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Theme Magazines and Fact Sheets
Download "Geology and Ore no. 6, February 2006" go06.pdf (~2.6 mb)
Exploration and Mining in Greenland
GEOLOGY AND ORE
No. 6 - February 2006
The mineral potential
of the East Greenland
Palaeogene intrusions
of the East Greenland
Palaeogene intrusions
Flood basalts, dyke swarms and intru-
sive complexes characterise the outer
coastal area of East Greenland. They
are all part of the Palaeogene volcanic
rifted margin that formed prior to,
during, and after the onset of seafloor
spreading in the North Atlantic. The
magmatic province stretches from c.
66°N to c. 75°N, a distance of c. 1,300
km. The magmatism lasted for about
50 million years, from 61 to 13 Ma.
More than sixty Palaeogene intrusions
are recorded. The plutonic suites
range in composition from ultramafic
tOFelsic and from depleted basaltic to
highly alkaline, and in form from
upper crustal intrusions to subvolcanic
centres and breccia pipes with related
epithermal vein systems.
sive complexes characterise the outer
coastal area of East Greenland. They
are all part of the Palaeogene volcanic
rifted margin that formed prior to,
during, and after the onset of seafloor
spreading in the North Atlantic. The
magmatic province stretches from c.
66°N to c. 75°N, a distance of c. 1,300
km. The magmatism lasted for about
50 million years, from 61 to 13 Ma.
More than sixty Palaeogene intrusions
are recorded. The plutonic suites
range in composition from ultramafic
tOFelsic and from depleted basaltic to
highly alkaline, and in form from
upper crustal intrusions to subvolcanic
centres and breccia pipes with related
epithermal vein systems.
Due to its remoteness, severe climate
and rugged topography, the East Green-
land Palaeogene province remains
vastly underexplored. In spite of this,
two world-class deposits the Malm-
bjerg porphyry-molybdenum deposit
and the Skaergaard mafic intrusion-
hosted stratiform PGE-gold deposit are
known from this region that offers a
promising potential for mineral de-
posits of similar or other types.
land Palaeogene province remains
vastly underexplored. In spite of this,
two world-class deposits the Malm-
bjerg porphyry-molybdenum deposit
and the Skaergaard mafic intrusion-
hosted stratiform PGE-gold deposit are
known from this region that offers a
promising potential for mineral de-
posits of similar or other types.
Flood basalts
Picritic to basaltic lavas erupted locally in
the Paleocene (6157 Ma) and they were
followed (5754 Ma) by regional flood
basalts up to 5 km thick. They correlate
across the North Atlantic to the Faeroe
Islands. The flood basalts are preserved
between Kangerlussuaq and Kangertit-
tivaq (Scoresby Sund, 68°70°N) and are
in part overlain by 13 Ma old lavas. With
remnants of the flood basalt province
present between 66° and 75°N, the East
Greenland flood basalt province ranks
with provinces like Parana and Deccan as
the largest on Earth. The main volume of
the Paleocene (6157 Ma) and they were
followed (5754 Ma) by regional flood
basalts up to 5 km thick. They correlate
across the North Atlantic to the Faeroe
Islands. The flood basalts are preserved
between Kangerlussuaq and Kangertit-
tivaq (Scoresby Sund, 68°70°N) and are
in part overlain by 13 Ma old lavas. With
remnants of the flood basalt province
present between 66° and 75°N, the East
Greenland flood basalt province ranks
with provinces like Parana and Deccan as
the largest on Earth. The main volume of
basalts extruded between 57 and 54 mil-
lion years ago.
lion years ago.
Early picrite lavas show strong similari-
ties to Hawaiian lavas whereas overlying
flood basalts show Icelandic affinities. A
transition from plume-generated, intraplate
products to spreading ridge magmatism is
illustrated. A triple junction, plume-type
melts and a large domal uplift suggest that
the early Iceland plume surfaced in the
Kangerlussuaq area (68°N).
flood basalts show Icelandic affinities. A
transition from plume-generated, intraplate
products to spreading ridge magmatism is
illustrated. A triple junction, plume-type
melts and a large domal uplift suggest that
the early Iceland plume surfaced in the
Kangerlussuaq area (68°N).
Sill complexes
Major sill complexes in sedimentary basins
pre-date the lavas. The two main areas of
sills are in the Cretaceous to Paleocene
Kangerlussuaq Basin (69°N) and the
Palaeozoic to Paleocene basins to the
north of Kangertittivaq (70°N). The
sediments range from arkoses and
conglomerates to pyritic black
shales in the Kangerlussuaq
Basin, and from conglomerates,
associated clastic sediments
and shales to dolostones and
gypsum beds in areas north
of Kangertittivaq. Aggregate
sill thicknesses of 1 km are
observed, and individual
sills can be more than 100
m thick. The sills are
dominantly basaltic, but
range from picritic to
highly evolved
basaltic composi-
tions.
pre-date the lavas. The two main areas of
sills are in the Cretaceous to Paleocene
Kangerlussuaq Basin (69°N) and the
Palaeozoic to Paleocene basins to the
north of Kangertittivaq (70°N). The
sediments range from arkoses and
conglomerates to pyritic black
shales in the Kangerlussuaq
Basin, and from conglomerates,
associated clastic sediments
and shales to dolostones and
gypsum beds in areas north
of Kangertittivaq. Aggregate
sill thicknesses of 1 km are
observed, and individual
sills can be more than 100
m thick. The sills are
dominantly basaltic, but
range from picritic to
highly evolved
basaltic composi-
tions.
Dyke swarms
Large-volume, coast-parallel dyke swarm
systems, some resembling sheeted com-
plexes, formed in the flexured continental
margin and in relationship to magmatic
centres. The dyke swarms strike for hun-
dreds of kilometres and represent intru-
sion from c. 60 to at least 35 Ma. The
dyke swarms are dominated by tholeiitic
basalts, but range from picritic tholeiites
to highly alkaline nephelinites and carbon-
atites. All magma types found in flood
basalts and central complexes are repre-
sented in the dyke swarms.
systems, some resembling sheeted com-
plexes, formed in the flexured continental
margin and in relationship to magmatic
centres. The dyke swarms strike for hun-
dreds of kilometres and represent intru-
sion from c. 60 to at least 35 Ma. The
dyke swarms are dominated by tholeiitic
basalts, but range from picritic tholeiites
to highly alkaline nephelinites and carbon-
atites. All magma types found in flood
basalts and central complexes are repre-
sented in the dyke swarms.
2
GEOLOGY AND ORE 6 / 2006
The mineral potential of the
East Greenland Palaeogene
intrusions
East Greenland Palaeogene
intrusions
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
Gardiner complex
Hold with Hope
Kap Broer Ruys
Shannon Ø
Myggbukta
Kong Oscar Fjord
Wiedemann Fjord
Kangerlussuaq
Mesters Vig
Kap Parry
Traill Ø
Kap Simpson
Oksehorn, Theresabjerg
Malmbjerg
Lilloise intrusion
Miki Fjord
Kap Edvard Holm
Nordre Aputiteq
Nugalik/Kruuse Fjord
Imilik/Kialineq
Kap Gustav Holm
Sulugssut complex
Werner Bjerge
K angertittivaq
Iceland
I n l AND I c e
100 km
I
I
Kangerlussuaq intrusion
Borgtinderne
Sødalen
Skaergaard intrusion
Flammefjeld
Bl
os
se
vi
lle
K
ys
t
Tasiilaq
Illoqqortoormiit/
Scoresbysund
Scoresbysund
Daneborg
Palaeogene intrusive centre
pre-Cretaceous
Major fault
Cretaceous/Palaeogene sediments
Palaeogene basalt
69°
66°
72°
16°
75°
32°
24°
16°
24°
Map of the Palaeogene East Greenland igneous
province.
province.
Intrusions and central complexes
Central complexes are dotted along the
East Greenland coast. South of Kanger-
lussuaq (68°N), uplift followed by deep
erosion has exposed a suite of magmatic
centres. They comprise early gabbros
some with PGE and gold mineralisation
followed by intermediate tOFelsic intru-
sions, including monzonites, syenites and
granites. One complex is nephelinitic with
carbonatite affinities.
East Greenland coast. South of Kanger-
lussuaq (68°N), uplift followed by deep
erosion has exposed a suite of magmatic
centres. They comprise early gabbros
some with PGE and gold mineralisation
followed by intermediate tOFelsic intru-
sions, including monzonites, syenites and
granites. One complex is nephelinitic with
carbonatite affinities.
Twenty-eight intrusions and complexes
are recorded in the Kangerlussaq area
(68°N). They range from ultramafic plugs,
replenished ocean floor-type gabbro com-
plexes (Kap Edvard Holm, c. 50 Ma),
strongly fractionated closed system gab-
bros (Skaergaard, c. 54 Ma), dioritic intru-
sions and undersaturated and oversaturat-
ed syenites and granites (Kangerlussuaq,
c. 50 Ma), to carbonatite-bearing nephe-
linitic complexes (Gardiner, c. 54 Ma). The
most voluminous intrusions and complex-
es are the syenitic Kangerlussuaq intrusion
(c. 700 km
(68°N). They range from ultramafic plugs,
replenished ocean floor-type gabbro com-
plexes (Kap Edvard Holm, c. 50 Ma),
strongly fractionated closed system gab-
bros (Skaergaard, c. 54 Ma), dioritic intru-
sions and undersaturated and oversaturat-
ed syenites and granites (Kangerlussuaq,
c. 50 Ma), to carbonatite-bearing nephe-
linitic complexes (Gardiner, c. 54 Ma). The
most voluminous intrusions and complex-
es are the syenitic Kangerlussuaq intrusion
(c. 700 km
2
) and the PGE-bearing Kap
Evdard Holm gabbro complex (>
400 km
2
).
To both of these are related suites of
smaller and peripheral intrusions, includ-
ing the subvolcanic Flammefjeld complex
with molybdenum mineralisation at the
margin of the Kangerlussuaq intrusion.
The PGE- and gold-mineralised Skaergaard
intrusion (c. 70 km
ing the subvolcanic Flammefjeld complex
with molybdenum mineralisation at the
margin of the Kangerlussuaq intrusion.
The PGE- and gold-mineralised Skaergaard
intrusion (c. 70 km
2
) is the best-known
intrusive complex in East Greenland.
A second large group of intrusive com-
plexes is located in the Kong Oscar Fjord
area (72°N). These are large, dominantly
felsic intrusions but magnetic anomalies
suggest that most are underlain by mafic
complexes. The roof zone of a gabbro
intrusion is the oldest part of the Werner
Bjerge complex which is dominated by
area (72°N). These are large, dominantly
felsic intrusions but magnetic anomalies
suggest that most are underlain by mafic
complexes. The roof zone of a gabbro
intrusion is the oldest part of the Werner
Bjerge complex which is dominated by
3
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Aerial view of flood basalts intruded by syenite at Borgtinderne. The peaks are c. 2500 m a.s.l.
200 km
32°
24°
16°
75°
16°
72°
69°
66°
24°
32°
69°
72°
75°
Kangertittivaq
Inland Ice
A. 24
A. 24
Exposed tholeiitic flood basalts
(Schematic)
Supposed original tholeiitic
flood basalt area
Exposed alkaline basalts
Area invaded by tholeiitic sills
Exposed centre, single or multiple
Not exposed centre
Gabbroic, "tholeiitic"
Syenitic Granitic
Nepheline syenite
Alkaline basic to salic complex
Alkaline dike swarms
(Schematic)
Supposed original tholeiitic
flood basalt area
Exposed alkaline basalts
Area invaded by tholeiitic sills
Exposed centre, single or multiple
Not exposed centre
Gabbroic, "tholeiitic"
Syenitic Granitic
Nepheline syenite
Alkaline basic to salic complex
Alkaline dike swarms
Thematic map of the Palaeogene East Green-
land igneous province. A. 24: magnetic ocean
floor anomaly.
land igneous province. A. 24: magnetic ocean
floor anomaly.
alkali syenites and granites and a large
nepheline-syenite body. This complex
shows molybdenum mineralisation, best
known from the Malmbjerg porphyry-
nepheline-syenite body. This complex
shows molybdenum mineralisation, best
known from the Malmbjerg porphyry-
molybdenum deposit hosted by a small
granitic stock.
granitic stock.
A suite of mainly granitic and syenitic
intrusions is exposed north-east of the
Werner Bjerge complex. The suite includes
the roof sections of two large intrusive
centres on the south shore of Kong Oscar
Fjord (Oksehorn and Theresabjerg) and
two major centres on the eastern head-
lands of Traill Ø (Kap Simpson and Kap
Parry). The most northerly intrusions are
found on Hold with Hope (73°30'N), and
comprise the roof of a large basaltic com-
plex at Myggbugta and felsic sheets at
Kap Broer Ruys.
the roof sections of two large intrusive
centres on the south shore of Kong Oscar
Fjord (Oksehorn and Theresabjerg) and
two major centres on the eastern head-
lands of Traill Ø (Kap Simpson and Kap
Parry). The most northerly intrusions are
found on Hold with Hope (73°30'N), and
comprise the roof of a large basaltic com-
plex at Myggbugta and felsic sheets at
Kap Broer Ruys.
Mineral exploration
Commercial mineral exploration in East
Greenland was triggered by the 1948 gale-
na-find at Mesters Vig, which led to min-
ing of the Blyklippen Pb-Zn vein deposit
between 1956 and 1962. Nordisk Mine-
selskab A/S was established in 1952 to
investigate and mine Blyklippen, but also
to explore a large concession area between
70°N and 74° 30'N amounting to 100,000
km
Greenland was triggered by the 1948 gale-
na-find at Mesters Vig, which led to min-
ing of the Blyklippen Pb-Zn vein deposit
between 1956 and 1962. Nordisk Mine-
selskab A/S was established in 1952 to
investigate and mine Blyklippen, but also
to explore a large concession area between
70°N and 74° 30'N amounting to 100,000
km
2
. The company performed mineral
exploration in the period 195284, and
found a large number of mineral occur-
rences. Most effort was put into the inves-
found a large number of mineral occur-
rences. Most effort was put into the inves-
4
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Palaeogene dyke swarm intruded into Precambrian gneiss, south of Kruuse Fjord. The cliff is c. 80 m
high.
high.
Vivid colours of argillic alteration and iron hydroxides in pyro-
clastic rocks, Kap Simpson complex. The peak is c. 700 m a.s.l.
clastic rocks, Kap Simpson complex. The peak is c. 700 m a.s.l.
tigation of the Malmbjerg molybdenum
deposit between1955 and 1981 and part-
ly in joint ventures with AMAX Inc. Other
Palaeogene intrusions north of 70°N were,
however, also reconnoitred. In 197071, the
company prospected in the region between
67° and 69°N and detected the first indi-
cations of molybdenum and gold in the
Kangerlussuaq area. In 1982 detailed sur-
face investigations were accomplished at
the Flammefjeld molybdenum prospect.
deposit between1955 and 1981 and part-
ly in joint ventures with AMAX Inc. Other
Palaeogene intrusions north of 70°N were,
however, also reconnoitred. In 197071, the
company prospected in the region between
67° and 69°N and detected the first indi-
cations of molybdenum and gold in the
Kangerlussuaq area. In 1982 detailed sur-
face investigations were accomplished at
the Flammefjeld molybdenum prospect.
In the period 1986 to 1996, Platinova
A/S operated with various joint venture
partners in the region between 67° and
69°N. The main effort was the investiga-
tion of the noble metal potential of the
Skaergaard intrusion but the Kap Edvard
Holm intrusion and other intrusions of this
southern region were also investigated to
various degrees. A recent player is Galahad
Gold Plc, which through its subsidiary Skaer-
gaard Minerals Corp. investigated the Skaer-
gaard deposit in 200304, and, through
the subsidiary International Molybdenum
Plc, the Malmbjerg deposit in 2005.
partners in the region between 67° and
69°N. The main effort was the investiga-
tion of the noble metal potential of the
Skaergaard intrusion but the Kap Edvard
Holm intrusion and other intrusions of this
southern region were also investigated to
various degrees. A recent player is Galahad
Gold Plc, which through its subsidiary Skaer-
gaard Minerals Corp. investigated the Skaer-
gaard deposit in 200304, and, through
the subsidiary International Molybdenum
Plc, the Malmbjerg deposit in 2005.
Mineral occurrences
Significant mineral occurrences in the
Palaeogene East Greenland province are
given in table-form below. In order to
illustrate the province's mineral potential,
some of the best investigated occurrences
are described in the following sections.
Palaeogene East Greenland province are
given in table-form below. In order to
illustrate the province's mineral potential,
some of the best investigated occurrences
are described in the following sections.
Malmbjerg porphyry Mo deposit
Malmbjerg is located in the Werner Bjerge
massif at 72°N. It hosts a porphyry-molyb-
denum deposit of the Climax-type, discov-
ered in 1954 during systematic mapping
by members of the Danish East Greenland
Expeditions. Investigations in 195561 by
Nordisk Mineselskab A/S, and in 1962 by
a Nordisk Mineselskab/AMAX Inc. joint
venture, involved the excavating of three
adits totalling 1,329 m, from where 146
holes were drilled, totalling some 22,000
m. An ore body of 119 Mt grading 0.25%
MoS
massif at 72°N. It hosts a porphyry-molyb-
denum deposit of the Climax-type, discov-
ered in 1954 during systematic mapping
by members of the Danish East Greenland
Expeditions. Investigations in 195561 by
Nordisk Mineselskab A/S, and in 1962 by
a Nordisk Mineselskab/AMAX Inc. joint
venture, involved the excavating of three
adits totalling 1,329 m, from where 146
holes were drilled, totalling some 22,000
m. An ore body of 119 Mt grading 0.25%
MoS
2
at a cut-off of 0.17% MoS
2
was
defined, but not found profitable with the
molybdenum price of the time. In 2004,
Galahad Gold Plc acquired the property,
spurred by a dramatic rise in the molybde-
num price.
molybdenum price of the time. In 2004,
Galahad Gold Plc acquired the property,
spurred by a dramatic rise in the molybde-
num price.
5
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Traditional transportation: M/S "Ejnar Mikkelsen" off Kap Edvard Holm, 1971.
Modern transportation: unloading of a Twin Otter STOL aircraft at the Sødalen airstrip, 2000.
Type Commodities
Deposit/prospect
Showing/indication
Porphyry Mo,
W
Malmbjerg
Mellempas
Flammefjeld
Kap
Simpson
Epithermal veins
Au, Ag, Pb,
Blyklippen
Amdrup Fjord
Zn, Cu
Mesters Vig
Coastal dyke swarm
Kap Simpson
Others
Mafic intrusion-hosted,
Pd, Pt, Au,
Skaergaard intrusion Nordre Aputiteq
stratiform (Skaergaard type)
Ti, Fe, V
Kap Edvard Holm
Mafic intrusion-hosted,
Pt, Pd, Cu, Ni
Miki Fjord macrodyke
contact-related (Noril'sk type?)
Kruuse Fjord
Peralkaline rock-associated
Nb, Ta, Be,
Werner Bjerge
Zr, Y, REE
Kap Simpson
Kangerlussuaq
intrusion
Carbonatite-associated
Apatite, Nb, Fe
Gardiner complex
Volcanic redbed
Cu
Wiedemann Fjord
Overview of mineral occurrences in the East Greenland Palaeogene magmatic province
The Malmbjerg porphyry-molybdenum
deposit is associated with a 25.7 Ma,
composite, alkali granite stock intruded
into Carboniferous sandstones. The stock
is part of the intrusive Werner Bjerge alka-
line complex and consists of three litho-
logical units: perthite granite with a
quartz-feldspar porphyry roof phase, a
heterogeneous porphyritic aplite and por-
phyritic granites. Molybdenite mineralisa-
tion occurs in a 700 x 700 x 150 m invert-
ed bowel-shaped body located mainly in
the perthite granite and its porphyritic
roof phase. Molybdenite occurs in veinlets
forming a stockwork of mutually offset-
ting veins. In addition, Mo-W-bearing
greisen mineralisation occurs as flat-lying
veins, up to one metre thick; minor base
metal veins occur distally. Pronounced
alteration is associated with the minerali-
sation, both inside, below and above the
stockwork molybdenum mineralisation.
composite, alkali granite stock intruded
into Carboniferous sandstones. The stock
is part of the intrusive Werner Bjerge alka-
line complex and consists of three litho-
logical units: perthite granite with a
quartz-feldspar porphyry roof phase, a
heterogeneous porphyritic aplite and por-
phyritic granites. Molybdenite mineralisa-
tion occurs in a 700 x 700 x 150 m invert-
ed bowel-shaped body located mainly in
the perthite granite and its porphyritic
roof phase. Molybdenite occurs in veinlets
forming a stockwork of mutually offset-
ting veins. In addition, Mo-W-bearing
greisen mineralisation occurs as flat-lying
veins, up to one metre thick; minor base
metal veins occur distally. Pronounced
alteration is associated with the minerali-
sation, both inside, below and above the
stockwork molybdenum mineralisation.
International Molybdenum Plc (Inter-
Moly) conducted a major field programme
in 2005, that included 4,900 m of under-
ground drilling (31 holes) and 1,776 m
channel sampling along the existing adits.
The programme also comprised geotechnical
drilling, bulk-sampling, site studies for pro-
cessing facilities, environmental studies and
a full engineering study to determine the
feasibility of moving the Malmbjerg deposit
into commercial production. Based on the
2005 results and historical data, a mineral
resource estimate was announced by Inter-
Moly in November 2005. It shows meas-
in 2005, that included 4,900 m of under-
ground drilling (31 holes) and 1,776 m
channel sampling along the existing adits.
The programme also comprised geotechnical
drilling, bulk-sampling, site studies for pro-
cessing facilities, environmental studies and
a full engineering study to determine the
feasibility of moving the Malmbjerg deposit
into commercial production. Based on the
2005 results and historical data, a mineral
resource estimate was announced by Inter-
Moly in November 2005. It shows meas-
6
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
WNW
ENE
Schuchert
Gletscher
Gletscher
Talus
Arcturius Adit
Porphyritic aplite
Perthite granite
Quartz - feldspar porphyry roof phase
of perthite granite
of perthite granite
Late Palaeozoic sediments
0.17% MoS
2
cut-off
High silica zone
Biotite - magnetite - quartz zone
0
100 m
Vertical section through the Malmbjerg ore body. After Harpøth et al. (1986).
Malmbjerg drill cores in InterMoly's 2005 camp.
Typical stockwork molybdenum mineralisation in the Schuchert adit,
Malmbjerg.
Malmbjerg.
Ø
st
re
G
let
sc
he
r
72°N
Mellempas
Schucher
t Gletscher
Ar
cturus Gletsch
er
Sirius Gletscher
24°W
Aldebaran G
letsc
her
M
el
le
m
gl
et
sc
h
er
Mo deposit
CarboniferousTriassic sediments
5 km
Basic complex
Alkali granite
Alkali syenites
Acid volcanics
Nepheline syenites
Malmbjerg granite stock
Geological map of the
Werner Bjerge alkaline com-
plex. Simplified after Bearth
(1959).
Werner Bjerge alkaline com-
plex. Simplified after Bearth
(1959).
ured and indicated resources of 217 Mt at
a grade of 0.20 % MoS
a grade of 0.20 % MoS
2
using a 0.12 %
cut-off grade, including a higher-grade zone
of 33.8 Mt at a grade of 0.28 % MoS
of 33.8 Mt at a grade of 0.28 % MoS
2
,
above a cut-off of 0.25 %. This resource
estimate will form the basis for determina-
tion of the mineable reserves in a feasibility
study that is under preparation.
estimate will form the basis for determina-
tion of the mineable reserves in a feasibility
study that is under preparation.
Flammefjeld Mo prospect
Flammefjeld is situated at the margin of
the c. 50 Ma old Kangerlussuaq intrusion
(68°N). The presumed youngest intrusive
rocks comprise the 39.6 Ma subvolcanic
Flammefjeld complex that intruded into
quartz syenites at the contact between
the Kangerlussuaq intrusion and satellite
intrusions. The Flammefjeld complex is a
500 x 800 m composite breccia pipe
intruded by quartz-feldspar porphyries and
it is surrounded by a halo of hydrothermal
alteration displaying vivid yellow and red
oxidation colours, and distal hydrothermal
veins. The name Flammefjeld means `flame
mountain'. The igneous breccias are of
various types, of which one is clearly intru-
sive. The quartz-feldspar porphyries occur
the c. 50 Ma old Kangerlussuaq intrusion
(68°N). The presumed youngest intrusive
rocks comprise the 39.6 Ma subvolcanic
Flammefjeld complex that intruded into
quartz syenites at the contact between
the Kangerlussuaq intrusion and satellite
intrusions. The Flammefjeld complex is a
500 x 800 m composite breccia pipe
intruded by quartz-feldspar porphyries and
it is surrounded by a halo of hydrothermal
alteration displaying vivid yellow and red
oxidation colours, and distal hydrothermal
veins. The name Flammefjeld means `flame
mountain'. The igneous breccias are of
various types, of which one is clearly intru-
sive. The quartz-feldspar porphyries occur
as breccia fragments, as a major intrusive
body and as late dykes.
body and as late dykes.
Until now, only surface investigations
have been carried out on Flammefjeld. These
include geological mapping and sampling,
and geochemical surveys using rock chip
samples and stream sediments. The exis-
tence of a major stockwork molybdenum
mineralisation below Flammefjeld is indi-
cated by the geochemical distribution of
molybdenum and tungsten, by the patterns
of wall-rock alteration (quartz-sericitic, pyritic
and argillic), and by the occurrence of stock-
work-type molybdenite mineralisation in
breccia fragments. Analyses of ten minera-
lised breccia fragments range from 651 to
6,847 ppm MoS
include geological mapping and sampling,
and geochemical surveys using rock chip
samples and stream sediments. The exis-
tence of a major stockwork molybdenum
mineralisation below Flammefjeld is indi-
cated by the geochemical distribution of
molybdenum and tungsten, by the patterns
of wall-rock alteration (quartz-sericitic, pyritic
and argillic), and by the occurrence of stock-
work-type molybdenite mineralisation in
breccia fragments. Analyses of ten minera-
lised breccia fragments range from 651 to
6,847 ppm MoS
2
with an average of 2,826
ppm. The proposed conceptual model en-
visages a blind Climax-type porphyry-moly-
bdenum deposit situated 400600 m below
Flammefjeld. The ore body is inverted-saucer
shaped with a diameter of 800 m, a thickness
of 200 m and a grade of up to 0.5% MoS
visages a blind Climax-type porphyry-moly-
bdenum deposit situated 400600 m below
Flammefjeld. The ore body is inverted-saucer
shaped with a diameter of 800 m, a thickness
of 200 m and a grade of up to 0.5% MoS
2
.
Mesters Vig Pb-Zn veins
Epithermal lead-zinc veins are abundant
over some 300 km
over some 300 km
2
in the Upper Carbon-
iferous Lower Permian clastic sediments
of the Mesters Vig area (72°N). Two major
vein zones are associated with the border
faults of a 4 x 12 km graben with a throw
of c. 1 km but other veins occur outside
the graben. The vein mineralogy is domi-
nated by quartz, baryte, galena and spha-
lerite with minor calcite, pyrite and chal-
copyrite, and traces of tetrahedrite. Galena
and sphalerite occur as massive lenses or
disseminated; the Pb/Ag ratio varies from
2,000 to 10,000. Wall-rock alteration
comprises mainly silicification and kaolini-
sation of the sandstone host. A vertical
zonation involving upwards enrichments
from quartz to baryte and from copper
through zinc to lead is indicated in some
of the veins, but no regional zonational
pattern is evident. The mineralisation is
assumed to be related to the intrusion of
the Werner Bjerge alkaline complex and is
thus of Palaeogene age. The richest of the
veins, the Blyklippen lead-zinc deposit,
was mined between 1956 and 1962 by
Nordisk Mineselskab A/S. Total production
was 544,600 tons ore grading 9.3% Pb,
9.9% Zn and 15 ppm Ag.
of the Mesters Vig area (72°N). Two major
vein zones are associated with the border
faults of a 4 x 12 km graben with a throw
of c. 1 km but other veins occur outside
the graben. The vein mineralogy is domi-
nated by quartz, baryte, galena and spha-
lerite with minor calcite, pyrite and chal-
copyrite, and traces of tetrahedrite. Galena
and sphalerite occur as massive lenses or
disseminated; the Pb/Ag ratio varies from
2,000 to 10,000. Wall-rock alteration
comprises mainly silicification and kaolini-
sation of the sandstone host. A vertical
zonation involving upwards enrichments
from quartz to baryte and from copper
through zinc to lead is indicated in some
of the veins, but no regional zonational
pattern is evident. The mineralisation is
assumed to be related to the intrusion of
the Werner Bjerge alkaline complex and is
thus of Palaeogene age. The richest of the
veins, the Blyklippen lead-zinc deposit,
was mined between 1956 and 1962 by
Nordisk Mineselskab A/S. Total production
was 544,600 tons ore grading 9.3% Pb,
9.9% Zn and 15 ppm Ag.
7
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Malmbjerg, seen from the south, positioned between Schuchert Gletscher (left) and Arcturus Gletscher (right).
Amdrup Fjord Au-Ag-base
metal veins
metal veins
Epithermal base-metal veins with signifi-
cant gold-silver concentrations occur in
both syenitic and gneissic parts of the area
north of Amdrup Fjord within a distance
cant gold-silver concentrations occur in
both syenitic and gneissic parts of the area
north of Amdrup Fjord within a distance
of 5 km from Flammefjeld. Forty veins
have been discovered and cursorily investi-
gated. Most have widths in the cmdm
range, but a few vein systems have widths
in the metre range (up to 30 m), and can
be followed over distances of several hun-
dred metres. The veins are typically locat-
have been discovered and cursorily investi-
gated. Most have widths in the cmdm
range, but a few vein systems have widths
in the metre range (up to 30 m), and can
be followed over distances of several hun-
dred metres. The veins are typically locat-
ed along cross-cutting mafic dykes and
developed as breccia fillings and crustifica-
tions of epithermal character, often dis-
playing vuggy and colloform structures
(cockade structures). Gangue minerals are
quartz, Ca-Mg-Mn-Fe-carbonates includ-
ing rhodochrosite, and occasionally fluo-
rite and baryte. Galena is the most com-
mon ore mineral, followed by pyrite and
sphalerite. Copper minerals (chalcopyrite
and tetrahedrite) are less common, and
arsenopyrite occurs sporadically. Gold
developed as breccia fillings and crustifica-
tions of epithermal character, often dis-
playing vuggy and colloform structures
(cockade structures). Gangue minerals are
quartz, Ca-Mg-Mn-Fe-carbonates includ-
ing rhodochrosite, and occasionally fluo-
rite and baryte. Galena is the most com-
mon ore mineral, followed by pyrite and
sphalerite. Copper minerals (chalcopyrite
and tetrahedrite) are less common, and
arsenopyrite occurs sporadically. Gold
8
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Flammefjeld seen from south-east with the Kangerlussuaq intrusion in the background.
Cut surface of igneous breccia from the Flamme-
fjeld complex. The large granitic fragment with
stockwork molybdenum mineralisation runs
0.45% MoS
fjeld complex. The large granitic fragment with
stockwork molybdenum mineralisation runs
0.45% MoS
2
.
Søndre Syenitgletscher
Amdrup Fjord / Atterteq
0.3/-
1.4/191
1.5/127
1.0/1193
7.5/70
6.0/104
0.6/-
2.2/213
0.2/-
0.3/56
-/169
-/55
-/65
1.0/-
-/309
-/58
0.9/-
68°15'
Vein-type mineralisation with strike
direction indicated
direction indicated
0.1/75
Max. ppm Au/Ag
Glacier
Palaeogene Flammefjeld complex
Palaeogene Kangerlussuaq intrusion
Archaean crystalline basement
Glacier
Palaeogene Flammefjeld complex
Palaeogene Kangerlussuaq intrusion
Archaean crystalline basement
Contour interval 100 m
Flammefjeld
32°20'
68°15'
32°20'
2 km
1
0
Simplified geological map of the Amdrup Fjord area. Maximum gold and silver values are indicated
where Au> 0.1 ppm and Ag> 50 ppm. From Thomassen & Krebs (2001).
where Au> 0.1 ppm and Ag> 50 ppm. From Thomassen & Krebs (2001).
occurs as electrum in association with the
sulphide minerals. The sulphides occur as
massive lenses and irregular seams of cm-
thickness, and disseminated, but total sul-
phide concentrations rarely exceed 1%
over the full width of the veins. Wall-rock
alteration comprises silicification, carbon-
atisation, kaolinisation, sericitisation and
propylitisation.
sulphide minerals. The sulphides occur as
massive lenses and irregular seams of cm-
thickness, and disseminated, but total sul-
phide concentrations rarely exceed 1%
over the full width of the veins. Wall-rock
alteration comprises silicification, carbon-
atisation, kaolinisation, sericitisation and
propylitisation.
Maximum recorded gold values are 1
ppm Au over 5 m in chip samples and
38.4 ppm Au from float. Maximum silver
values are 531 ppm Ag over 2 m in chip
samples, and 1,193 ppm Ag in grab sam-
ples. The Ag/Au ratio is about 200. The
relative concentrations of the base metals
are Pb> Zn> Cu, and the mineralisation
is also characterised by relative high man-
ganese concentrations, and occasionally
elevated arsenic, antimony, molybdenum
and bismuth. Although veins are distrib-
uted over a vertical distance of 800900
m, no general hydrothermal zoning cen-
tred on Flammefjeld has been observed,
apart from proximal copperdistal lead-
zinc indicated in some veins. This may be
due to insufficient data or to telescoping
of ore zones. The mineralisation appears
to be epithermal gold-silver veins of low-
sulphidation type and a genetic relation-
ship with a porphyry-type molybdenum
deposit below Flammefjeld has been pro-
posed.
38.4 ppm Au from float. Maximum silver
values are 531 ppm Ag over 2 m in chip
samples, and 1,193 ppm Ag in grab sam-
ples. The Ag/Au ratio is about 200. The
relative concentrations of the base metals
are Pb> Zn> Cu, and the mineralisation
is also characterised by relative high man-
ganese concentrations, and occasionally
elevated arsenic, antimony, molybdenum
and bismuth. Although veins are distrib-
uted over a vertical distance of 800900
m, no general hydrothermal zoning cen-
tred on Flammefjeld has been observed,
apart from proximal copperdistal lead-
zinc indicated in some veins. This may be
due to insufficient data or to telescoping
of ore zones. The mineralisation appears
to be epithermal gold-silver veins of low-
sulphidation type and a genetic relation-
ship with a porphyry-type molybdenum
deposit below Flammefjeld has been pro-
posed.
Skaergaard mafic intrusion-host-
ed, stratiform PGE-Au deposit
ed, stratiform PGE-Au deposit
The 54.5 Ma old Skaergaard intrusion is
extensively studied and has for decades
been a prime example of fractional crys-
extensively studied and has for decades
been a prime example of fractional crys-
tallisation of basaltic melt in a closed sys-
tem (68°N). Spectacular layering has made
the intrusion famous. The intrusion has
recently been suggested to be box-shaped
(c. 11 x 7 km and 4 km deep), with a total
volume of c. 400 km
tem (68°N). Spectacular layering has made
the intrusion famous. The intrusion has
recently been suggested to be box-shaped
(c. 11 x 7 km and 4 km deep), with a total
volume of c. 400 km
3
. A ferro-basalt
magma filled the magma chamber. The
Marginal Border Series crystallised along
the walls, the Upper Border Series under
the roof and the Layered Series accumu-
lated up from the floor leaving a residual
trace-element rich melt to crystallise in the
Sandwich Horizon c. 600 m below the
roof of the intrusion. The distinct layering
in the Layered Series is basin-shaped. The
c. 3,000 m of gabbros in the Layered Series
are on basis of liquidus parageneses divid-
Marginal Border Series crystallised along
the walls, the Upper Border Series under
the roof and the Layered Series accumu-
lated up from the floor leaving a residual
trace-element rich melt to crystallise in the
Sandwich Horizon c. 600 m below the
roof of the intrusion. The distinct layering
in the Layered Series is basin-shaped. The
c. 3,000 m of gabbros in the Layered Series
are on basis of liquidus parageneses divid-
ed in the unexposed Hidden Zone (olivine
and plagioclase), Lower Zone (olivine, pla-
gioclase, +/- clinopyroxene, ilmenite and
magnetite), Middle Zone (plagioclase, clino-
pyroxene, pigeonite, magnetite and ilmenite)
and Upper Zone (Fe-rich olivine, plagioclase,
clinopyroxene, magnetite, ilmenite, +/-
apatite and ferrobustamite). The cryptic
variation in the minerals is significant. Oli-
vine evolves from c. Fo
and plagioclase), Lower Zone (olivine, pla-
gioclase, +/- clinopyroxene, ilmenite and
magnetite), Middle Zone (plagioclase, clino-
pyroxene, pigeonite, magnetite and ilmenite)
and Upper Zone (Fe-rich olivine, plagioclase,
clinopyroxene, magnetite, ilmenite, +/-
apatite and ferrobustamite). The cryptic
variation in the minerals is significant. Oli-
vine evolves from c. Fo
70
tOFo
1
and plagio-
clase from An
70
to An
10
.
9
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Swarm of epithermal veins at the margin of
Flammefjeld breccia pipe (upper right). The per-
son clad in red in the centre of the picture is
collecting a chip sample, which returned 0.3
ppm Au, 127 ppm Ag, 1.4% Pb, 3.2% Zn and
0.8% Cu over 4 m.
Flammefjeld breccia pipe (upper right). The per-
son clad in red in the centre of the picture is
collecting a chip sample, which returned 0.3
ppm Au, 127 ppm Ag, 1.4% Pb, 3.2% Zn and
0.8% Cu over 4 m.
Cut surface of colloform structures in quartz-
carbonate gangue from Amdrup Fjord epither-
mal vein.
carbonate gangue from Amdrup Fjord epither-
mal vein.
The upper part of Middle Zone (Triple
Group) hosts a large tonnage low-grade
PGE and gold mineralisation. It is strati-
form, and ten levels enriched in PGE, all
perfectly concordant with the magmatic
layering, are identified in the centre of the
intrusion. The number of PGE levels de-
crease towards the margins of the intrusion,
where only one level is developed. The low-
est PGE level is the main reservoir of PGE.
It is up to 5 m thick at 1 ppm cut-off. All
other mineralised levels contain <1 ppm
PGE. Gold is always concentrated in the
PGE and gold mineralisation. It is strati-
form, and ten levels enriched in PGE, all
perfectly concordant with the magmatic
layering, are identified in the centre of the
intrusion. The number of PGE levels de-
crease towards the margins of the intrusion,
where only one level is developed. The low-
est PGE level is the main reservoir of PGE.
It is up to 5 m thick at 1 ppm cut-off. All
other mineralised levels contain <1 ppm
PGE. Gold is always concentrated in the
uppermost PGE level, irrespectively of the
number of developed levels. The gold-rich
zones are up to 2 m at 1 ppm cut-off.
number of developed levels. The gold-rich
zones are up to 2 m at 1 ppm cut-off.
The dominant precious metal phases are
alloys of palladium, gold and copper, vary-
ing from Skaergaardite (PdCu) to tetraauri-
cupride (AuCu), with locally significant
proportions of sulphides such as vysotskite
(PdS). The precious metal minerals are
hosted in, or occur near, primary magmat-
ic sulphides dominated by bornite and
chalcocite. Primary droplets of copper sul-
phide with precious metal grains are com-
ing from Skaergaardite (PdCu) to tetraauri-
cupride (AuCu), with locally significant
proportions of sulphides such as vysotskite
(PdS). The precious metal minerals are
hosted in, or occur near, primary magmat-
ic sulphides dominated by bornite and
chalcocite. Primary droplets of copper sul-
phide with precious metal grains are com-
mon. The structure of the mineralisation
and its petrography and mineralogy, sug-
gest that the mineralisation has formed at
high magmatic temperatures with little post-
solidification remobilisation.
and its petrography and mineralogy, sug-
gest that the mineralisation has formed at
high magmatic temperatures with little post-
solidification remobilisation.
To date, a total of 42 drill holes, corre-
sponding to 21,534 m, have been drilled
10
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
UZ
UBS
68°
10'
10'
31°40'
2 km
MZ
G
LZ
B
MZ
UZ
Forbindelsesg
letsc
he
r
MBS
MBS
1600 m
1000 m
sea level
Basalt
Marginal
Border
Series
Gneiss
North
South
Hidde
n Zo
ne
Lower Zone
Mid
dle Zone
Basistopp
en Sheet
Upp
er Zon
e
Marginal
Border
Series
1600 m
1000 m
sea level
Triple Group:
PGE-Au Horizons
Ice
Upper Border Series
Fault
Simplified geological map of the Skaergaard
intrusion.
intrusion.
Section through the Skaergaard intrusion.
The north-eastern part of the Skaergaard intrusion with Forbindelsesgletscher to the right. The Triple Group in 1200 m peak is arrowed.
from the surface by Platinova A/S and
Skaergaard Minerals Corp. Based on this,
Skaergaard Minerals announced an infer-
red mineral resource estimate in 2005. It
operates with a "Combined Zone" of vari-
able thickness, with a "Palladium Zone" at
the bottom and a "Gold Zone" at the top,
and shows a total tonnage of 1,520 Mt
grading 0.21 ppm Au, 0.61 ppm Pd and
0.04 ppm Pt. This includes 107 Mt in the
Gold Zone with 1.68 ppm Au, 0.59 ppm
Pd and 0.05 ppm Pt, and 104 Mt in the
Palladium Zone with 0.11 ppm Au, 1.91
ppm Pd and 0.16 ppm Pt. Titanium, iron
and vanadium are important commodities
in the Combined Zone, but the available
data are insufficient for the resource esti-
mate. However, average bulk concentra-
tions in a single profile across the central
part of the Combined Zone are 6.6% TiO
Skaergaard Minerals Corp. Based on this,
Skaergaard Minerals announced an infer-
red mineral resource estimate in 2005. It
operates with a "Combined Zone" of vari-
able thickness, with a "Palladium Zone" at
the bottom and a "Gold Zone" at the top,
and shows a total tonnage of 1,520 Mt
grading 0.21 ppm Au, 0.61 ppm Pd and
0.04 ppm Pt. This includes 107 Mt in the
Gold Zone with 1.68 ppm Au, 0.59 ppm
Pd and 0.05 ppm Pt, and 104 Mt in the
Palladium Zone with 0.11 ppm Au, 1.91
ppm Pd and 0.16 ppm Pt. Titanium, iron
and vanadium are important commodities
in the Combined Zone, but the available
data are insufficient for the resource esti-
mate. However, average bulk concentra-
tions in a single profile across the central
part of the Combined Zone are 6.6% TiO
2
,
19.4% Fe
2
O
3
and 840 ppm V over 44 m.
Kap Edvard Holm mafic intru-
sion-hosted, stratiform PGE
prospect
sion-hosted, stratiform PGE
prospect
The 50 Ma old Kap Edvard Holm complex
is a large replenished basaltic complex
analogous to gabbro intrusions of the
ocean floor (68°N). Only a smaller propor-
tion of the complex is exposed due to
extensive ice cover. The size is difficult to
evaluate, and estimates vary between 400
and 800 km
is a large replenished basaltic complex
analogous to gabbro intrusions of the
ocean floor (68°N). Only a smaller propor-
tion of the complex is exposed due to
extensive ice cover. The size is difficult to
evaluate, and estimates vary between 400
and 800 km
2
. The complex was originally
subdivided into the Lower, Middle and
Upper Layered Series. In a more recent
consensus, the Middle Layered Series is
believed to represent a separate intrusive
body, and the Upper Layered Series in the
southern part of the complex is believed
to be the lateral equivalents of the Lower
Layered Series in the northern part of the
complex. The complex is intruded by a
suite of later syenite and granite intrusions.
Upper Layered Series. In a more recent
consensus, the Middle Layered Series is
believed to represent a separate intrusive
body, and the Upper Layered Series in the
southern part of the complex is believed
to be the lateral equivalents of the Lower
Layered Series in the northern part of the
complex. The complex is intruded by a
suite of later syenite and granite intrusions.
A PGE and gold anomaly has been iden-
tified over a distance of c. 30 km. The
anomaly, which appears to be stratabound,
runs <1 ppm pge and au over a couple of
metres. Anomalous high concentrations (up
to 3 ppm PGE and 3 ppm Au) were identi-
fied in 1990 in one packsack drill core and
in chip samples from the contact of a later
syenite intrusion. Follow-up drilling the
following summer did not confirm the ele-
vated values in the anomalous core.
anomaly, which appears to be stratabound,
runs <1 ppm pge and au over a couple of
metres. Anomalous high concentrations (up
to 3 ppm PGE and 3 ppm Au) were identi-
fied in 1990 in one packsack drill core and
in chip samples from the contact of a later
syenite intrusion. Follow-up drilling the
following summer did not confirm the ele-
vated values in the anomalous core.
Miki Fjord macrodyke:
mafic intrusion-hosted, contact-
related PGE-Au-Cu-Ni showing
mafic intrusion-hosted, contact-
related PGE-Au-Cu-Ni showing
The Miki Fjord macrodyke is a NE-trending
tholeiitic, gabbro dyke which is up to 500 m
wide and can be followed for more than 50
km inland (68°N). Field relations and simi-
larities to the Skaergaard intrusion suggest
that the dyke is c. 55 Ma old and contem-
poraneous with the Skaergaard intrusion.
tholeiitic, gabbro dyke which is up to 500 m
wide and can be followed for more than 50
km inland (68°N). Field relations and simi-
larities to the Skaergaard intrusion suggest
that the dyke is c. 55 Ma old and contem-
poraneous with the Skaergaard intrusion.
Near Miki Fjord, parts of the roof zone are
preserved in the high country, and the gab-
bros below the roof are strongly layered and
very rich in large rafts of hornfelsed lava. The
lower parts of the dyke exposed at the
coast are unlayered. The upper gabbros
show spectacular layering due to anortho-
sitic melt layers formed during anatectic
melting of altered basalt inclusions.
preserved in the high country, and the gab-
bros below the roof are strongly layered and
very rich in large rafts of hornfelsed lava. The
lower parts of the dyke exposed at the
coast are unlayered. The upper gabbros
show spectacular layering due to anortho-
sitic melt layers formed during anatectic
melting of altered basalt inclusions.
Contacts to the Precambrian basement
are characterised by rheomorphic melting
11
GEOLOGY AND ORE 6 / 2006
E A S T GREENLAND P A L A E O G E N E I N T R U S I O N S
Thin section and back scatter images illustrating petrographic relationships in the Skaergaard miner-
alisation. ab: droplets of intergrown bornite (born) and chalcosite (chc) enclosed in ilmenite (ilm)
and magnetite (mt); cd: skaergaardite (PdCu) in sulphide droplets; ef: free intergrowths of noble
metal minerals (VYS, KTH, ZV).
alisation. ab: droplets of intergrown bornite (born) and chalcosite (chc) enclosed in ilmenite (ilm)
and magnetite (mt); cd: skaergaardite (PdCu) in sulphide droplets; ef: free intergrowths of noble
metal minerals (VYS, KTH, ZV).
and formation of pillow contact zones
where melts derived from the basement
mingled with dyke melts. The contacts
host showings of massive and disseminat-
ed sulphides with up to 0.1 ppm Pt, 2.2
ppm Pd, 0.3 ppm Au, 2.18% Cu and
0.06% Ni, and the existence of larger
bodies of massive sulphides in the deeper
parts of the dyke has been indicated by a
geophysical survey. The mineralisation is
probably caused by contamination of
basaltic melt.
where melts derived from the basement
mingled with dyke melts. The contacts
host showings of massive and disseminat-
ed sulphides with up to 0.1 ppm Pt, 2.2
ppm Pd, 0.3 ppm Au, 2.18% Cu and
0.06% Ni, and the existence of larger
bodies of massive sulphides in the deeper
parts of the dyke has been indicated by a
geophysical survey. The mineralisation is
probably caused by contamination of
basaltic melt.
Mineral potential
The mineral potential of the Palaeogene
intrusions of East Greenland lies mainly
with porphyry-type molybdenum deposits,
mafic intrusion-hosted platinum group
elements, gold, copper and nickel, and
epithermal gold-silver. In view of the limit-
ed exploration carried out in this extensive
region, the chances of discovering new
deposits are believed to be very promising.
intrusions of East Greenland lies mainly
with porphyry-type molybdenum deposits,
mafic intrusion-hosted platinum group
elements, gold, copper and nickel, and
epithermal gold-silver. In view of the limit-
ed exploration carried out in this extensive
region, the chances of discovering new
deposits are believed to be very promising.
Key references
Bearth, P. 1959: On the alkali massif of the Werner
Bjerge in East Greenland. Meddelelser om
Grønland
153
, 4, 62 pp.
Brooks, C.K. & Nielsen, T.F.D. 1982: The
Phanerozoic development of the Kangerdlugssuaq
area, East Greenland. Meddelelser om Grønland
Geoscience
9
, 30 pp.
Brooks, C.K., Tegner, C., Stein, H. & Thomassen,
B. 2004: Re-Os and
40
Ar/
39
Ar ages of porphyry
molybdenum deposits in the East Greenland vol-
canic-rifted margin. Economic Geology
99
,
12151222.
Geyti, A. & Thomassen, B. 1984: Molybdenum
and precious metal mineralization at Flammefjeld,
Southeast Greenland. Economic Geology
79
,
19211929.
Harpøth, O., Pedersen, J.L., Schønwandt, H.K.
& Thomassen, B. 1986: The mineral occurrences
of central East Greenland. Meddelelser om
Grønland Geoscience
17
, 138 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.
Geological Society Special Publication (London)
30
, 489515.
Nielsen, T.F.D. 2002: Palaeogene intrusions and
magmatic complexes in East Greenland, 66 to
75°N. 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 intru-
sion. In: Mungall, J.E. (ed.): Exploration for
Platinum-Group Element Deposits. MAC Short
Course
35
, 431455. Ottawa: Mineralogical
Association of Canada.
Thomassen, B. 2005: The Blyklippen lead-zinc
mine at Mesters Vig, East Greenland. Geology &
Ore
5
, 12 pp.
Thomassen, B. & Krebs, J.D. 2001: Palaeogene
gold- and silver-bearing epithermal veins at
Amdrup Fjord, southern East Greenland.
Danmarks og Grønlands Geologiske Undersøgelse
Rapport
2001/133
, 78 pp.
Authors
Bjørn Thomassen &
Troels F.D. Nielsen, GEUS
Editor
Karsten Secher, GEUS
Graphic Production
Carsten E. Thuesen, GEUS
Printed
February 2006
Printers
Schultz Grafisk
ISSN
1602-818x
Front cover photograph
South-west view over Amdrup
Fjord with epithermal vein in the
foreground. A grab sample
returned 1.4 ppm Au, 191 ppm
Ag, 1.4% Pb and 5.7% Zn.
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
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
GEOLOGY AND ORE 6 / 2006
Igneous layering in the Upper Zone of the Skaergaard intrusion.
12
Last modified: March 4, 2006
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