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Theme Magazines and Fact Sheets
EXPLORATION AND MINING IN GREENLANDGreenland Mineral Resources
Fact Sheet No. 12
Download pdf-file go_fs12.pdf (~450 kbyte). Requires pdf-reader, Acrobat GSview or similar
More than sixty intrusions
are catalogued in the Pala-
eogene East Greenland vol-
canic rifted margin. The plu-
tonic suites range from ultra-
mafic to Felsic, from depleted
basaltic to highly alkaline,
and from upper crustal intru-
sions to subvolcanic centres
and breccia pipes with relat-
ed epithermal vein systems.
The East Greenland magma-
tism lasted from 61 to 13 Ma.
The Skaergaard PGE and gold
deposit and the Malmbjerg
molybdenum deposit have
the potentials to become
world-class size deposits.
are catalogued in the Pala-
eogene East Greenland vol-
canic rifted margin. The plu-
tonic suites range from ultra-
mafic to Felsic, from depleted
basaltic to highly alkaline,
and from upper crustal intru-
sions to subvolcanic centres
and breccia pipes with relat-
ed epithermal vein systems.
The East Greenland magma-
tism lasted from 61 to 13 Ma.
The Skaergaard PGE and gold
deposit and the Malmbjerg
molybdenum deposit have
the potentials to become
world-class size deposits.
Geological setting
The East Greenland volcanic rift-
ed margin developed prior to,
during and after the onset of
seafloor spreading in the North
Atlantic. Picritic to basaltic lavas
erupted locally in Palaeocene
(61-57 Ma) and were followed
(57-54 Ma) by up to 5 km thick
regional flood basalts. They cor-
relate across the early North
Atlantic to the Faeroe Islands.
The flood basalts are preserved
between Kangerlussuaq and
Kangertittivaq (Scoresby Sund)
(68º-70ºN) and are in part overlain by 13 Ma old lavas.
Major sill complexes occur in Mesozoic to Paleocene
sediments below the lavas.
ed margin developed prior to,
during and after the onset of
seafloor spreading in the North
Atlantic. Picritic to basaltic lavas
erupted locally in Palaeocene
(61-57 Ma) and were followed
(57-54 Ma) by up to 5 km thick
regional flood basalts. They cor-
relate across the early North
Atlantic to the Faeroe Islands.
The flood basalts are preserved
between Kangerlussuaq and
Kangertittivaq (Scoresby Sund)
(68º-70ºN) and are in part overlain by 13 Ma old lavas.
Major sill complexes occur in Mesozoic to Paleocene
sediments below the lavas.
A large domal uplift at the Kangerlussuaq Triple
Junction (68ºN) signals the surfacing of the proto-
Iceland plume (55-50 Ma). Early picritic lavas show
strong similarities to Hawaiian lavas, whereas overlying
flood basalts show Icelandic affinities. The transition
from intra plate to spreading ridge magmatism is illus-
trated.
Junction (68ºN) signals the surfacing of the proto-
Iceland plume (55-50 Ma). Early picritic lavas show
strong similarities to Hawaiian lavas, whereas overlying
flood basalts show Icelandic affinities. The transition
from intra plate to spreading ridge magmatism is illus-
trated.
Coast-parallel dyke swarm systems are mostly related to
magmatic centres dotted along the East Greenland
coast. Deep erosion has exposed a number of magmatic
centres south of 68ºN. They comprise early gabbros -
magmatic centres dotted along the East Greenland
coast. Deep erosion has exposed a number of magmatic
centres south of 68ºN. They comprise early gabbros -
some with PGE and Au mineralisations, followed by
intermediate tOFelsic intrusions. The volcanic cover is
not preserved north of Kangertittivaq (70º-73ºN), where
large sill and dyke systems intrude Mesozoic sediments.
A large number of mostly felsic intrusives and subvol-
canic complexes are exposed between 72º and 74ºN -
some with molybdenum accumulation. Flood basalts to
the north of the province (73º-75ºN) host a few subvol-
canic basaltic tOFelsic complexes, and underlying sedi-
ments are intruded by picrite and basalt sills.
intermediate tOFelsic intrusions. The volcanic cover is
not preserved north of Kangertittivaq (70º-73ºN), where
large sill and dyke systems intrude Mesozoic sediments.
A large number of mostly felsic intrusives and subvol-
canic complexes are exposed between 72º and 74ºN -
some with molybdenum accumulation. Flood basalts to
the north of the province (73º-75ºN) host a few subvol-
canic basaltic tOFelsic complexes, and underlying sedi-
ments are intruded by picrite and basalt sills.
Inland intrusions and lavas are alkaline to highly alka-
line, and include a carbonatite-bearing complex.
line, and include a carbonatite-bearing complex.
The mineral potential of the
Palaeogene intrusions,
East Greenland
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Gardiner complex
Hold with Hope
Shannon Ø
Myggbukta
Kap Parry
Kap Simpson
Antarctic Havn
Malmbjerg
Lilloise intrusion
Miki Fjord
Kap Edvard Holm
Nugalik/Kruuse Fjord
Imilik/Kialineq
Kap Gustav Holm
Sulugssut complex
Werner Bjerge
Kangertittivaq
Iceland
Inland Ice
100 km
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Kangerdlugssuaq intrusion
Borgtinderne
Sødalen
Skaergaard intrusion
Flammefjeld
Tasiilaq
Illoqqortoormiit/
Scoresbysund
Scoresbysund
Daneborg
Palaeogene intrusive centre
pre-Cretaceous
Major fault
Cretaceous/Palaeogene sediments
Palaeogene basalt
Map of the Palaeogene igneous province, East Greenland.
Exploration history
Regional mapping (1930s
to 1960) north of Kanger-
tittivaq (70º-73ºN) led to
the discovery of several
mineral occurrences. The
Malmbjerg molybdenum
deposit was the main focus
between 1950 and 1970
and again from 2004.Other
felsic intrusions along the
East Greenland coast show
signs of mineral accumulation, but no other
deposits are located. Veins with precious and base
metals are common.
to 1960) north of Kanger-
tittivaq (70º-73ºN) led to
the discovery of several
mineral occurrences. The
Malmbjerg molybdenum
deposit was the main focus
between 1950 and 1970
and again from 2004.Other
felsic intrusions along the
East Greenland coast show
signs of mineral accumulation, but no other
deposits are located. Veins with precious and base
metals are common.
The Blosseville Coast (70º-68ºN) has been subject-
ed to prospecting, whereas the intrusions at
Kangerlussuaq (68ºN) and down the coast to
Nugalik (67ºN) have seen more exploration (1969-
1971 and 1987-1991). The Skaergaard intrusion
was in 1987 recognised as a large low-grade pla-
tinum group element-gold deposit. Many other
mafic intrusions show signs of platinum group ele-
ment mineralisation.
ed to prospecting, whereas the intrusions at
Kangerlussuaq (68ºN) and down the coast to
Nugalik (67ºN) have seen more exploration (1969-
1971 and 1987-1991). The Skaergaard intrusion
was in 1987 recognised as a large low-grade pla-
tinum group element-gold deposit. Many other
mafic intrusions show signs of platinum group ele-
ment mineralisation.
Main types of mineralisation
Stratiform PGE and Au mineralisation:
The Skaergaard intrusion (68ºN) and the Kap Ed-
vard Holm Complex (68ºN) are representatives.
Mineralisation is caused by sulphur saturation.
Drilling in the Skaergaard intrusion has delineated
a 1500 million tonne multi-element (platinum
group elements, gold, silver, copper, titanium and
vanadium) occurrence. The Kap Edvard Holm com-
plex contains large tonnage, low-grade, stratiform
platinum group element-gold horizon.
The Skaergaard intrusion (68ºN) and the Kap Ed-
vard Holm Complex (68ºN) are representatives.
Mineralisation is caused by sulphur saturation.
Drilling in the Skaergaard intrusion has delineated
a 1500 million tonne multi-element (platinum
group elements, gold, silver, copper, titanium and
vanadium) occurrence. The Kap Edvard Holm com-
plex contains large tonnage, low-grade, stratiform
platinum group element-gold horizon.
Contact-related and sulphide-hosted PGE
mineralisation:
The Kruuse Fjord intrusion (67ºN) and Miki Fjord
Macrodyke (68ºN) are representatives. Sulphides
rich in platinum group elements are found at con-
tacts between mafic intrusive units and basement
or other intrusive units.
mineralisation:
The Kruuse Fjord intrusion (67ºN) and Miki Fjord
Macrodyke (68ºN) are representatives. Sulphides
rich in platinum group elements are found at con-
tacts between mafic intrusive units and basement
or other intrusive units.
Porphyry-related molybdenum mineralisation:
The Malmbjerg granite stock and Flammefjeld are
representatives of classic stockwork type occur-
rences in late felsic intrusions. The Malmbjerg
deposit is estimated to contain approx. 200 million
tonnes of ore grade. Flammefjeld has not been
drilled. Several other intrusions show molybdenum
mineralisation and may offer potentials.
The Malmbjerg granite stock and Flammefjeld are
representatives of classic stockwork type occur-
rences in late felsic intrusions. The Malmbjerg
deposit is estimated to contain approx. 200 million
tonnes of ore grade. Flammefjeld has not been
drilled. Several other intrusions show molybdenum
mineralisation and may offer potentials.
Epithermal vein deposits:
Faults and shear zones along the East Greenland
coast and related to intrusive complexes, which
host hydrothermal gold, silver, and lead bearing
systems. The Tågegang vein and Yellow Zone,
both related to the Flammefjeld molybdenum
prospect (68ºN), have high lead, gold and silver
contents. Large regional, fault controlled, hydro-
thermal vein systems are only sporadically tested.
Faults and shear zones along the East Greenland
coast and related to intrusive complexes, which
host hydrothermal gold, silver, and lead bearing
systems. The Tågegang vein and Yellow Zone,
both related to the Flammefjeld molybdenum
prospect (68ºN), have high lead, gold and silver
contents. Large regional, fault controlled, hydro-
thermal vein systems are only sporadically tested.
The inland carbonatite-bearing ultramafic alkaline
Gardiner complex hosts large ring dyke systems
composed of apatities with> 50% apatite.
Gardiner complex hosts large ring dyke systems
composed of apatities with> 50% apatite.
Based on research and exploration carried out so
far, it is generally accepted that the Skaergaard
platinum group element and gold deposit as well
as the Malmbjerg molybdenum deposit have the
potential to become world-class size deposits.
far, it is generally accepted that the Skaergaard
platinum group element and gold deposit as well
as the Malmbjerg molybdenum deposit have the
potential to become world-class size deposits.
Geological Survey of Denmark
and Greenland (GEUS)
Øster Voldgade 10
DK-1350 Copenhagen K
Denmark
Tel: (+45) 38 14 20 00
Fax.: (+45) 38 14 20 50
E-mail: geus@geus.dk
Internet: www.geus.dk
Bureau of Minerals and Petroleum
(BMP)
Government of Greenland
P.O. Box 930
DK-3900 Nuuk
Greenland
Tel: (+299) 34 68 00
Fax.: (+299) 32 43 02
E-mail: bmp@gh.gl
Internet: www.bmp.gl
Author:
T. F.D. Nielsen
Editor: K.Secher
Layout: GEUS, Grafisk
© GEUS 2005
ISSN: 1602-8171
Key references
Escher, A. & Watt, W.S. (eds): Geology of Greenland, Copenhagen:
Grønlands Geologiske Undersøgelse, 603 pp.
Harpøth, O., Pedersen, J.L., Schønwandt, H.K. & Thomassen, B.
1986: The mineral occurrences of central East Greenland.
Meddelelser om Grønland, Geoscience
17
, 139 pp.
Nielsen, T.F.D. 1987: Tertiary alkaline magmatism in East Greenland:
a review. In: Fitton, J.G. & Upton, B.G.J. (eds): Alkaline igneous
rocks. Special Publication, Geological Society of London
30
489-515.
Nielsen, T.F.D. 2002: Palaeogene intrusions and magmatic com-
plexes in East Greenland, 66º to 75ºN. Danmarks og Grønlands
Geologiske Undersøgelse Rapport 2002/
113
, 249 pp.
Nielsen, T.F.D., Andersen, J.C.Ø. & Brooks, C.K. 2005: The Platinova
Reef of the Skaergaard intrusion. In: Mungall, J.E. (ed.):
Exploration for Platinum-Group Element Deposits. MAC Short
Course
35
, 431-455. Ottawa: Mineralogical Association of
Canada.
Skaergaard intrusion. A view to Gabbrofjeld and
Wagertoppen (1200m) in the northern part of the
intrusion.
Wagertoppen (1200m) in the northern part of the
intrusion.
Last modified: January 17, 2006
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