The Geological Survey of Norway (NGU) has carried out airborne geophysical surveys since 1958. After covering mainland Norway and parts of the continental shelf with fixed-wing magnetic measurements, a program for high-resolution helicopter geophysics was started in the early 1970s.
The present instrument package includes magnetic, electromagnetic and radiometric measurements. Normally the radiometric sensor is mounted underneath the helicopter, while the magnetic sensor is placed inside the EM instrument suspended 30 metres beneath the helicopter. Nominal flying height is 60 metres above the ground and the speed is usually 100 km/h (approx. 30 m/sec.). Instrumentation and survey design are adjusted to suit client requirements. The equipment has changed several times since the first test measurements in 1972.
Method descriptons
- Magnetic methods
- Radiometric
- Electromagnetic methods - Slingram
Clients
During the last 25 years NGU has carried out high resolution surveys for mineral exploration, bedrock mapping and environmental studies both in Norway and in neighbouring countries.
Existing data
About 12 % of mainland Norway is covered with high resolution airborne geophysics. An overview of available data from NGU and a price list exist. For more details visit NGU's geophysical database (DRAGON)
Published: 29. January 2008