Report
The conference, hosted at the University of St Andrews on 19–21 March 2014, followed the collaboration of a group of geologists working on the North Atlantic Craton, in association with The Mineralogical Society of Great Britain and Ireland. The event was held under the banner of the Cardiff and St. Andrews chapters of The Society of Economic Geologists and the students and staff of the Department of Earth & Environmental Sciences at the University of St Andrews, in conjunction with The British Geological Survey (BGS) and The Geological Survey of Denmark and Greenland (GEUS). The ambition of the meeting was to initiate and further trans-Atlantic collaboration in understanding the Archaean cratonic controls on ore-deposit formation.
The Archaean high-grade gneiss terrain of the NAC stretches from Labrador, Canada, through Greenland and into Scotland and many aspects of its geology are common across geographical and political boundaries. Acceleration in exploration efforts for various commodities across this region, particularly in Greenland, has highlighted the potential for its mineral resources. With these opportunities come unique challenges, not least in ‘unpicking’ the prolonged and complicated history of such ancient lithosphere. Successful exploration is increasingly reliant on ‘geology’ and ‘geological interpretation’ and less on straightforward and traditional prospecting techniques. The importance of a craton-specific approach to mineral exploration has been realised more recently.
New working collaborations have resulted from this meeting, bridging industry, academia and learned societies, and from across Europe, Greenland, Canada, US and Australia. Opportunities for current students in this field have also arisen directly from this meeting. For example, three student placements have been set up for Summer 2014 between two exploration companies and students of Exploration Geology at Cardiff University and members of the Cardiff SEG Chapter. Their work will be based in Greenland and Canada.
Mineralogical Magazine Special Issue
Several presentations at the meeting are being written up for publication in a thematic issue of Mineralogical Magazine, a journal of the Mineralogical Society of Great Britain & Ireland. These are to be submitted by 30 September 2014 with publication anticipated by early 2015.
Future Meetings
The 2014 NAC meeting hosted 85 international delegates from the US, Canada, Greenland, Denmark, Sweden, France, DRC, South Africa, Australia, and UK. Delegates represented various European, Canadian, American and Africa universities, as well as various geological surveys (BGS, GUES, BNP, USGS, Canadian Surveys) and 17 different exploration and mining companies, and consultancies. During the two day conference, 32 talks and 16 posters presented, alongside various industry and society stands. The post-conference field trip sold out 4 months in advance of the trip and received strong support. The trip was run for 17 delegates from various industry and academic backgrounds, guided by Kathryn Goodenough (BGS) and Hannah Hughes (Cardiff University).
Based on the success of this 2014 meeting, plans are ongoing for a similar meeting to take place in 2016 under the title of ‘NAC+’ and following on from the alliances in 2014 and in conjunction with new groups. As with the 2014 meeting, future meetings would not be restricted to the NAC itself, but also encompass the adjoining craton margins – areas which are prospective for a greater range of commodities. The current organizing committee of the 2014 meeting encourage potentially interested groups and individuals to get in contact via NACworkshop@gmail.com.
The organizers take this opportunity to formally thank the Department of Earth & Environmental Sciences at the University of St Andrews for hosting this event. They also thank the generous sponsors, both in industry and academia, for making the NAC Conference such as success.
- These include:
• Northern Shield Resources (headline industry sponsors) for sponsoring the Ni-Cu-PGE session and its refreshment breaks, the drinks and refreshments at the poster session, the conference dinner and ceilidh.
• The Mineralogical Society of Great Britain and Ireland for sponsoring keynote speakers. The Mineralogical Society’s Hallimond Lecturer at the conference was Dr Graham Begg.
• The Applied Mineralogy Group for sponsoring the keynote speaker of the Ni-Cu-PGE session, Prof Sarah-Jane Barnes.
• The Society of Economic Geologists for sponsoring the keynote speaker of the Au session, Prof Richard Goldfarb.
• Avannaa Resources for sponsoring the icebreaker reception.
• Midland Valley Exploration for sponsoring the poster board hire for the poster session.
• Aurum Global Exploration and Glasmin Resources for sponsoring the production of delegate packs and abstract volumes.
• The Mineral Deposits Studies Group for providing student bursaries.
Thanks to the following individuals who helped to make the conference a success:
Organising Committee: A. Finch, K. Goodenough, H. Hughes, J. Hughes, K. Murphy, D. Schlatter
Session chairs: N. Arndt, A. Finch, K, Goodenough, J. Kinnaird, D. Schlatter.
Venue assistance: M. Griffiths, M. Hughes, R. Rajendra, E. Hunt, M. Stacey, J. Watkins
Programme with links to presentations where available.
Session 1: Regional-scale controls and the geology of the NAC
Cratonic structure and regional controls on mineral systems (Hallimond Lecture)
G.C. Begg, J.M.A. Hronsky, S.Y. O’Reilly, W.L. Griffin and Lev Natapov
The North Atlantic Craton and its bounding terranes in Canada: tectonic framework and mineral potential
David Corrigan and Mary Sanborn-Barrie
Tectonic history and mineralisation in the North Atlantic Craton: A view from Scotland
Goodenough, K.M., Macdonald, J.M., Johnson, T.E., Hughes, H.S.R., Shaw, R.A. and Millar, L.
The oxidation state of the Archaean mantle: insights from the precise measurement of Fe+/ΣFe in Archaean chromitites
Hugh Rollinson, Jacob Adetunji, and Davide Lenaz
The geochemical composition of Archaean ultramafic, mafic and andesitic rocks of supracrustal and intrusive origins, SW Greenland – Geodynamic implications
Kristoffer Szilas
Proterozoic mafic dyke swarms of the Western North Atlantic Craton: Distribution, age, geochemical and paleomagnetic studies, and implications for Precambrian plate reconstructions and metallogeny
M.A. Hamilton, T. Sahin, M.K.M. Nilsson and K.L. Buchan
New insights on the evolution of the North Atlantic Craton from geochronology and isotope geochemistry of the Scourie dykes, NW Scotland.
Joshua H.F.L. Davies, Larry M. Heaman, Richard J. Stern, Xavier Rojas and Erin L. Walton
Geochemistry and U-Pb geochronology of mid-Proterozoic dyke swarms within the North Atlantic Craton, South Greenland
A. Bartels, M.B. Klausen, M.K.M. Nilsson and U. Söderlund
Session 2: Metallogeny of the NAC – general
Metallogeny of the North Atlantic Craton, Greenland
J. Kolb, B.M. Stensgaard and L. Bagas
How does nature make the perfect rare element deposit? Insights from the Gardar Province of Southern Greenland
Adrian A Finch, Jamie McCreath, Emma Hunt and Joshua Hughes
Incompatible element concentration within in the Late Gardar Southern Rift, South Greenland
B.G.J. Upton
Peralkaline magmatic layering: development of the eudialyte-rich Unit 0 marker horizon, Ilimaussaq Complex, S. Greenland
E.J. Hunt, A.A. Finch and C.H. Donaldson
Apatite and allanite-hosted REE mineralization at Hoidas Lake, Saskatchewan, Canada and implications for the melts/fluids responsible for REE deposition and remobilization
Krisztina Pandur, Kevin M. Ansdell and Daniel J. Kontak
Initial thoughts on the geology of the Aappaluttoq Ruby Deposit
Andrew J. Fagan and Lee A. Groat
Mantle metasomatism and the continental record
Chris Hawkesworth, Peter Cawood and Bruno Dhuime
Session 3: Metallogeny of the NAC – layered intrusions and Ni-Cu-PGE
Using the trace element contents of magmatic sulphide and oxide minerals in exploration for and exploitation of magmatic ore deposits
S.-J. Barnes, P. Page S.A.S. Dare and D. Savard
Understanding layered intrusions and their ore deposits: still many rivers to cross
W.D. Maier
Ni-Cu-PGE potential of the NAC
Nicholas Arndt and Alexander Sobolev
Seeing the Forest for the Trees: Using Geochemistry as a Vector in PGE Exploration along the Eastern Margin of the Superior Province, Canada
Ian C. Bliss and Christine Vaillancourt
The Maniitsoq Ni-Cu-Co-PGE project, Qeqqata Kommunia, southern West Greenland
John Pattison, Neil Richardson, Mark Fedikow, James Sparling and John Roozendaal
The Disko Island, West Greenland, Noril’sk Type Ni-Cu-PGE target; geological settings and analogies to a world class nickel camp
Pelle Gulbrandsen and Henrik Sabra
The Disko Island, West Greenland, Noril’sk Type Ni-Cu-PGE target; applied geophysical methods in deep and blink exploration targets
Henrik Sabra and Pelle Gulbrandsen
The potential for orthomagmatic Ni-Cu-PGE mineralisation in Western Scotland: observed controls and mechanims
Hannah S R Hughes, Iain McDonald, Adrian J Boyce and Andrew C Kerr
Freetown, a tear in the corner of the North Atlantic
J.F.W. Bowles,, I.C. Lyon, H.M. Prichard, J. Stewart, S. Süarez and D.J. Vaughan
Session 4: Metallogeny of the NAC – Gold & base metals
Targeting orogenic gold: What are the keys for exploration?
Richard J. Goldfarb (contact the author at goldfarb@usgs.gov for a copy of his presentation)
Intrusion Related Gold Systems in South Greenland – The Proterozoic Nanortalik Gold Belt
J.W. Hughes, D. Schlatter and O. Christiansen
Gold mineralisation and differences of associated hydrothermal alteration of Archaean gold prospects in SW Greenland
Denis M. Schlatter
A review of the Gairloch Cu-Zn-Au Deposit
W.J. Charter
Fluid flow on the Iapetus Suture: Timing and composition
B. Davidheiser-Kroll, D.F. Mark, L.E. Morgan and A.J. Boyce
Session 5: Exploration techniques
The past is the key to the future: insight gained through thinking about projects in their geodynamic context
G.R. Nicoll, G. Baines and J. Etienne
Constraining margin evolution with basic structural techniques
Tim Davis
Dragging exploration into the Quantum Age: using the ground penetrating abilities of a new coherent radiowave and microwave imaging spectrometer
G.C.Stove, J.McManus, M.J.Robinson, G.D.C. Stove
Poster presentations
The Amikoq PGE deposit – tectonic fragments of an Archaean layered mafic intrusion in the Fiskefjord region, southern West Greenland
Paul E.B. Armitage and I. McDonald
Towie, Aberdeenshire, Scotland, GreenOre Gold Plc
Gavin Berkenheger
A review of the Gairloch Cu-Zn-Au Deposit
W.J. Charter and A. Bevan
Crustal anatexis during granulite facies metamorphism in the central region of the Lewisian Complex
Sebastian Fischer, Timothy E. Johnson, Richard W. White and Michael Brown
Noble metal enrichment in the margin of the North Atlantic Craton: Impacts for Ni-Cu-PGE mineralisation in W Scotland
Hannah Hughes, I. McDonald, B.G.J. Upton and A.C. Kerr
Diamond exploration in West Greenland – The Qaamasoq Project
Josh Hughes, M.T. Hutchison and O. Christiansen
Aillikite – an unconventional diamond host rock and its importance in the ‘Greenland-Labrador-(Scotland?) Diamond Province’
Josh Hughes
GEUS Nuuk office
Majken Poulsen
How hot was the British Tertiary mantle plume? New constraints from high-Mg picrites on Skye and Rum
Holly Spice, Godfrey Fitton and Linda Kirstein
The Lost Gardar Intrusion: Critical metal exploration at the Paatusoq Syenite Complex, South East Greenland
Mark Stacey, A.A. Finch, J.W. Hughes, and O. Christiansen
Ellesmerian-aged reactiviation of soft-sediment deformation structures in the evaporite-rich Cape Webster formation of the Franklinian Basin, Washington Land, North Greenland,
Alan Vaughan
The Kangerluarsuk SEDEX lead-zonc project, West Greenland
Pelle Gulbrandsen and Henrik Sabra
Motzfeldt: A multi-element package opportunity in the Gardar Province, South Greenland
Helen Salmon and Natasha Henwood
The Melville Bugt Dyke Swarm, Greenland: Precise U-Pb ages, Geochemistry, Paleomagnetism and Possible Late Paleoproterozoic Connections with Baltica or Amazonia
M.A. Hamilton, M.K.M. Nilsson and H.C. Halls
Fieldtrip to the Scottish Highlands
The margin of the North Atlantic Craton is exposed in the Northern Highlands of Scotland, north of the Great Glen Fault. This area is internationally famous for its evidence for large-scale horizontal shortening of continental crust, as a result of the piling-up of thrust sheets along the Moine Thrust Zone during the Caledonian Orogeny, in the early Silurian. The Moine Thrust Zone extends for around 200 km, from Loch Eriboll to the Isle of Skye, and the total displacement along its component thrusts was at least 100 km.
To the west of the thrust zone lies the Caledonian Foreland, with superb exposures of Archaean gneisses that were reworked in several Palaeoproterozoic events; the Lewisian Gneiss Complex. The complex also includes some Palaeoproterozoic island arc terranes. The gneisses are overlain by Proterozoic and early Palaeozoic sedimentary rocks, which are undeformed in the Foreland, but have been affected by thrusting within the Moine Thrust Zone. The Proterozoic successions include the Mesoproterozoic Stoer Group and the Neoproterozoic Torridon Group, the latter comprising several kilometres of red sandstones that form some of the most distinctive mountains in the area. These are overlain by a Cambro-Ordovician succession dominated by quartz arenites in its lower part (the Ardvreck Group) and dolomitic limestones of the Durness Group in its upper part.
To the east of the Moine Thrust Zone are deformed and metamorphosed Neoproterozoic sedimentary rocks of the Moine Supergroup. These contain several inliers of Archaean gneiss that show affinities to the Lewisian Gneiss Complex of the Foreland, and indicate that the basement of the North Atlantic Craton continues beneath this part of Northern Scotland.
During and immediately after Silurian thrusting the region was intruded by a suite of alkaline igneous intrusions, which includes some of the most potassic igneous rocks in Britain, as well as the only known British carbonatite. These intrusions include the Loch Borralan and Loch Loyal syenite complexes, which are of particular interest for their contents of some critical metals such as the Rare Earth Elements.
The excursion focused on the areas of most potential for understanding mineralisation within the North Atlantic Craton, namely the Lewisian Gneiss Complex and the alkaline intrusive complexes.
The trip was led by Kathryn Goodenough and Hannah Hughes and had 19 other participants.
