current and alternating current processes electrodes feed artificial currents into the soil.

In some cases, geological and related methods can also be used for prospecting, for example

• the analysis of subsidence , subsidence and landslides ,
• the investigation of fissures in rock formations
• the airborne laser scanning and other methods of remote sensing .

literature

• Friedrich Bender (Ed.): Applied Geosciences. Volume 2: Methods of applied geophysics and mathematical processes in the geosciences. Enke, Stuttgart 1985, ISBN 3-432-91021-5 .
• Norbert Buthmann: Geophysical prospection and garden archeology - one concept . In: Die Gartenkunst  27 (2/2015), pp. 231–244.
• László Egyed : Solid Earth Physics. Akadémiai Kiadó, Budapest 1969.