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Theme Magazines and Fact Sheets
EXPLORATION AND MINING IN GREENLANDGreenland Mineral Resources
Fact Sheet No. 7
Download pdf-file go_fs07.pdf (~1450 kbyte). Requires pdf-reader, Acrobat GSview or similar
The distribution of potentially diamondiferous
rocks in West Greenland shows a concentration
within the area from 60°N to 69°N. Outside this
area occurrences are scarce. In total nearly one
thousand localities with kimberlitic rocks in West
Greenland have been recorded, of which nearly
2/3 are found within a major alkaline province in
the region around 66°N. The density of occurren-
ces appears to partly reflect the uneven degree of
investigation of different areas, and partly the fact
that the rocks often occur in swarms. The commer-
cial exploration carried out in West Greenland
from 19922003 has mainly focused on the major
alkaline province. The investigations of the remai-
ning part of southern West Greenland has been of
more regional character.
rocks in West Greenland shows a concentration
within the area from 60°N to 69°N. Outside this
area occurrences are scarce. In total nearly one
thousand localities with kimberlitic rocks in West
Greenland have been recorded, of which nearly
2/3 are found within a major alkaline province in
the region around 66°N. The density of occurren-
ces appears to partly reflect the uneven degree of
investigation of different areas, and partly the fact
that the rocks often occur in swarms. The commer-
cial exploration carried out in West Greenland
from 19922003 has mainly focused on the major
alkaline province. The investigations of the remai-
ning part of southern West Greenland has been of
more regional character.
Exploration history
Greenland has seen several campaigns of diamond ex-
ploration since the early 1970s. Inspired by reports of
kimberlite dykes at several locations in southern West
ploration since the early 1970s. Inspired by reports of
kimberlite dykes at several locations in southern West
Greenland, Renzy Mines Ltd. investigated occurrences in
the Pyramidefjeld area north of Ivittuut in South-West
Greenland and recovered two microdiamonds and one
macrodiamond from kimberlitic samples. Early regional
kimberlite prospecting covering large parts of West
Greenland resulted in two microdiamonds extracted
from bulk stream sediment samples in the large
Arnangernup Kuua (`Sarfartoq') valley.
the Pyramidefjeld area north of Ivittuut in South-West
Greenland and recovered two microdiamonds and one
macrodiamond from kimberlitic samples. Early regional
kimberlite prospecting covering large parts of West
Greenland resulted in two microdiamonds extracted
from bulk stream sediment samples in the large
Arnangernup Kuua (`Sarfartoq') valley.
Industrial field campaigns from 1994 onwards have
been dedicated to regional till and stream sediment
sampling programmes with a view to locate kimberlite
indicator minerals. More than 13.000 sites have been
sampled and more than 100.000 suspected indicator
minerals analysed. Next followed airborne magnetic and
electromagnetic surveys and drilling for possible dia-
tremes on frozen lakes. The first diamonds from in situ
kimberlite was reported from the area east of Maniitsoq
in 1997 by Platinova A/S. One sample (792 kg) of a
large dyke yielded 25 microdiamonds ( <0.5 mm) and 16
macrodiamonds (all <1 mm).
been dedicated to regional till and stream sediment
sampling programmes with a view to locate kimberlite
indicator minerals. More than 13.000 sites have been
sampled and more than 100.000 suspected indicator
minerals analysed. Next followed airborne magnetic and
electromagnetic surveys and drilling for possible dia-
tremes on frozen lakes. The first diamonds from in situ
kimberlite was reported from the area east of Maniitsoq
in 1997 by Platinova A/S. One sample (792 kg) of a
large dyke yielded 25 microdiamonds ( <0.5 mm) and 16
macrodiamonds (all <1 mm).
The largest number of microdiamonds recovered
was from a field of large boulders of a suspected
dyke or sill that returned 474 microdiamonds and
5 macrodiamonds. Another striking discovery was
of a very large dyke that is traceable by geophysi-
cal means over a length of 5 km with a width of
20 m confirmed by two inclined drill holes. In
2002, GEUS and BMP conducted an airborne
hyperspectral survey over the Sarfartoq region in
order to assess this remote sensing technique for
detecting kimberlitic rocks and weathering materi-
al associated with them.
was from a field of large boulders of a suspected
dyke or sill that returned 474 microdiamonds and
5 macrodiamonds. Another striking discovery was
of a very large dyke that is traceable by geophysi-
cal means over a length of 5 km with a width of
20 m confirmed by two inclined drill holes. In
2002, GEUS and BMP conducted an airborne
hyperspectral survey over the Sarfartoq region in
order to assess this remote sensing technique for
detecting kimberlitic rocks and weathering materi-
al associated with them.
Survey fieldwork in 2001 and 2002 has been
focused on the spatial distribution of kimberlitic
dyke rocks in areas with limited previous informa-
tion, and detailed studies on mantle xenoliths
from the kimberlitic dykes. In 2003, GEUS and
BMP commenced a programme to test mini-bulk
samples of kimberlitic dykes for diamond content
by caustic fusion dissolution, and to determine
and characterise their indicator mineral popula-
tions and chemistries. Concurrently, research on
selecting further targets is conducted including a
new comprehensive age dating programme, pet-
focused on the spatial distribution of kimberlitic
dyke rocks in areas with limited previous informa-
tion, and detailed studies on mantle xenoliths
from the kimberlitic dykes. In 2003, GEUS and
BMP commenced a programme to test mini-bulk
samples of kimberlitic dykes for diamond content
by caustic fusion dissolution, and to determine
and characterise their indicator mineral popula-
tions and chemistries. Concurrently, research on
selecting further targets is conducted including a
new comprehensive age dating programme, pet-
Diamond exploration in
Greenland
Map showing the occurrences of kimberlitic rocks
(black dots) and diamond finds (yellow triangles).
(black dots) and diamond finds (yellow triangles).
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: S.M. Jensen & K. Secher
Editor: K.Secher
Layout: GEUS, Grafisk
© GEUS 2004
rography and studies on regional uplift and ther-
mal history of West Greenland.
mal history of West Greenland.
Geological environment
Southern West Greenland hosts a major alkaline
province with a variety of ultramafic alkaline rocks.
The alkaline province includes swarms of dykes
described as kimberlites and lamproites, and these
rock types are widely distributed in the Sisimiut
SarfartoqKangerlussuaq region, as well as the
region just south of Sukkertoppen Icecap. Lamp-
roitic dykes in the Sisimiut region are around 1.2
Ga old and the kimberlitic dykes in both the Sarfar-
toq and Sisimiut regions have ages of around 0.6
Ga. A precise spatial relationship between the in-
trusive events resulting in kimberlitic rocks and the
0.6 Ga Sarfartoq carbonatite complex has not been
established. The 170 Ma Qaqqaarsuk complex,
located in the area south of Sukkertoppen Icecap,
represents the youngest alkaline magmatic event.
province with a variety of ultramafic alkaline rocks.
The alkaline province includes swarms of dykes
described as kimberlites and lamproites, and these
rock types are widely distributed in the Sisimiut
SarfartoqKangerlussuaq region, as well as the
region just south of Sukkertoppen Icecap. Lamp-
roitic dykes in the Sisimiut region are around 1.2
Ga old and the kimberlitic dykes in both the Sarfar-
toq and Sisimiut regions have ages of around 0.6
Ga. A precise spatial relationship between the in-
trusive events resulting in kimberlitic rocks and the
0.6 Ga Sarfartoq carbonatite complex has not been
established. The 170 Ma Qaqqaarsuk complex,
located in the area south of Sukkertoppen Icecap,
represents the youngest alkaline magmatic event.
The kimberlitic intrusions are often flat-lying
sheets, rarely over 1 m wide, and traceable for a
few tens of metres, while others are subvertical,
12 m wide, and traceable for many hundreds of
metres. The dykes often contain numerous mantle
xenoliths ranging in size from a few millimetres to
sheets, rarely over 1 m wide, and traceable for a
few tens of metres, while others are subvertical,
12 m wide, and traceable for many hundreds of
metres. The dykes often contain numerous mantle
xenoliths ranging in size from a few millimetres to
several decime-
tres. Ubiquitous
kimberlitic or lam-
proitic boulders
ranging in size
from a few cen-
timetres to 2
metres across are
often concentrat-
ed in clusters or
trains that may
number hundreds
of boulders, and
be many hundreds
of metres long.
tres. Ubiquitous
kimberlitic or lam-
proitic boulders
ranging in size
from a few cen-
timetres to 2
metres across are
often concentrat-
ed in clusters or
trains that may
number hundreds
of boulders, and
be many hundreds
of metres long.
Concluding remarks
Most of the approximately 600 diamonds reported
to date are from just two areas, both located in the
unreworked Archaean craton. All in situ diamond
occurrences fall within areas outlined by the dia-
mond-favourable indicator minerals from till and
stream sediment samples. On a local scale, how-
ever, kimberlite tracing using indicator minerals
from till samples is not straightforward, probably
due to complex glacial dynamics. The most dia-
mond-favourable indicator minerals are distributed
far beyond the areas with known diamonds. This
observation, together with a regional structural
control, suggests that the potential appears to exist
on either side of the boundary between reworked
and unreworked Archaean basement.
to date are from just two areas, both located in the
unreworked Archaean craton. All in situ diamond
occurrences fall within areas outlined by the dia-
mond-favourable indicator minerals from till and
stream sediment samples. On a local scale, how-
ever, kimberlite tracing using indicator minerals
from till samples is not straightforward, probably
due to complex glacial dynamics. The most dia-
mond-favourable indicator minerals are distributed
far beyond the areas with known diamonds. This
observation, together with a regional structural
control, suggests that the potential appears to exist
on either side of the boundary between reworked
and unreworked Archaean basement.
Key references
Jensen, S.M., Hansen, H., Secher, K., Steenfelt, A., Schjøth, F.
& Rasmussen, T.M. 2002: Kimberlites and other ultramafic
alkaline rocks in the SisimiutKangerlussuaq region, south-
ern West Greenland. Geology of Greenland Survey Bulletin
191, 5766.
Jensen, S.M., Lind, M., Rasmussen, T.M., Schjøth, F. & Secher,
K. 2003: Diamond exploration data from West Greenland.
Danmarks og Grønlands Geologiske Undersøgelse Rapport
2003/21, 50 pp. + 1 DVD.
Jensen, S.M., Secher, K., Rasmussen, T.M., Tukiainen, T., Krebs,
J.D. & Schjøth, F. 2003: Distribution and magnetic signa-
tures of kimberlitic rocks in the Sarfartoq region, southern
West Greenland. 8th International Kimberlite Conference,
Victoria, B.C., Canada. Extended abstracts CD-ROM, 5 pp.
[Poster presentation in PDF format available from GEUS on
request].
Larsen, L.M. 1991: Occurrences of kimberlite, lamproite and
ultramafic lamprophyre in Greenland. Open File Series
Grønlands Geologiske Undersøgelse 91/2, 36 pp.
Larsen, L.M. & Rex, D.C.1992: A review of the 2500 Ma span
of alkaline-ultramafic, potassic and carbonatitic magmatism
in West Greenland. Lithos 28, 367402.
Exploration companies have produced a large vol-
ume of data relevant to diamond exploration since
1995. The data include mineral analyses of heavy
minerals recovered from till samples, dyke and
boulder distribution maps, geophysical surveys,
results of diamond testing of mini-bulk sampled
dykes, drill logs, etc. A recent digital compilation on
DVD provides a comprehensive overview of compa-
ny and Survey data available to the mining industry
(Jensen et al. 2003).
Kimberlite dyke (2m)
near Maniitsoq.
near Maniitsoq.
Last modified: February 17, 2004
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