Ireland has become one of the few countries in the world to complete a detailed airborne geophysical survey. After 16 years and over 440,000 km of flying the Tellus Programme has undertaken its final flight.
The airborne survey took off in 2011 in the border region, with European Interreg cross border funding. The Tellus Programme, managed by Geological Survey Ireland a part of the Department of Climate, Energy and the Environment then became a national survey funded by the National Development Plan. This final flight will mark national coverage ensuring data has been collected from all corners of the country. This makes Ireland one of the best geologically mapped countries in the world and a leader in geophysical survey data in Europe.
The airborne survey operated by specialist Canadian company Sander Geophysics Ltd collects magnetic, electromagnetic and natural radioactivity data from the rocks and soils below our feet. The data is turned into maps and is used to help support the management of our natural resources, assist environmental monitoring, help identify radon risk areas as well as improving geological mapping.

Geological Survey Ireland Director Koen Verbruggen said:
"After 16 years, I am delighted to see the final survey flight and completion of the Tellus airborne geophysics survey. More hard work follows in investigating, modelling and mapping the data. However, this is a hugely significant moment for Ireland as we will have better scientific data to help make decisions on how we best manage our natural resources. We will be making this data freely available, and I look forward to seeing it support policy, industry and research in a variety of areas. Finally, I would like to thank all who have been involved in this fantastic project.”
Data have been processed and is currently available to download from the GSI.ie website for about 80% of the county. The final data will be merged with all the other survey data and be available in 2027. All data and maps are free to download.
Due to the low flying nature of the aircraft, flying at an altitude of 60m, an extensive operational communications programme was undertaken. We would like to thank all the team along with all landowners and stakeholders for their assistance and co-operation over the last 16 years. Equally we appreciate the skill and dedication of the pilots who have probably seen more of Ireland than anyone else. Due to the delicate nature of the instruments on-board and the technical requirement not to fly in rain, wind or cloud, considerable patience was required by all stakeholders involved. However, that patience has been rewarded and the national datasets produced will be of great benefit to the state in the future.