Tellus Newsletter No. 1 October 2015

22nd October 2015

Welcome to the first edition of Tellus News!

Tellus is a ground and airborne geoscience mapping programme, collecting chemical and geophysical data that will inform the management of Ireland’s environment and natural resources.

Now into its fifth year, Tellus has been established as a programme area in the Geological Survey of Ireland following two successful surveying phases in the border and north midlands regions. GSI has developed a strategy to advance Tellus surveying nationally on a phased basis, beginning with a three‐year plan to complete 50% of the country by the end of 2017. The phases have been developed with significant input from a wide range of stakeholders. Read on for progress with airborne and ground based surveying so far this year.

Results from the Tellus airborne survey of the North Midlands region have been released by the Geological Survey of Ireland. The magnetic map shown here is part of a suite of geophysical data now freely available at www.tellus.ie.

Tellus North Midlands survey data has landed

The Tellus North Midlands airborne survey covering the counties of Longford, Roscommon and Westmeath completed is final flight in April 2015. The survey was carried out by CGG Airborne based in Johannesburg, South Africa. In total 32,142 line km were flown by two Cessna 208B aircraft. The small aircraft with their trailing EM receiver birds were a regular site in the midlands region over the first part of the year.

On 21st September, magnetic intensity, gamma-ray spectrometry and time-domain electromagnetic conductivity data from this survey were released to view and download free of charge. Data highlights include prominent bands of highly magnetic volcanic rocks several kilometres deep near Strokestown Co. Roscommon, which are associated with a major geological fault that can be traced through Ireland to Scotland. These structures are known to be important in the development of mineral deposits and their location will be of considerable interest to exploration companies.

The maps also reveal new detail of 330 million-year-old volcanoes on the Westmeath/Offaly border south of Mullingar which appear in the new airborne geophysical data as a cluster of small magnetic bodies. The findings from the north midlands are significant as they contribute another piece to the jigsaw of Ireland’s first seamless cross-border geoenvironmental mapping project which began in 2007. The ‘buried volcanoes’ of the midlands seemed to capture the public’s imagination – the Tellus team was very busy for the few days following the data release doing radio interviews and press features on these exciting findings.

Surveying during the winter meant cold but often spectacular flying conditions

If you would like to be added to the mailing list to recieve notifications for data releases, please email tellus@gsi.ie.

Tellus geophysical survey of eastern Ireland almost complete

Sander Geophysics De havilland Twin Otter DHC-6

The latest phase of the airborne survey, which took off from Weston airport on 29th June 2015, is almost complete. The survey sees the return of the Canadian firm Sander Geophysics and their Twin-Otter De Havilland aircraft which successfully completed the Tellus Border survey in 2011-2012. This twin engine fixed wings aircraft uses a frequency domain Electromagnetic method housed in the pods on the wingtips with a magnetometer located in the rear tail stinger and 3 gamma-ray spectrometer crystal packs housed inside. The aircraft flies at a survey altitude of 60m in counties Offaly, Kildare, Meath, North Wicklow and rural Dublin (see Figure below showing extent of the survey area). In total over 32,000km will be flown – progress stands at 99% complete following some clear autumn conditions.

Due to the low flying altitude of the aircraft and heavy concentration of equine industries in the area, an extensive public outreach programme has been undertaken. This has included the distribution of 268,000 fliers to households, an information line, radio interviews, articles in local newspapers, postering of local shops and visits to studs farms and interested parties.
Stay tuned for news of survey completion and announcement of results in spring 2016.

Soil sampling in Co. Mayo, September 2015. Image courtesy John Cullen/OCAE Consultants Ltd.

Soil Sampling Survey underway across the West of Ireland

Tellus has started a soil survey of counties Mayo and Galway and northern county Clare, continuing on from the soil survey of the North Midlands in 2014.

A team of agricultural scientists will be traversing the highlands and lowlands of the West of Ireland over the autumn and winter months as the Tellus survey continues its roll-out across Ireland.

On 29th September 2015, a team of eight agricultural scientists from OCAE Consultants Ltd started working in pairs collecting soil samples using a hand auger from every 4km² of land on behalf of Tellus. In total, 2,000 different locations over a 7,500 km² expanse of land will be visited by the team during this important ground survey phase. The soil samples will be analysed for a broad range of elements, revealing natural and man-made influences on the soil geochemistry of the area in great detail.

The team started in the Westport area but they will prioritise higher ground such as the Nephin Beg mountain range, and the Sheefry Hills in Mayo and the Twelve Bens in Connemara, as well as coastal areas to make the most of the autumn daylight hours. Already the teams have been working in some spectacular terrain and have been making the most of the crisp autumn weather conditions.

Research call announced – closing date 3rd November

The Geological Survey of Ireland has published a new call for short research projects across all areas of activities including Tellus, to close on 3rd November 2015 at 5pm.

It is open to both industry and researchers with a lead partner on the island of Ireland. Proposals are invited for projects less than one year duration, to a maximum value of €25,000.

Application is via a simple template here. Enquiries to research@gsi.ie.

Modelled on previous successful research programmes by INFOMAR and Tellus, this call invites researchers to propose projects across diverse themes. Example topics for investigation of Tellus data are given here. Selected previous Tellus research topics are summarised on the research page.

Research highlights

Following the release of Tellus Border data in October 2013, Tellus scientists have been busy interpreting the wealth of information now available on the physical and chemical makeup of earth materials in the border region of Ireland. Expert interpretation is feeding into updated bedrock maps, radon modelling and geochemical research in-house in GSI and GSNI.

Cobalt deficiency in soils – communicating uncertainty

Map on verbal probability scale (with probabilities indicated as percentages) of the probability that local topsoil Co and Mn concentrations would indicate a risk of Co deficiency.

British Geological Survey researchers Drs Murray Lark, Louise Ander and Mark Cave recently collaborated with the GSI geochemistry team to publish an

open-access paper on mapping trace element deficiency in sheep[1] using Tellus Border topsoil data. BGS Environmental Statistician Dr Murray Lark presented the project at the European Geosciences Union congress in Vienna in April 2014, as part of a session focussing on the communication of uncertain information in earth sciences. The research employs the Intergovernmental Panel on Climate Change verbal scale for communicating uncertain predictions, which has proved useful for communicating the uncertainty encountered when mapping the natural variability of geochemical data. Research outputs include maps of predicted cobalt deficiency in the border region of Ireland based on soil cobalt and manganese concentrations, along with verbal and numerical probabilities that a deficiency is indicated.

[1] Lark, R.M., Ander, E.L., Cave, M.R., Knights, K.V., Glennon, M.M. and Scanlon, R.P. (2014) Mapping trace element deficiency by cokriging from regional geochemical soil data: a case study on cobalt for grazing sheep in Ireland. Geoderma, 226–227, 64–78.

Re-mapping the Moffat Shales using Tellus geophysics

Moffat Shales

The Sandbian to Llandovery Moffat Shale Group is a deep marine mudstone sequence that forms the base of successive thrust slices of metasedimentary rocks in the accretionary Longford – Down terrane. Mapping the distribution of the shales, therefore, indicates the regional structure of the terrane, with application to mineral prospectivity and understanding the closure history of Iapetus at the Laurentian margin. Moffat shale horizons produce a strong conductivity signal in the Tellus and Tellus Border airborne geophysical survey data (Floyd, 2013; Beamish et al., 2010). We have combined interpretation of the EM data with re-examination of GSI 19th century 6″ field sheets and core drilling to re-map the Moffat shales in Co. Monaghan. Drilling of a blind anomaly proved the efficacy of the method. The re-mapping has identified a revised distribution of Moffat shales and therefore of the tract-bounding faults, including identifying a new structural panel.

Highly conductive horizons in drill core, identified with a simple multi-meter, are being examined to identify the lithological control on conductivity. A reasonable correlation between very dark coloured shale and a lower resistance exists, suggesting that the Tellus conductivity survey may be responding to the presence of graphite

The image displays the new distribution of the Moffat shale horizons and test drill holes, overlain on the Tellus EM data.

References:

Beamish, D., Kimbell, G.S., Stone, P. & Anderson, T.B. 2010. Regional conductivity data used to reassess Lower Palaeozoic structure in the Northern Ireland sector of the Southern Uplands–Down–Longford terrane. Journal of the Geological Society, London, 167, 649–657.

Floyd, J.D. 2013. A comparison and appraisal of the geological correlation between the Southern Uplands and Down-Longford sub-terranes.

Don’t forget to register for Geoscience 2015

The annual seminar of the Geological Survey of Ireland will be held on 4th November 2015 at the Clayton Hotel, Ballsbridge. The event will feature a session on Tellus, which will give updates on surveying progress this year, plans for 2016-2017 and latest news of data releases.

Please register here. Registration is free of charge.

Tellus Border Post-project evaluation

In April 2014 PA Consulting Group was appointed as independent evaluators of the Tellus Border project, looking at the operations and outputs of the project from start to finish. For the Special EU Programmes Body, Tellus Border’s funding body, the post project evaluation is an essential part of ensuring value for money when it comes to publicly funded science projects. The evaluation was also an opportunity for the project team to hear from stakeholders about the usefulness of the project outputs in several different sectors including mineral exploration, environmental management, research and public health.

The Tellus team welcomed the findings of the evaluation, which highlighted that the project

· Was delivered on time and on budget, ensuring value for public money by exceeding the requirements of the €5m EU INTERREG-funded grant;

· Generated easily accessible, world-leading geoenvironmental data for a wide range of stakeholders in the public and private sectors who are deriving significant value from the data.

This valuable feedback has already helped to shape plans for future Tellus surveys which will build on the findings of Tellus Border and further develop impactful benefits from the data.