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OUGS Mainland Europe |
Greenland |
Kalaallit Nunaat |
OUGS Mainland Europe organised a field trip to Greenland 27 July—6 August 2003
See the day-by-day pictorial report from the field trip
The information and the links on this page were especially relevant for this trip, but hopefully also interesting in their own right.
Acknowledgements
This trip would never have been possible without the help and support from:
Geological Survey of Denmark and Greenland (GEUS)
Geological Museum (under Copenhagen University)
Their sites offer a wealth of geological and tourist information on Greenland.
Studied
area (South Greenland)
Ilímaussaq and other intrusions in the Gardar province (See below under 'Geology') plus the area of the Nalunaq gold deposit (see below under 'Economic Geology'). Hotel accommodation in Narsarsuaq, Narsaq and Nanortalik.
At www.greenland-guide.gl you can download the tourist brochure South Greenland, Adventures of a world apart (in PDF format).
Trip
Reports
Copenhagen Geological Museum organized a similar field trip in 2001 for mainly Austrian geologists. Read the trip report from one of the participants. Unfortunately it is yet unfinished, but even so it already has a lot of information and pictures.
During the last two weeks of July 2001, Ron Peterson, professor of mineralogy at Queen’s University, led an expedition to the Ilímaussaq and Igaliko alkaline intrusions in the Julianehåb district, South Greenland. Julian Gray wrote a report in the January Newsletter of the Mineralogical Association of Canada. The Newsletter in PDF format can be downloaded at the Mineralogical Association of Canada.
MinerShop had a tour to the Ilímaussaq complex in 2002 in search of fluorescent minerals. Their trip report shows that it was not in vain.
Geology
(South Greenland)
South Greenland and the Ketilidian orogeny
For an overview of the geology of South Greenland we recommend to read the first couple of pages of Stendal et al. 1993 (see more under "publications") - free pdf download. On page 66 there is a very useful geological map. We are going to visit some of the Gardar intrusions, shown in the centre of the map. In Garde et al. 1998 (see more under "publications) - free pdf download - there is a similar map. If you are not interested in text, you can download a simplified geological map of South Greenland (also from GEUS).
There is so much information on the Internet about the geology of the area and
the minerals to be found in the Gardar Province, that we cannot name
it all. The following very short description should give you an idea of what
to search for.
The Ketilidian orogeny of southern Greenland
can be divided from north to south into:
- An Archean/Ketilidian border zone
A zone in which the crystalline rocks of the Archaean craton are unconformably overlain by Ketilidian (paleoproterozoic) supracrustal rocks. - A granite batholith
A major polyphase pluton, referred to as the Julianehåb batholith. The Julianehåb batholith is interpreted as the root zone of an original island arc along the edge of the Archean continent to the north. It is almost entirely composed of calc-alkaline plutonic rocks. The emplacement took place between 1850–1800 Ma. - Ketilidian rocks
Weathering and erosion products from the (later) uplifted and unroofed batholith were deposited in a fore-arc basin to the south of the arc as sand near to the arc and clay further out into the basin (with a hypothetical oceanic plate situated further south). These former sediments are now found in- a zone of psammitic rocks (metamorphosed feldspathic sandstones and siltstones and minor conglomerates) and
- a zone of pelitic rocks ((meta-) siltstones and mudstones ) at the south tip of Greenland.
- Compression, deformation, (migmatizing) and folding of these rocks took place during the Ketilidian orogeny from 1855 to 1725 million years ago ending with intrusion of volcanic rocks (rapakivi granites - and rapakivi-textured quartz monzonites and granodiorites) in the sandstone and shale zones. Four episodes of deformation have been recognised in the Ketilidian fore arc.The intrusions of the rapakivi suite cover ca. 3000 km2. They were emplaced between 1755–1723 Ma.
The Gardar Province (within the batholith zone)
In the Mesoproterozoic a few hundred million years later a period of intensive magmatism and widespread faulting about 1300 to 1120 million years ago related to a continental rifting process gave rise to about ten major and some minor intrusions (Ivigtut, Igaliko, Ilímaussaq, Narsaq, Tugtutôq, Nunarssuit, Motzfeldt, Puklen, Kungnat, Ikka-Grønnedal to name some of the more important). This post-orogenic Gardar rifting has probably no causal connection with the Ketilidian orogeny, and the (ENE-WSW) rift failed. The intrusions are highly significant in economic terms, and a fantastic el dorado for mineral hunters. More than 200 different minerals have been found in the area (that OUGSME visited) around Narsaq, Igaliku and Narsarsuaq. Many of those were found and described here for the first time, and some are found nowhere else.
On the Ilímaussaq Peninsula the intrusions not only cut through the metamorphic-migmatite-granitoid basement (Julianehåb batholith), but also through outliers of sandstone (continental, i.e. fluvial and aeolian) and volcanic rocks (lavas) of the Eriksfjord Formation (1600-1310 Ma). (The Eriksfjord Formation is also present on the south side of Tunugdliarfik - NB Eriksfjord is the Danish name for the fjord Tunugdliarfik). The thickest preserved Eriksfjord succession on the Ilímaussaq Peninsula comprises about 3400m. Map showing the Eriksfjord Formation can be found on page 48 in a document on mining in Greenland from New Millennium Resources. The whole document can be downloaded as a large pdf file - 1.7 MB.
The Ilímaussaq Complex
For a geological map of the complex see the Newsletter
(pdf) of the Mineralogical Association of Canada, number 66, January 2002, p.
8, where there also is a map (bottom left) showing the main localities that
the OUGSME is going to visit in 2003.
The Ilímaussaq alkaline complex is the type locality for agpaitic nepheline
syenites (called agpaitic after the town of Agpat at the eastern rim of the
complex, at Tunulliarfik Fjord).
It is the youngest of a number of syenitic bodies in the Gardar province and
contains several types of syenite.
It is Greenland's most prolific mineral producer in terms of the number of mineral
species. It has produced over two hundred different minerals and a number
of them are exclusive to this locality.
The complex was intruded in three stages.
Intrusions rich in alkali metals, especially sodium, and poor in silica and
aluminium formed many of the unique assemblages of minerals.
The complex is exceptionally rich in lithium (Bailey et al 1993) giving rise
to many interesting Li minerals. There is also a high level of certain trace
elements, especially Zr, Nb and the rare earth elements.
The Ilímaussaq alkaline intrusion show cryptorhytmic and macrorhytmic
layering (Bailey 1995). Note that the two probably most famous layered intrusions
in the world, Skaergaard (the classic example) and Bushveld are basic.
Economic
Geology (South Greenland)
Simplified geological map of South Greenland also showing abandoned and planned mines.
From http://www.geus.dk/minex/mx_theme-uk.htm there is free download of a Theme Magazine: "Geology and Ore" (Gold mineralisation and gold potential in South Greenland) and three Fact Sheets on Greenland Mineral Resources: 1: Gold mineralisation and gold potential in South Greenland, 2: Early mining activities in South Greenland, 3: Deposits of speciality metals in South Greenland
MINEX is a newsletter to the international mining industry with up-to-date geoscientific and legislatory information about Greenland published by GEUS in co-operation with Bureau of Minerals and Petroleum , Greenland Government. MINEX is available free of charge and the newest issues (since November 1998) are available online (PDF).
Abandoned mines:
Kvanefjeld, abandoned uranium mine lies in the northern part of Ilímaussaq complex. 1958-1980 on a pilot scale.
Ivittuut, the world famous and unique cryolite mine (abandoned). 3.7 Mt of ore mined from 1854 to 1987
The Josva copper mine. 1904-1915.
King Frederik VII Mine (near Julianehåb), abandoned copper (and silver)mine. Only 18 tons of ore were mined 1851, 1912.
Amitsoq, abandoned graphite mine. 1911-1924. Graphite schists in folded migmatite zone.
New mine:
Nalunaq, new gold mine. After successful test mining (see under publications) the mine construction is expected to start in the first half of 2003 (by Crew Development Corporation: Nalunaq Gold Mine A/S Incorporated). Nalunaq Gold Project
Deposits with a potential (in particular in the peralkaline/alkaline intrusions in the Gardar province):
Tantalum (used in capacitors used in mobile phones and other electronics). Motzfeldt complex. Angus & Ross, the Cambridgeshire mining company, is interested according to this article in Business Weekly.
Niobium. Motzfeldt and Kvanefjeld.
Zirconium at Kangerluarsuk (agpaitic rocks within the Ilímaussaq intrusion)
Yttrium at Kangerluarsuk (agpaitic rocks within the Ilímaussaq intrusion)
Rare Earth Elements.
Beryllium at Kvanefjeld.
Further links to Mines & Mining in Greenland
Publications
Relevant publications in the Geology of Greenland Survey Bulletin:
Stendal et al (1996): "Mafic igneous rocks and mineralisation in the Paleoproterozoic Ketilidian orogeny, South-East Greenland: project SUPRASYD 1996" in Geology of Greenland Survey Bulletin Volume 176 (in the series Review of Greenland Activities). Free downloadable pdf file from GEUS.
Adam A. Garde, John Grocott and Ken J.W.McCaffrey (1998): "New insights on the north-eastern part of the Ketilidian orogeny in South-East Greenland" in Geology of Greenland Survey Bulletin Volume 183 (in the series Review of Greenland Activities). Free downloadable pdf file from GEUS.
Mogens Lind, Lotte Kludt and Brian Ballou (2001): "The Nalunaq gold Prospect, South Greenland: test mining for feasibility studies" in Geology of Greenland Survey Bulletin Volume 189 (in the series Review of Greenland Activities). Free downloadable pdf file from GEUS.
Volume 190 (2002). The Ilímaussaq alkaline complex, South Greenland:
status of mineralogical research with new results.
Edited by Henning Sørensen. This volume is not free on line. The content
is described at the
GSB 190 site.
Relevant publications in the Bulletin of the Geological Society of Denmark:
Bailey, J. C., Bohse, H., Gwozdz, R. and Rose-Hansen, J. 1993.
Li in minerals from the Ilímaussaq alkaline intrusion, South Greenland.
Bulletin of the Geological Society of Denmark, vol. 42, pp. 288-299. Copenhagen
1993-12-30.
Bailey, J. C. 1995:
Cryptorhythmic and macrorhythmic layering in aegirine lujavrite, Ilímaussaq
alkaline intrusion, South Greenland.
Bulletin of the Geological Society of Denmark, vol. 42, pp.l-16. Copenhagen
1995-10-31.
Finch, A.A., Mansfeld, J. & Andersen, T. 2001-06-28:
U-Pb radiometric age of Nunarsuit pegmatite, Greenland: constraints on the timing
of Gardar magmatism.
Bulletin of the Geological Society of Denmark, Vol. 48, pp. 1-7, Copenhagen.
Abstract
Rose-Hansen, J. & Sørensen, H. 2001-06-28:
Minor intrusions of peralkaline microsyenite in the Ilímaussaq
alkaline complex, South Greenland.
Bulletin of the Geological Society of Denmark, Vol. 48, pp. 9-29, Copenhagen.
Abstract
Clemmensen, L. B. 1988:
Aeolian morphology preserved by lava cover, the Precambrian Mussartût
Member, Eriksfjord Formation, South Greenland.
Bulletin of the Geological Society of Denmark, Vol. 37, pp. 105-116, Copenhagen,
October 14th, 1988.
Relevant publication in Canadian Journal of Earth Sciences
Garde et al. 2002:
The Ketilidian orogeny of South Greenland: geochronology, tectonics, magmatism,
and fore-arc accretion during Paleoproterozoic oblique convergence, Vol.39 (2002)
pp.765–793. Abstract
Relevant publications in Journal of the Geological Society:
Chadwick, B., Garde, A., Grocott, J. , McCaffrey, K, & Swager, C. 2002. Mid-crustal partitioning and attachment during oblique convergence in an arc system, Palaeoproterozoic Ketilidian orogen, southern Greenland. Journal of the Geological Society 159 , 247-261.
Grocott, J., Garde, A.A., Chadwick, B., Cruden, A.R. & Swager, C. 1999.
Emplacement of rapakivi granites by floor depression and roof uplift in the
Palaeoproterozoic Ketilidian orogen, South Greenland. Journal of the Geological
Society 156, 15-24. Abstract.
Map
Sydgrønland, Sheet 1 of Geological map of GREENLAND 1:500 000, Grønlands Geologiske Undersøgelse (now part of GEUS) 1990, with descriptive text by Kalsbeek et al.
Book references
Anthony Hall, Igneous Petrology, Longman Scientif & Technical,
1987. ISBN 0-582-30174-2.
A textbook on igneous petrology. Ilímaussaq treated on pp. 240 and 421-3.
Alan M. Goodwin, Principles of Precambrian Geology, Academic
Press, 1996, reprinted 2000. ISBN 0-12-289770-6.
Comprehensive guide to Precambrian geology. Simplified geological map of South
Greenland p. 63. Ketilidian Mobile Belt p. 135. Gardar Province p. 189.
Museum
collections
Geologisk Museum, Copenhagen, Denmark.
Naturhistorisches Museum, Vienna, Austria. Exhibition of samples collected by the friends of the museum ("Freunde des Naturhistorischen Museums") during their field trip to the same area in 1999.
If you know of any other relevant public exhibition, please let us know.
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Last modified on Monday, May 09, 2005 at 08:34
