Geological Survey Ireland Programme Updates Tellus Programme 2021

Geological Survey Ireland Programme Updates

Tellus Programme 2021

by Dr. Jim Hodgson, Senior Geologist & Tellus Programme

Manager at Geological Survey Ireland

The Tellus Programme, Geological Survey, Ireland’s ground and airborne geoscience data acquisition programme celebrates is tenth anniversary this year.

Since the initial survey of the border region in 2011-2012 we have continued to collect airborne geophysical and ground geochemical data and despite the ongoing difficulties of operating in a global pandemic this has continued in 2021. In fact, by the end of 2021, we should be close to 80% of the country covered by the airborne survey and soil samples collected from nearly 70%. 2021 saw the collection of soil samples across the Greater Dublin Area in a new urban sampling survey. Along with soil samples collected to help investigate the chemical signature across Dublin samplers also collected samples of vegetation. Research work by Trinity College Dublin’s Botany Department, plans to investigate the relationship between the chemistry of the soil and the vegetation and whether plants can be used to reduce contamination in some areas. Samplers also had the opportunity to meet with President Michael D. Higgins when they had to collect samples from the grounds of Áras an Uachtaráin. Regional sampling has continued in the southeast of Ireland with sample teams continuing to collect more soil. Despite the difficulties of the crew travelling to Ireland and undergoing mandatory quarantine, the airborne survey completed the A8 block over counties Kilkenny, Laois and Tipperary. It is planned to publish the data later this year. Ceasium 137 data also collected as part of the airborne survey has been extracted and merged together to show Caesium variations within the soil across the country. These new data will be available to download from the Tellus website from September 2021. The Terra Soil project in conjunction with Teagasc has also continued with the delivery of new analytical data from the Johnstown laboratories. This information will help in understanding both the chemistry and fertility of the soil. The Tellus team along side colleagues from the minerals programme have also been actively working on a mineral prospectivity mapping project in the northwest of Ireland. Geophysical data has been interpreted and nearly 125,000 geochemical measurements collected by exploration companies over the years have been digitised, this will help with developing a model for mineral prospectivity in the region. Research is also been carried out inverting the electromagnetic data, allowing resistivity cross-sections to be produced helping to map the thickness of gravel aquifers and depth to bedrock. None of the Tellus Programme would be possible without the dedication of Tellus team making sure the surveys continue even in the difficult circumstance caused by covid-19. Further information regarding the Tellus survey can be found at the project website www.tellus.ie

Figure 1: Tellus soil samplers meeting President Higgins at Áras an Uachtaráin. Photo credit: J. Hodgson Figure 2: A birds eye view from the survey aircraft over Block A8. Photo credit: Sander Geophysics Ltd.