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The PGE potential
in Greenland
No. 8 - February 2007
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Tasiilaq
Kangerlussuaq/
Skaergaard
Amitsoq
Sillisissanguit
Nunaat
Sillisissanguit
Nunaat
Qeqertarsuatsiaat
(Fiskenæsset)
Fiskefjord
Hammer Dal
Disko
The potential for Platinum Group Elem-
ent (PGE) resources in Greenland is
clear and encompasses mineralisation
in Precambrian to Palaeogene envi-
ronments. The PGE potential in Green-
land attracted interest already in the
1960s and has been part of the Survey's
considerations since the 1970s .
The corporate interest in PGE tar-
gets in Greenland was initiated by
Kryolitselskabet Øresund in the early
1960s and was related to a suite of
norites in West Greenland. Platinomino
A/S was established in 1968 to search
for Merensky Reef type deposits in
the Fiskenæsset Complex. In the late
1980s, Platinova Resources prospected
known PGE indications in Amitsoq peri-
dotites in southern Greenland. Since
1995 norites in the Tasiilaq region,
East Greenland have been the target
for Cu-Ni-PGE exploration by several
companies. In 2005 NunaMinerals ini-
tiated PGE exploration in the mafic
intrusions of the Fiskefjord area. In
the 1980s GEUS and university groups
focused on the formation of massive
sulphides in the Palaeogene basalts of
Disko Island, which has led to contin-
ued exploration for Noril´sk type min-
eralisations. Renewed academic stud-
ies and exploration by Platinova
Resources in the classic Skaergaard
intrusion (East Greenland) resulted in
1987 in the discovery of a reef-type,
world class PGE deposit.
Geological environment
for PGEs
Traces and showings of PGE mineralisation
are numerous in the Precambrian terrains
of Greenland. The Archaean of south-west
Greenland hosts anorthositic suites, like
the reworked Fiskenæsset complex (south
of Nuuk). The complex hosts accumulation
of chromite in anorthosite, and traces of
PGE mineralisation in Ni-sulphide segrega-
tions in amphibolite. The Archaean shield
north of Nuuk hosts the Maniitsoq Norite
Belt; a suite of leuconorite and gabbro rocks
in irregular bodies with traces of PGEs re-
lated to Ni-Cu-sulphide mineralisation.
Within the same region, large ultramafic
bodies and mafic layered complexes locally
show traces of PGE-mineralisation. The
Proteroizoic Ammassalik Belt on the East
coast of Greenland hosts a suite of norites
to which are related massive sulphide oc-
currences, potentially PGE-bearing.
Palaeogene Ni-sulphide occurrences with
potential PGE concentrations are known in
the West Greenland Basalt Province. Ex-
ploration has been carried out for more
than a century in the Disko Bay region.
Known occurrences are mainly hosted in
presumably contaminated lavas, and in
dykes at the base of the volcanic succes-
sion. Only reconnaissance investigations
have been performed in similar environ-
ments in East Greenland.
The main focus of PGE exploration in
the Palaeogene of East Greenland has been
the layered mafic intrusions in which many
mineralisations have been located, includ-
ing the Kap Edvard Holm complex and the
world class Platinova Reef within the Skaer-
gaard intrusion.
Archaean and Palaeo-
proterozoic settings
Fiskenæsset anorthosite complex:
Chromitite layered anorthosite intrusion.
The Archaean Fiskenæsset anorthosite com-
plex, with a strike length of> 200 km, is
hosted in high grade tonalitic gneiss. The
complex is named after the village Fiske-
næsset/Qeqertarsuatsiaat. The floor of the
intrusion has not been identified, but the
roof found immediately below flows of
mafic pillow lava. A detailed stratigraphy
shows a succession with a lower gabbro
unit followed by an ultramafic unit with
mineral-graded dunites, peridotites and
hornblendites. These are followed by a
lower leucograbbro unit with minor ultra-
mafic layers and a middle gabbro unit
with minor layers of anorthosite and ultra-
mafics and peridotites (hornblende-ortho-
pyroxene-spinel). Above these units follow
the upper leucogabbro unit with abundant
chromitite bands, an anorthosite unit and
the upper gabbro unit. The complex has
been repeatedly deformed and metamor-
2
GEOLOGY AND ORE 8 / 2007
The PGE potential in Greenland
Index map of localities on Greenland.
GO_08.qxp 23/02/07 13:16 Page 2
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phosed under amphibolite ­ and locally
granulite facies conditions.
Exploration
PGE exploration has been limited. In the
1970s Platinomino A/S searched for Meren-
sky type platinum deposits. The impetus
was the discovery of an approx. 1 metre
wide bronzitite layer with discrete chromite
banding. The bronzitite contains minor
nickel sulphides. Assays gave very promis-
ing results of up to 0.6 ppm Pt and 3 ppm
Pd which, however, could not be confirmed.
In 1980 study of one stratigraphical
section in the anorthosite complex showed
that PGEs are concentrated mainly in ultra-
mafic lithologies and chromitites. The lat-
ter contain up to 310 ppb Pt, 175 ppb Pd
and 220 ppb Rh. Similar concentrations
also occur in anorthosites and leucogab-
bros rich in disseminated sulphides.
In 1991 GEUS resampled the bronzitite
and a few other parts of the anorthosite
complex. The bronzitite gave 74 ppb Pt and
115 ppb Pd. In other parts of the anortho-
site complex, several-hundred-metre-thick
3
THE PGE POTENTIAL IN GREENLAND
Chromitite banded anorthosites from the Fiskenæsset anorthosites complex, southern West Greenland. Photo: GEUS.
Bronzitite layer in anorthosites from the Fiskenæsset anorthosites complex, southern West
Greenland. Photo: GEUS.
GO_08.qxp 23/02/07 13:16 Page 3
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lenses of ultrabasites with small amounts
of sulphide have been found. Some have
been chip and channel sampled. The best
results sOFar are 83 ppb Pt and 693 ppb
Pd, average over 2 metres. An ultramafic
sheet near the bronzitite unit yielded 68
ppb Pt and 361 ppb Pd over 1 metre.
Sillisissanguit Nunaat -
Maniitsoq Norite Belt:
Mafic intrusions and amphibolite layers.
The Norite Belt (15 x 75 km) is located east
of Maniitsoq and hosts a suite of irregular
bodies of basic rocks intruding into the
regional gneiss complex of the Akia terrane.
The bodies vary in size from 2 x 4 km down
to 10 x 20 m. They are predominantly com-
posed of gabbronorite and leucogabbro,
collectively referred to as norite. Primary
textures, such as igneous layering, are local-
ly preserved. Elevated Ni, Cu and PGE con-
centrations are found in sulphide showings
of apparently magmatic origin. The sul-
phides may show some degree of meta-
morphic remobilisation.
The norite rocks are very homogeneous
bodies with rare igneous banding composed
of alternating layers of plagioclase and hyp-
ersthene with accessory chromite. Amphi-
bolite layers are locally associated to the
norites.
Geotectonic setting
The Norite Belt is located along the east-
ern flank of the dome of the Finnefjeld
gneiss complex. The structure of the belt
seems controlled by the 3034 Ma old
Finnefjeld gneiss. The norites appear little
affected by the high grade retrograde
metamorphism observed in the surround-
ing basement. The Norite Belt can be
divided in a northern part characterised by
few large norite bodies and a southern
part of several, but smaller bodies and
pods of norite.
The age of the Norite Belt is uncertain,
but is probably around 3.0 Ga. Post-kine-
matic diorite intrusions in the Niaqunngu-
naq/Fiskefjord region (south of the Norite
Belt) are tentatively correlated to the Norite
Belt. The diorites are 2975 ± 13 Ma old.
Exploration
The norite bodies have been targets for
exploration since 1965, but only a few
PGE analyses are available from the early
exploration. Kryolitselskabet Øresund A/S
reported a typical Ni:Pd+Pt ratio in sul-
phide mineralisation of 50 000:1. New
analyses from 2001 gave:
4
Sukkertoppen
S. I
sor
toq
Ta
se
rs
suatsiaq
K
an
gi
a
15 km
65°
65°
52°
52°
Carbonatite
Gneis undifferentiated
Fault
Norite
Finnefjeld gneis
THE PGE POTENTIAL IN GREENLAND
Sketch map of the West Greenland Norite Belt.
Igneous layering in a norite body from the West Greenland Norite Belt,
Sillissisanguit nunat. Photo: GEUS.
Typical weathered surface of a norite boulder from the West Greenland
Norite Belt, Sillissisanguit nunat. Photo: GEUS.
GEOLOGY AND ORE 8 / 2007
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· Peak values for Pd of 0.6 ppm in three
sulphide-bearing samples of norite and
amphibolite, and of 0.2­0.4 ppm in
five sulphide-bearing samples of norite
and amphibolite.
· A peak value for Pt of 2.2 ppm in one
sample and of 0.7 ppm in four sam-
ples, all from heavily mineralised and
altered gabbro and amphibolite related
to the norites. Five samples of miner-
alised norite showed concentrations of
0.2­0.6 ppm.
· Four mineralised samples show a total
PGE (Pd+Pt) of 1.0­2.7 ppm
Mineralisation and associated
rock types
Elevated PGE numbers are found in
norites and amphibolites related to zones
enriched in sulphides. Rust zones and gos-
sans identify zones enriched in sulphides.
The sulphides occur as disseminations,
veinlets, interstitial fillings and as more
massive lenses. The showings are general-
ly a few tens of metres long. The sulphide
occurrences show an uneven distribution.
No economic deposit has been located,
despite the common occurrence of sul-
phide accumulations. The mineral assem-
blage is rather uniform, with pyrrhotite as
the predominant mineral accompanied by
chalcopyrite, pyrite and pentlandite in a
primary texture together with pyrite, lin-
neaite, bravoite and magnetite in replace-
5
THE PGE POTENTIAL IN GREENLAND
Slope with weathered dunite from the Fiskevandet region, southern West Greenland. Photo:
NunaMinerals A/S.
Rustzone enriched in PGE (
2.8 ppm) in an
amphibolitic sequence along the eastern flank
of the West Greenland Norite Belt. Photo:GEUS.
GO_08.qxp 23/02/07 13:16 Page 5
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6
GEOLOGY AND ORE 8 / 2007
Drilling in dunite by NunaMinerals A/S in the Fiskevandet region, southern West Greenland. Photo: NunaMinerals A/S.
THE PGE POTENTIAL IN GREENLAND
ment textures. The average sulphide con-
tent in the mineralised rocks is around 2
vol.% and locally up to 25 vol.%.
The Ni-Cu sulphide occurrences show a
rather uniform Pd /Pt, but the absolute
concentration is dependent on the sul-
phide content. High concentration - up to
2.7 ppm - is believed to be the result of
remobilisation.
Fiskefjord­Amikoq:
Ultramafic intrusions: irregular bodies of
dunite and peridotite.
Several layered mafic to ultramafic intru-
sions are embedded in a supracrustal belt
within the Archean gneiss terrain. Igneous
layering is common, despite strong defor-
mation.
Exploration and ore composition
NunaMinerals A/S acquired the Fiskefjord
licenses in 2005 and initiated PGE explo-
ration soon after. Stream sediment samples
demonstrate a wide range of PGE concen-
trations from weakly anomalous to a max-
imum content of> 600 ppb, combined Pt
and Pd. NunaMinerals named the two
prospect subareas Amikoq and Fiskevandet.
Exploration drilling is ongoing in the Amikoq
area.
Analysis of whole-rock samples has re-
turned values up to 4.5 ppm PGE (com-
Sampling site in scree with Pt-enriched weathered amphibolite bordering dunite, Fiskevandet region,
southern West Greenland. Photo: NunaMinerals A/S.
GO_08.qxp 23/02/07 13:16 Page 6
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bined) and samples show high Pt/Pd ratios.
Most samples have high contents of Cr
and Ni (up to 3.7 % and 2.8 %, respec-
tively) and moderately high Cu. The majority
of samples are depleted in S and sulphides
are rarely observed in hand specimens.
Whole-rock samples are Pt-dominated
with Pt/Pd ratios around 2.7. Cu/Pd displays
a wide range, indicating that the physical
conditions were favourable for substantial
PGE enrichment in the melt during mantle
melting. The parental magma(s) were rela-
tively PGE-rich and S-undersaturated and
could potentially have generated significant
PGE mineralisation. A high Pt/Pd ratio is
observed at three localities.
Tasiilaq:
Ammassalik Igneous complex.
The syntectonic norite complex is located
within the northern half of the Ammassalik
Mobile Belt, assumed to be the eastern
continuation of the Paleoproterozoic Nag-
ssugtoqidian orogen in West Greenland
and the Torngat orogen in Canada. The
belt consists of alternating re-worked
Archaean rocks, with tectonically inter-
leaved sheets of quartzo-feldspathic ortho-
gneisses and early Proterozoic supracrustal
rocks including komatiitic ultramafics.
The Ammassalik Igneous complex in the
Tasiilaq area is enveloped by supracrustal
gneisses and has been the object of explo-
ration since 1995. Exploration in the Am-
massalik Island and Kitak concessions has
been conducted since 1998 by NunaMin-
erals A/S and later by Inco Ltd and Diamond
Fields International. A joint venture opera-
tion between Diamond Fields International
and GEOARC/PF&U was initiated in 2003.
<--
Exploration
Early exploration led to the discovery of
Ni-Cu sulphides hosted in a komatiitic set-
ting. A lens of massive sulphide (440 m2)
was found in partly serpentinised ultramafic
rocks hosted in gossanous supracrustals on
the south coast of the Ammassalik Island.
Systematic surface sampling of the lense
showed an average of 0.98 % nickel,
0.33 % copper, 553 ppm cobalt and 510
ppb combined Au-PGE.
The Ammassalik occurrence displays
Proterozoic komatiite-related Ni-Cu deposits.
The komatiitic host rock has a high magne-
sium content ranging from 25 to 30 wt.%.
Diamond drilling at three localities in 2005
outlined a new sulphide occurrence with
up to 1.5% nickel.
Amitsoq:
Amitsoq-Nanortalik peridotite intrusions.
Four PGE-bearing ultramafic hornblende
peridotite intrusions have been recorded
on Nanortalik peninsula and the island of
Amitsoq in South Greenland. The intrusions
were investigated in 1987 by Platinova
Resources Ltd. and Boulder Gold N.L.
Exploration ceased after a few years due
to modest PGE contents. The ultramafic
plugs in the Nanortalik region may be re-
lated to an appinite suite observed through-
out the Ketilidian orogen across the south-
ern tip of Greenland.
7
THE PGE POTENTIAL IN GREENLAND
Hornblendite intrusion from the Amitsoq locality, South Greenland. Photo: GEUS.
GO_08.qxp 23/02/07 13:16 Page 7
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Two small plugs of layered ultramafics
occur on the south shore of Søndre Sermilik.
· A hornblende peridotite body is ex-
posed five km south of the Ippatit valley.
It hosts the "Waldorf" PGE showing.
The peridotite body is exposed> 200
metres along the shore and 350 metres
inland. Small exposures of peridotite
indicate that the body is> 2.5 km across.
The peridotite contains about 1 vol.%
disseminated sulphides. Grab samples
showed up to 280 ppb platinum and
330 ppb palladium, and drill-core sam-
ples yielded up to 100 ppb Pt and only
40 ppb Pd.
· A hornblendite-peridotite intrusion
occurs on central Amitsoq. It has been
observed over a length of 1.5 km, and
from the shore and inland to 335 m
a.s.l. It is an E-W striking dyke-like body
that pinches and swells in three dimen-
sions. Widths vary between 90 and
250 metres. The sulphide content is
about 0.2 vol. % , but reaches 15% in
10-20 cm wide zones. Pyrrhotite, pent-
landite, chalcopyrite, and cubanite domi-
nate the sulphides, accompanied by 5-
10 vol. % magnetite. Traces of gold,
platinum, and palladium were reported
from the showing in 1970.
Palaeogene settings
(West and East coast)
Disko Island:
Flood basalt related Palaeogene Ni-sulphide
occurrences with PGE (Noril´sk type).
For more than a century the Palaeogene
West Greenland Basalt province has seen
exploration for Ni-sulphides and PGE. The
known occurrences in the Disko Bugt region
are mainly hosted in contaminated lavas,
and in dykes at the base of the volcanic
succession. The province is believed to have
a significant potential for PGE-Ni-minerali-
sation.
Palaeogene picrite and basalt lavas over-
lie thick Upper Cretaceous and Palaeogene
sediments. Most of the voluminous on-
shore volcanics were deposited in a short
period of time 61­59 Ma ago. The Palaeo-
gene dyke intrusions, such as the Hammer
Dal complex on northwest Disko, contain
nickel-bearing pyrrhotite and native iron
formed by processes akin to Noril´sk type
Ni-Cu-PGE deposits. The analogy to Noril´sk
has attracted exploration, e.g. by Falcon-
bridge and Vismand. The Hammer Dal
complex on Disko belongs to a swarm of
mineralised dykes fed by contaminated
magma and the complex has a number of
attractive characteristics. It is the richest
metallic iron deposit in the region and it
relates spatially to the most intense hydro-
thermal alteration field on Disko. A field
that may imply the existence of a large in-
trusion at depth. Ground geophysics have
revealed a large conductor at 400­500 m
below the present surface. The conducter
could represent a volcanic body with sul-
phides and metallic iron.
Exploration and evaluation
of potential resources
The prospective area on north-west Disko
(Hammer Dal) is defined by a swarm of
NW-SE to N-S striking dykes and subvol-
canic intrusions of basaltic melt. The dykes
were probably feeders to large volumes of
contaminated lavas. The intrusions host
deposits of metallic iron and sulphides, all
of which at the moment are too small to
be economically viable. "Branched iron
THE PGE POTENTIAL IN GREENLAND
8
GEOLOGY AND ORE 8 / 2007
Rusty layer of iron basalt at the Asuk beach on the northern coast of Disko, central West Greenland.
Photo: A.K.Pedersen.
Basalt chunk with accumulation of metallic iron, Disko Island, central West Greenland.
Photo: A.K.Pedersen.
GO_08.qxp 23/02/07 13:16 Page 8
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THE PGE POTENTIAL IN GREENLAND
9
bodies" dominate the ore cumulates de-
posited along the steep (70º) contacts by
a mechanism that is not completely under-
stood.
The presence of iron cumulates suggests
considerable magma transport capability
in the magma. The amount of deposited
iron typically reflects local conditions of
deposition rather than the general poten-
tial of the intrusive system. Apart from
native (metallic) iron (and alloys), pyrrhotite
and pentlandite are common. Sulphide-
enriched basalt (together with accumulat-
ed, metallic iron) shows> 1% Ni and ele-
vated PGE contents, up to 0.5 ppm. A
final evaluation of the PGE potential in
this setting is not possible at present.
Exploration was carried out in the area
in the 1980s by Greenex/Cominco Ltd. A
Platinova A/S-Falconbridge Greenland A/S
joint venture conducted an extensive pro-
500 m high mountain slope of iron-rich basalt layers in the southern part
of Disko Island, central West Greenland. Photo: A.K.Pedersen.
GO_08.qxp 23/02/07 13:16 Page 9
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gramme between 1991 and 1996. The
programme included regional mapping and
sampling and diamond drilling.
Since 2003 Vismand Exploration Inc. has
searched for possible deposits on Disko
Island. The company collected three geo-
physical "Titan 24" cross-sections in the
northern part of Disko Island. The aim was
to locate nickel-enriched, deeper-lying, lava
conduits that connect to successions of con-
taminated flood basalts. A large conductor
at 400­500 m below the present surface
may be such a mineralised magma conduit.
East Greenland Palaeogene
intrusions:
Layered gabbro intrusions.
More than sixty intrusions are recorded in
the Palaeogene East Greenland volcanic
rifted margin. The plutonic suites range
from ultramafic tOFelsic, from depleted
basaltic to highly alkaline, and from upper
crustal intrusions to subvolcanic centres
and breccia pipes with related epithermal
vein systems. The East Greenland magma-
tism occurred from 61 to 13 Ma ago. The
province hosts the world-class Skaergaard
PGE and Au deposit.
The East Greenland volcanic rifted mar-
gin developed prior to, during and after the
onset of seafloor spreading in the North
Atlantic. The flood basalt succession is> 7km
thick. Major sill complexes occur in Meso-
zoic to Paleocene sediments below the lavas.
A large domal uplift at the "Kanger-
lussuaq Triple Junction" (68ºN) is associat-
ed with the surfacing of the proto-Iceland
plume (55­50 Ma). Early picritic lavas show
strong similarities to Hawaiian lavas, where-
as overlying flood basalts show increasing
Icelandic affinities. A transition from intra-
plate to spreading-ridge magmatism is
illustrated.
Coast-parallel dyke swarm systems are
mostly related to magmatic centres dotted
along the East Greenland coast. Deep ero-
sion has exposed a number of magmatic
centres at and south of 68ºN. They com-
prise early gabbros - some with PGE and
Au mineralisations, followed by intermedi-
ate tOFelsic intrusions.
Exploration and resources
Mafic intrusions at Kangerlussuaq (68ºN)
and down the east coast to Nualik (67ºN)
have seen focussed PGE exploration since
1987. Plationova A/S, Quadrant Resources
and later Galahad Gold Ltd and Skaergaard
Minerals Corp. have conducted the explo-
ration. In 1987 the Skaergaard intrusion
was recognised as a large low-grade PGE
and Au deposit. The concession is present-
ly held by Platina Resources Ltd. Several
other mafic intrusions show PGE minerali-
sation, but apart from Skaergaard, no sig-
nificant deposits have been identified.
The Skaergaard intrusion (68ºN) and the
Kap Edvard Holm complex (68ºN) are rep-
resentatives of stratiform PGE and Au miner-
al accumulation where the 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, titani-
um and vanadium) occurrence. The Kap
Edvard Holm complex contains large-ton-
nage, low-grade, stratiform PGE-Au horizon
developed in a replenish magma chamber.
The Kruuse Fjord intrusion (67ºN) and
Mikis Fjord Macrodyke (68ºN) are repre-
sentatives of contact-related and sulphide-
hosted PGE mineralisation. Sulphides rich
in platinum group elements are found at
THE PGE POTENTIAL IN GREENLAND
10
GEOLOGY AND ORE 8 / 2007
1600 m
1000 m
sea level
Basalt
Marginal
Border
Series
Gneiss
North
South
Hid
den Z
one
Lowe
r Zon
e
Mid
dle Zone
Bas
isto
ppen
Sh
eet
Uppe
r Z
one
Marginal
Border
Series
1600 m
1000 m
sea level
Triple Group:
PGE-Au Horizons
Ice
Upper Border Series
Fault
?
Map of a N­S section through the Skaergaard intrusion in southern East Greenland.
Channel sampling of mineralised layers in the Upper Zone, of the Skaergaard Intrusion, southern East
Greenland. Photo: GEUS.
GO_08.qxp 23/02/07 13:16 Page 10
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11
GEMSTONES OF GREENLAND
contacts between mafic intrusive units and
basement or other intrusive units.
The Skaergaard intrusion
The intrusion was emplaced during the
build up of the regional flood basalts and
the initial stages of continental rifting and
seafloor spreading in the North Atlantic.
The intrusion is currently modelled as a box-
like magma chamber c. 11 by 7.5 km in
surface area with an original stratigraphy
of c. 3.8 km.
The magma solidified in concentric
zones toward the centre of the intrusion.
Phase layering, i.e., liquidus parageneses,
and cryptic variation in liquidus minerals
allow a subdivision of the intrusion. The
cryptic variation in minerals is significant.
Olivine evolves from c. Fo70 tOFo1, and
plagioclase from c. An70 to An10.The
deepest gabbros in the Layered Series (LS)
are not exposed and are referred to as the
Hidden Zone (HZ). The exposed rocks of
LS are divided in Lower Zone (LZ), Middle
Zone (MZ), and Upper Zone (UZ).
The mineralisation is hosted in the
Triple Group in the upper part of the MZ
after the crystallisation of c. 70 % of the
parental ferrobasalt magma. The Triple
Group is the name of a c. 100 m thick
stratigraphy characterised by three, distinct,
leucogabbro layers. The mineralisation is
composed of five main levels and in total
ten well-defined levels of enrichment in
PGE (Pd-levels). The stratigraphic separa-
tion between main Pd-levels is c. 10 metres.
All Pd-levels are perfectly parallel to the
well-developed saucer-shaped magmatic
layering in the host gabbros.
The number of developed Pd-levels de-
creases systematically toward the margins
of the intrusion, where only one Pd-level
(Pd5) is developed. Au is always concen-
trated in or just above the top of the locally
developed Pd-levels irrespective of the
number of developed Pd-levels. The strati-
graphic separation between the base of
Pd5 level and the top of the Au-rich zones
increases from c. 5 metres at the margin
to c. 60 metres in the centre of the miner-
alistion.
The mineralisation has a low suphide
content ( <0.5 vol. % bornite and chalco-
site). The precious metal grains occur in
sulphide droplets in liquidus minerals or
groundmass or as free precious metal
droplets in the groundmass of the Ti-, V-
and Fe-rich host rock. The dominant PGE
mineral is skaergaardite (PdCu) in the cen-
tre of the intrusion, and zviagintsevite
(Pd
3
Pb) at the eastern margin. The Au min-
eralogy is more complex, but dominated
by tetra-auricupride (AuCu).
The Skaergaard deposit is a PGE-Au
dominated multi-element mineralisation.
The host rocks are rich in titanium, vanadi-
um and iron. A 44 m profile across the de-
posit indicates average contents of 6.6%
TiO
2
, 1.3 kg/t V205 and 19% Fe in the
host rock of the precious metal accumula-
tion. The lowest Pd-level (Pd5) is the main
source of PGE and estimated to contain
104 million tonnes with of 0.11 g/t Au,
1.91 g/t Pd and 0.16 g/t Pt. The combined
gold zone is estimated to contain 107 mil-
lion tonnes with 1.68 g/t Au, 0.59 g/t Pd
and 0.05 g/t Pt.
Concluding remarks
The magmatic provinces in Greenland's
geology cover all periods of crustal evolu-
tion. Today PGE exploration can benefit
from dedicated exploration efforts for pre-
cious elements and an increased search
for nickel, which has been carried out in
recent years within a variety of magmatic
provinces.
Greenland has promising PGE deposits
of world-class scale, as well as smaller
scale occurrences, some with a proven
PGE potential, and others not yet fully
explored.
Back scatter images of selected Skaergaard minerals. c­d: skaergaardite (PdCu) in a sulphide droplet;
e­f: free intergrowths of various noble metals minerals.
GO_08.qxp 23/02/07 13:16 Page 11
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GEOLOGY AND ORE 8 / 2007
GEOLOGY AND ORE 8 / 2007
GEOLOGY AND ORE 7 / 2007
Key references
Appel, P. W. U. 1993: Gold and platinum-group
element anomalies in the Fiskenæsset stratiform
anorthosite complex, West Greenland. Geological
Survey of Greenland. Open File Series. 93/6 , 24 pp.
Harpøth, O., Pedersen, J. L., Schønwandt, H.K.
& Thomassen, B. 1986: The mineral occurrences
of central East Greenland. Meddelelser om Grøn-
land, Geoscience 17 , 1­139.
Lightfoot, P. C. and C. J. Hawkesworth 1997:
Flood basalts and magmatic Ni, Cu, and PGE sul-
phide mineralization: Comparative geochemistry
of the Noril'sk (Siberian Traps) and West Greenland
sequences. In: Large igneous provinces: conti-
nental, oceanic, and planetary flood volcanism.
J. J. Mahoney and M. F. Coffin (eds). American
Geophysical Union, Geophysical Monograph
Series, 100 , 357­380.
Myers, J. S., 1985: Stratigraphy and structure of
the Fiskenæsset Complex, southern West Green-
land. Grønlands Geologiske Undersøgelse Bulletin
150 , 72pp.
Nielsen T.F.D. 2004: The shape and volume of
the Skaergaard intrusion: implications for mass
balances and bulk composition. Journal of
Petrology 45 , 507­530.
Nielsen, T.F.D. & Bernstein, S. 2004: Maturation
of areas in the Tertiary of East Greenland for PGE-
Ni-Cu exploration. Danmarks og Grønlands
Geologiske Undersøgelse Rapport 2004/6 , 59
pp. (CD-ROM included).
Nielsen, T.F.D., Andersen, J.C.Ø. & Brooks, C.K.
2005: The Platinova Reef of the Skaergaard
intrusion. Mineralogical Association of Canada
Short Course 35 , 431­455.
Page, N. J., Myers, J. S., Haffty, J., Simon, F. O.
& Aruscavage, H. R. 1980: Platinum, paladium
and rhodium in the Fiskenæsset Complex, South-
western Greenland. Economic Geology. 75 ,
907­915.
Schönwandt, H. K. 1971: Mineralised ultramafic
rocks in South Greenland. Rapport Grønlands
Geologiske Undersøgelse, 35 : 30­31.
Schönwandt, H. K. 1972: Geological and geo-
physical work on ultramafic rocks in the Nanortalik
area, South Greenland. Rapport Grønlands
Geologiske Undersøgelse, 45 , 35­36.
Secher, K.1982: Noritic rocks and associated nickel-
copper-sulphide occurrences in Sukkertoppen
district, central West Greenland, GGU Rapport
115 , 30­34.
Secher, K. 2001: The Pd + Pt dispersion in noritic
and undifferentiated mafic rocks of the Archaean
craton east of Maniitsoq, southern West Green-
land, Danmarks og Grønlands Geologiske Under-
søgelse Rapport 2001/123 , 22 pp.
Steenfelt, A. 2001: Geochemical atlas of
Greenland ­ West and South Greenland, Dan-
marks og Grønlands Geologiske Undersøgelse
Rapport 2001/46 , 40 pp. (CD-ROM included).
Stendal, H. (ed.) 2000: Exploration in Greenland:
discoveries of the 1990s. Transactions of the
Institution of Mining and Metallurgy, section B,
Applied Earth Science 109 , B1­B66.
Ulff-Møller, F.1991: Magmatic platinum-nickel
occurrences in the Tertiary West Greenland Basalt
Province: prospecting by Greenex A/S in 1985-
1988." Open File Series Grønlands Geologiske
Undersøgelse, 91/1 . 37pp.
Front cover photograph
Layered dunite from the region of
Fiskevandet, southern West Greenland.
Photo: NunaMinerals A/S.
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
Author
K. Secher, P. Appel and T.F.D. Nielsen
Editor
Karsten Secher, GEUS
Graphic Production
Carsten E. Thuesen, GEUS
Photographs
GEUS unless otherwise stated
Printed
February 2007 © GEUS
Printers
Schultz Grafisk
ISSN
1602-818x
Layered sequences in the Upper Zone of the Skaergaard Intrusion, southern East Greenland.
Photo: GEUS.
GO_08.qxp 23/02/07 13:16 Page 12


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