BGS has carried out geophysical surveys in many countries for different agencies. The surveys range from regional gravity and airborne magnetic mapping to targetted surveys for mineral and water. Individual surveys do not yet have metadata entries: this entry describes a notional database that represents all overseas geophysical surveys.

Airborne geophysical data acquired as part of the BGS-NERC TellusSW project (http://www.tellusgb.ac.uk/) during the second half of 2013. The survey comprised a high resolution magnetic/magnetic gradient survey combined with a multichannel (256 channel) radiometric survey. The survey was carried out using 200m (N-S) line separations at a mean elevation of 91m. Encompassing the counties of Cornwall and parts of Devon and Somerset, the survey provided 60,323 line-km of data. Digital data and derived (e.g. spatial derivatives) maps of the geophysical information are provided to facilitate spatial modelling of the soil, geological and environmental aspects of the data.

The high-resolution airborne surveys shown on the map based index (GeoIndex) are classed as those flown with low terrain clearance (typically below 200m) and flight line spacing of less than 300m. The surveys were flown with various combinations of magnetic, radiometric and EM techniques, and include; Surveys flown for the DTI mineral reconnaissance programme, Commercial surveys flown for mineral exploration and subsequently donated to the BGS and Surveys flown for the BGS for research and other purposes.