AEM / AEROMAG Surveys

 Airborne geophysical surveys in Greenland conducted by GEUA/GGU from 1992 to 2013

The regional AEROMAG 1992-2013 surveys

The AEROMAG projects encompass high-resolution and good quality magnetic surveys conducted in 1992 and each of the years from 1995 to 1999, in 2001, 2012 and 2013, producing a total of nearly 570 000 line kilometers at a regional scale. The overlapping surveys (size: ~300 000 km²) cover the total ice-free and near-coastal offshore area from West, South and southern East Greenland ranging from Svartenhuk Peninsula in the central west to the Kronprins Frederik Bjerge in the southeast. All surveys are gathered by airplanes with similar flight line distances of 500 – 1000 m and 5000 m in inline and cross-line direction, and similar flight altitudes along gently draped surfaces 300 m above the ground level or seafloor such that they could be integrated to one consistent high-quality magnetic dataset.

Total magnetic field data are recorded with a sampling rate of 0.1 sec which corresponds to a sampling distance of 7 m. Aircraft positional data from simultaneous GPS measurements, as well as aircraft altitude measurements obtained from barometric altimeter and radar are recorded.

The magnetic data from the AEROMAG project have been frequently used for a wide range of purposes including regional geological mapping and determination or refinement of structural settings relevant for both mineral and hydrocarbon exploration. They have also been very useful for strategic planning of geological mapping campaigns and more detailed geophysical studies.

List of Aeromag Surveys

The AEM Greenland 1994-1998 surveys

The AEM Greenland 1994–1998 detailed surveys with combined electromagnetic and magnetic measurements were carried out in six selected areas of expected high mineral potential in North, North-West, South-West and Central East Greenland. In total, 75 000 line km covering an area of 23 000 km² were measured in the project. Line spacing is denser (inline: 200 – 400 m) and flight altitudes of ~120 m lower than in the AEROMAG surveys resulting in higher resolutions.

With exception of one survey the collected electromagnetic data were time-domain data (GEOTEM system). For the AEM 1996 survey in South-West Greenland, frequency-domain EM data and VLF data are gathered instead and, in addition, gamma-ray spectrometry data were collected. 

The project was initiated and designed to encourage mineral exploration at that time. The selection of areas was primarily guided by the knowledge of mineral occurrences but also to some extent by a wish to cover different types of geological settings.

Bjørn Henning Heincke
Senior Researcher
Geophysics and Sedimentary Basins

Areas of Aeromag and AEM geophysical surveys from GEUS and GGU in Greenland collected between 1992 and 2013

 

 

 

Magnetic grids from AEM1994-1998 surveys