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Theme Magazines and Fact Sheets
Download "Geology and Ore no. 15, February 2009" go15.pdf (~4.4 mb)
Mineral Resource
Assessments in
Greenland
No. 15 - February 2009
GO_15.qxp:GO-02 copy.qxp 2/11/09 10:50 AM
Throughout the world, effective and
successful exploration is the result of
multidisciplinary approaches integrat-
ing the latest in exploration concepts
with new technologies. For this to be
possible, access to solid geological back -
ground information and large amounts
of geoscience data are re quired.
Through determined and planned
efforts, the Bureau of Mine rals and
Petroleum (BMP) and the Geological
Survey of Denmark and Greenland
(GEUS) have been intensively involved
in the geological in vestigation of
Green land, and during the last couple
of decades with in creasing emphasis
on regional mineral resource assess-
ments involving all disciplines of earth
sciences. Very large amounts of data
and information have been acquired,
compiled and interpreted in various
assessment projects.
successful exploration is the result of
multidisciplinary approaches integrat-
ing the latest in exploration concepts
with new technologies. For this to be
possible, access to solid geological back -
ground information and large amounts
of geoscience data are re quired.
Through determined and planned
efforts, the Bureau of Mine rals and
Petroleum (BMP) and the Geological
Survey of Denmark and Greenland
(GEUS) have been intensively involved
in the geological in vestigation of
Green land, and during the last couple
of decades with in creasing emphasis
on regional mineral resource assess-
ments involving all disciplines of earth
sciences. Very large amounts of data
and information have been acquired,
compiled and interpreted in various
assessment projects.
The search for mineral resources
in Greenland
in Greenland
The motivation and for geological investi-
gations in Greenland have since the early
18
gations in Greenland have since the early
18
th
century been the search for
exploitable minerals. The first successful
mine was opened in the mid-19
mine was opened in the mid-19
th
century
and exploration continued, with some
quiet periods. Government-financed, sys-
tematic geological investigations aimed
towards `the next discovery' have always
provided part of the drive; with the Self-
Governance in Greenland just round the
corner, the mineral re sources in Greenland
are still very much on the political agenda.
Today, BMP and GEUS co-operate in the
effort to open Greenland to the interna-
tional ex ploration and mining industry. A
governing principle for the co-operation
has been to acquire, organise and make
available the many types of geoscience data
and at the same time publish maps and
papers describing the geological evolution
of Greenland and the potential for mineral
resources. In a series of projects over the
last two decades, the facilities, methods,
presentations and subjects have been
quiet periods. Government-financed, sys-
tematic geological investigations aimed
towards `the next discovery' have always
provided part of the drive; with the Self-
Governance in Greenland just round the
corner, the mineral re sources in Greenland
are still very much on the political agenda.
Today, BMP and GEUS co-operate in the
effort to open Greenland to the interna-
tional ex ploration and mining industry. A
governing principle for the co-operation
has been to acquire, organise and make
available the many types of geoscience data
and at the same time publish maps and
papers describing the geological evolution
of Greenland and the potential for mineral
resources. In a series of projects over the
last two decades, the facilities, methods,
presentations and subjects have been
developed and refined, greatly helped by
the development in computer sciences.
This magazine briefly describes the devel-
opment from thematic maps on paper to
maps and data in true GIS environment
taken for granted by today's explorationists.
the development in computer sciences.
This magazine briefly describes the devel-
opment from thematic maps on paper to
maps and data in true GIS environment
taken for granted by today's explorationists.
At the same time, understanding of the
potential for mineral resources in Green -
land has been advanced significantly, not
least through the efforts of the many ex -
ploration companies. However, it remains
true that major parts of Greenland have
land has been advanced significantly, not
least through the efforts of the many ex -
ploration companies. However, it remains
true that major parts of Greenland have
2
GEOLOGY AND ORE 15 / 2009
Mineral Resource Assessments
in Greenland
in Greenland
More than 100 years of mining.
Upper:
Sailing ships (1898) waiting to be loaded at the Ivittuut
Cryolite Mine in South Greenland. The open pit mine was active from 1854 to 1987. Lower: Bulk-
carrier (2006) alongside the deep-water pier at the Minelco Olivine Mine at the Seqi olivine deposit
in southern West Greenland. The deposit is located in a dunite body with 9599% olivine with a
high fostertitic content. The olivine is shipped to European and North American markets and used as
a first-rate additive in various metallurgical applications.
Cryolite Mine in South Greenland. The open pit mine was active from 1854 to 1987. Lower: Bulk-
carrier (2006) alongside the deep-water pier at the Minelco Olivine Mine at the Seqi olivine deposit
in southern West Greenland. The deposit is located in a dunite body with 9599% olivine with a
high fostertitic content. The olivine is shipped to European and North American markets and used as
a first-rate additive in various metallurgical applications.
been only superficially explored and may
be regarded as true juve nile `greenfields',
calling for much more in vestigation. The
activities of BMP and GEUS will continue
into to the benefit of the mining industry in
Greenland.
be regarded as true juve nile `greenfields',
calling for much more in vestigation. The
activities of BMP and GEUS will continue
into to the benefit of the mining industry in
Greenland.
From thematic maps to
regional GIS models
regional GIS models
During the first half of the 1990s a series
of thematic maps were published. This was
initiated by GEUS (the then Geological
Survey of Greenland, GGU) to make the
large collections of data more readily
available. It was the first attempt to pub-
lish comprehensive sets of regional data
on selected areas in Greenland in a stan-
dard scale and format. Most of the infor-
mation had not previously been compiled
or published. By using the new computer
methods, many maps (5060) could be
compiled showing all the different types of
geo-data for the same region. The objec-
tive was tOFacilitate the identification of
trends and boundaries important for the
recognition of favourable environments
for ore genesis. The maps were published
in paper format. The thematic map series
was discontinued in 1996, but by then the
GIS methods and programs had been suf-
of thematic maps were published. This was
initiated by GEUS (the then Geological
Survey of Greenland, GGU) to make the
large collections of data more readily
available. It was the first attempt to pub-
lish comprehensive sets of regional data
on selected areas in Greenland in a stan-
dard scale and format. Most of the infor-
mation had not previously been compiled
or published. By using the new computer
methods, many maps (5060) could be
compiled showing all the different types of
geo-data for the same region. The objec-
tive was tOFacilitate the identification of
trends and boundaries important for the
recognition of favourable environments
for ore genesis. The maps were published
in paper format. The thematic map series
was discontinued in 1996, but by then the
GIS methods and programs had been suf-
ficiently developed and widespread to make
it possible to replace the thematic paper
maps with digital maps in a GIS environ-
ment. The first such regional GIS compila-
tion or GIS model for mineral resource
purposes was published in 1998, by trans-
ferring the last thematic map series of
Inglefield Land into a new digital version
in the GIS environment. Since then, similar
compilations have been produced for four
other regions from the Disko Bugt in cen-
tral West Greenland to Kap Farvel, South
Greenland. Within the next few years, also
South-East Greenland will be covered as
part of the upcoming mineral resource
assessment programme of that region.
it possible to replace the thematic paper
maps with digital maps in a GIS environ-
ment. The first such regional GIS compila-
tion or GIS model for mineral resource
purposes was published in 1998, by trans-
ferring the last thematic map series of
Inglefield Land into a new digital version
in the GIS environment. Since then, similar
compilations have been produced for four
other regions from the Disko Bugt in cen-
tral West Greenland to Kap Farvel, South
Greenland. Within the next few years, also
South-East Greenland will be covered as
part of the upcoming mineral resource
assessment programme of that region.
It all starts with data
BMP and GEUS wish to make data easily
available for distribution, but before that
can happen, enormous amounts of data
have to be quality controlled, positioned
on newer maps, assessed, displayed and
analysed. It was the initial step in the
compiling of thematic maps, and still is
when constructing GIS-models today, to
ensure that all data become available for
future users. New data acquired in many
public surveys, sampling and mapping
campaigns and research programmes are
available for distribution, but before that
can happen, enormous amounts of data
have to be quality controlled, positioned
on newer maps, assessed, displayed and
analysed. It was the initial step in the
compiling of thematic maps, and still is
when constructing GIS-models today, to
ensure that all data become available for
future users. New data acquired in many
public surveys, sampling and mapping
campaigns and research programmes are
also made immediately available to the
exploration industry.
exploration industry.
Geological mapping data
The year 2005 was a milestone in geologi-
cal mapping; full coverage of Greenland in
scale 1:500 000 was achieved. Published
maps in other scales cover more than half
of the ice-free parts of Greenland, provid-
ing basic and essential data, increasingly
in the form of digital maps. In addition,
the detailed field-maps made by the map-
ping geologist during the various cam-
paigns are stored at GEUS in digital for-
mat. The mapping of new areas and the
digital updating of existing maps are
ongoing processes and provide valuable
material for the GIS models produced for
the mineral resource assessment pro-
grammes.
The year 2005 was a milestone in geologi-
cal mapping; full coverage of Greenland in
scale 1:500 000 was achieved. Published
maps in other scales cover more than half
of the ice-free parts of Greenland, provid-
ing basic and essential data, increasingly
in the form of digital maps. In addition,
the detailed field-maps made by the map-
ping geologist during the various cam-
paigns are stored at GEUS in digital for-
mat. The mapping of new areas and the
digital updating of existing maps are
ongoing processes and provide valuable
material for the GIS models produced for
the mineral resource assessment pro-
grammes.
Geochemical data
In Greenland, regional stream sediment
geochemical mapping with an approximate
sample density of one sample per 30 km
In Greenland, regional stream sediment
geochemical mapping with an approximate
sample density of one sample per 30 km
2
was initiated in the early 1970s. In 2001, a
digital release of the `Geochemical Atlas of
Greenland West and South Greenland'
was presented. GEUS' databases contain
still more stream sediment geochemistry
data from the other parts of Greenland
digital release of the `Geochemical Atlas of
Greenland West and South Greenland'
was presented. GEUS' databases contain
still more stream sediment geochemistry
data from the other parts of Greenland
3
MINERAL RESOURCE ASSESSMENTS
500 km
1996
1990
1994
1994
Coverage of the thematic map series.
especially data from North, North-East and
northern East Greenland have been sys-
tematically acquired, and further geo-
chemical surveys are planned, as South-
East Greenland in 2009 and 2010. Other
compiled geochemistry datasets have been
released, e.g. the `Diamond exploration
data from West Green land' on DVD. This
compilation presents more than 96 000
mineral analyses from more than 15 200
samples of till or stream sediment samples
from West Green land, public data as well
as company data extracted from released,
non-confidential company reports of field
work campaigns. GEUS' lithogeochemical
database for Green land contains geochem-
istry of all analysed rock samples collected
during various Survey campaigns in Green -
land. All these data are included in the min-
eral resource asses sment programmes and
are available to the public.
northern East Greenland have been sys-
tematically acquired, and further geo-
chemical surveys are planned, as South-
East Greenland in 2009 and 2010. Other
compiled geochemistry datasets have been
released, e.g. the `Diamond exploration
data from West Green land' on DVD. This
compilation presents more than 96 000
mineral analyses from more than 15 200
samples of till or stream sediment samples
from West Green land, public data as well
as company data extracted from released,
non-confidential company reports of field
work campaigns. GEUS' lithogeochemical
database for Green land contains geochem-
istry of all analysed rock samples collected
during various Survey campaigns in Green -
land. All these data are included in the min-
eral resource asses sment programmes and
are available to the public.
Geophysical data
Airborne geophysical surveys of onshore
areas were utilised by companies in the
1960s and GGU in the 1970s. The onset
of the nineties marked the beginning of
more than a decade of systematic modern
regional geophysical data surveys in vari-
ous parts of Greenland financed by BMP
and GEUS. The AEM Greenland 19941998
Airborne geophysical surveys of onshore
areas were utilised by companies in the
1960s and GGU in the 1970s. The onset
of the nineties marked the beginning of
more than a decade of systematic modern
regional geophysical data surveys in vari-
ous parts of Greenland financed by BMP
and GEUS. The AEM Greenland 19941998
project produced high resolution detailed
multi-parameter surveys (electromagnetic,
magnetic and partly radiometric) in each
of the years from 1994 to 1998 producing
a total of 75 000 line kilometres. The
AEROMAG projects encompassed high-
multi-parameter surveys (electromagnetic,
magnetic and partly radiometric) in each
of the years from 1994 to 1998 producing
a total of 75 000 line kilometres. The
AEROMAG projects encompassed high-
resolution magnetic surveys conducted in
1992, each of the years from 1995 to
1999 and in 2001 producing a total of
515 000 line kilometres. The geophysical
datasets can be purchased from GEUS,
and are extensively used in the mineral
1992, each of the years from 1995 to
1999 and in 2001 producing a total of
515 000 line kilometres. The geophysical
datasets can be purchased from GEUS,
and are extensively used in the mineral
4
MINERAL RESOURCE ASSESSMENTS
GEOLOGY AND ORE 15 / 2009
500 km
1:100 000
1:250 000
500 km
Geologists collecting sediment samples for geochemical analysis.
Coverage of 1:250 000 and 1:100 000 scale geological maps.
Coverage of regional geochemistry data from stream sediment.
resource assessment programmes.
Additional onshore airborne surveys are
being considered for the near future.
Additional onshore airborne surveys are
being considered for the near future.
Remote sensing data
The 1990s also marked the serious onset
of remote sensing investigations in Green -
land, which have been ongoing since then
and in the later years have continued with
the gathering and analysis of hyper-spec-
tral data from several parts of Greenland.
The often excellent rock exposure in Green -
land makes processing of remote sensing
data a very interesting tool for the search
for mineralising systems and a very effec-
tive method, when addressing large juvenile
regions.
The 1990s also marked the serious onset
of remote sensing investigations in Green -
land, which have been ongoing since then
and in the later years have continued with
the gathering and analysis of hyper-spec-
tral data from several parts of Greenland.
The often excellent rock exposure in Green -
land makes processing of remote sensing
data a very interesting tool for the search
for mineralising systems and a very effec-
tive method, when addressing large juvenile
regions.
Mineral occurrence data
GEUS continuously compiles information
about mineralised sites in a mineral occur-
rence database. Mineral occurrence de -
scriptions are based on Survey field work
and subsequent analyses of data and on
review of existing Survey data as well as
released non-confidential company reports
and data. Furthermore, other geo-data on
the occurrence, such as geophysical, geo-
chemical and structural data are exam-
ined. If possible, the mineral oc currence is
placed in a geotectonic context and a
genetic model is suggested. The on-line
GIS facility GMOM (Greenland Mineral
Occurrence Map www.geus.dk/gmom) is
updated from the database, providing
direct public access to information about a
large number of localities, relevant from a
mineral resource assessment point of view.
GEUS continuously compiles information
about mineralised sites in a mineral occur-
rence database. Mineral occurrence de -
scriptions are based on Survey field work
and subsequent analyses of data and on
review of existing Survey data as well as
released non-confidential company reports
and data. Furthermore, other geo-data on
the occurrence, such as geophysical, geo-
chemical and structural data are exam-
ined. If possible, the mineral oc currence is
placed in a geotectonic context and a
genetic model is suggested. The on-line
GIS facility GMOM (Greenland Mineral
Occurrence Map www.geus.dk/gmom) is
updated from the database, providing
direct public access to information about a
large number of localities, relevant from a
mineral resource assessment point of view.
Company mining and exploration data
All companies doing exploration and min-
ing in Greenland must hand in reports to
BMP. These reports are on file at GEUS and
once released, they are always made acces -
sible to the public. Currently, the reports are
being scanned and arranged in an on-line
database DODEX (www.geus.dk/dodex).
Several mining and exploration compa-
nies, formerly active in Greenland, have
donated their entire data collections to
GEUS. These data are, however, not avail-
able on-line and therefore enquiries by
telephone or e-mail to GEUS are neces-
All companies doing exploration and min-
ing in Greenland must hand in reports to
BMP. These reports are on file at GEUS and
once released, they are always made acces -
sible to the public. Currently, the reports are
being scanned and arranged in an on-line
database DODEX (www.geus.dk/dodex).
Several mining and exploration compa-
nies, formerly active in Greenland, have
donated their entire data collections to
GEUS. These data are, however, not avail-
able on-line and therefore enquiries by
telephone or e-mail to GEUS are neces-
sary. The above sources provide a unique
collection of data for the assessments of
mineral sites, prospects, former mines and
regions.
collection of data for the assessments of
mineral sites, prospects, former mines and
regions.
Modern assessments using
digital data
digital data
More and more data become available in
digital format and technologies/software
have developed considerably. The regional
mineral resources assessment programmes
in Greenland have, since 1996, been car-
ried out based on multidisciplinary digital
data compilations, which have been made
generally accessible in a GIS environment,
published on CD-ROMs or DVDs. The digi-
tal data are supported by detailed descrip-
tions of mineralised sites, and all this makes
it possible for exploration companies to
access the geology of Greenland following
their own exploration strategies. GEUS
also uses the data to develop advanced,
general geological models viewed and
interpreted in the framework of geotec-
tonic and mineral deposit models. All min-
eral resource assessments have been
accompanied by intensive field work pro-
grammes, in which results from analyses
and interpretations of the region in focus
have been followed up and further eluci-
digital format and technologies/software
have developed considerably. The regional
mineral resources assessment programmes
in Greenland have, since 1996, been car-
ried out based on multidisciplinary digital
data compilations, which have been made
generally accessible in a GIS environment,
published on CD-ROMs or DVDs. The digi-
tal data are supported by detailed descrip-
tions of mineralised sites, and all this makes
it possible for exploration companies to
access the geology of Greenland following
their own exploration strategies. GEUS
also uses the data to develop advanced,
general geological models viewed and
interpreted in the framework of geotec-
tonic and mineral deposit models. All min-
eral resource assessments have been
accompanied by intensive field work pro-
grammes, in which results from analyses
and interpretations of the region in focus
have been followed up and further eluci-
dated. This includes gathering of new
datasets and new mapping. The field
work has often been conducted in co-
operation with exploration companies
active in the regions. Thus, very useful and
large data sets have become readily avail-
able for newcomers to Greenland. Some
of the digital datasets usually included in
the GIS models are:
datasets and new mapping. The field
work has often been conducted in co-
operation with exploration companies
active in the regions. Thus, very useful and
large data sets have become readily avail-
able for newcomers to Greenland. Some
of the digital datasets usually included in
the GIS models are:
· Topographic base map and digital ele-
vation model
· Geological map (scanned and digital
vectorised maps, published maps and
unpublished field maps)
unpublished field maps)
· Remote sensing data e.g. Mosaic of
Landsat TM and Aster scenes, hyper-
spectral data
spectral data
· Airborne magnetic, electromagnetic
and radiometric maps
· Gravity maps
· Sample locations and descriptions
· Lithogeochemistry
· Stream sediments and heavy mineral
· Sample locations and descriptions
· Lithogeochemistry
· Stream sediments and heavy mineral
concentrate geochemistry maps
· Mineral occurrence sites with descrip-
tions
· Mineral potential maps from integra-
tive data analyses
· Key-photos of rock types and mineral
occurrences
5
MINERAL RESOURCE ASSESSMENTS
500 km
Aeromag 1997
Aeromag 1997
Aeromag 2001
Aeromag 2001
Aeromag 1997
Aeromag 2001
Aeromag 1996
Aeromag 1998
AEM Greenland 1996
AEM Greenland 1996
AEM Greenland 1995
AEM Greenland 1995
AEM Greenland 1996
Aeromag 1995
AEM Greenland 1997
AEM Greenland 1994
AEM Greenland 1998 (1)
AEM Greenland 1998 (2)
Aeromag 1992
AEM Greenland 1995
Aeromag 1999
Coverage of modern regional, airborne onshore magnetic data.
· Overview of exploration licences
through time
· List of existing maps
· Bibliography, including company reports
· Bibliography, including company reports
New methods for mineral
resource assessment
resource assessment
In the modern quest for the acquisition
and analyses of geo-data, the traditional
approach to the assessment is further
strengthened by the application of several
new methods. This ensures that the full
benefits of the geoscience data become
apparent; the users are provided with an
insight that is not directly discernable in
the single data type but only becomes visi-
ble by integration of many types of data.
Some of the new approaches employed
are described here.
and analyses of geo-data, the traditional
approach to the assessment is further
strengthened by the application of several
new methods. This ensures that the full
benefits of the geoscience data become
apparent; the users are provided with an
insight that is not directly discernable in
the single data type but only becomes visi-
ble by integration of many types of data.
Some of the new approaches employed
are described here.
Holistic approach to the assessment
of mineral resources
Today, GEUS and BMP are making inte-
grated assessments including all acquired
data, information, and analyses are made
using a number of methods. Processing of
hyper-spectral data, 3-D modelling and
lithogeochemistry go hand-in-hand with
traditional mapping, modern geochronol-
ogy, etc. In the holistic approach all results
are being considered jointly and integrat-
ed to build geological models. The overall
objective of the assessment is still to
understand the crustal composition and
evolution, and to recognise environments
favourable for ore genesis, but the num-
ber of methods that are utilised and the
depth of the analyses have changed. This
holistic approach is the firm basis for GEUS'
ability to improve the geological knowledge
of Greenland through continued field work,
acquisition of data, applied scientific work
and resource evaluations.
of mineral resources
Today, GEUS and BMP are making inte-
grated assessments including all acquired
data, information, and analyses are made
using a number of methods. Processing of
hyper-spectral data, 3-D modelling and
lithogeochemistry go hand-in-hand with
traditional mapping, modern geochronol-
ogy, etc. In the holistic approach all results
are being considered jointly and integrat-
ed to build geological models. The overall
objective of the assessment is still to
understand the crustal composition and
evolution, and to recognise environments
favourable for ore genesis, but the num-
ber of methods that are utilised and the
depth of the analyses have changed. This
holistic approach is the firm basis for GEUS'
ability to improve the geological knowledge
of Greenland through continued field work,
acquisition of data, applied scientific work
and resource evaluations.
Quantitative integrated data analysis
As a part of the holistic approach to min-
eral resource assessment, quantitative
analyses of multivariable data are becom-
ing a central theme in the work with geo-
science data. Not only do such methods
allow the identification of quantitative
relations, which previously in most cases
As a part of the holistic approach to min-
eral resource assessment, quantitative
analyses of multivariable data are becom-
ing a central theme in the work with geo-
science data. Not only do such methods
allow the identification of quantitative
relations, which previously in most cases
6
GEOLOGY AND ORE 15 / 2009
MINERAL RESOURCE ASSESSMENTS
Coverage of modern regional, mineral resource assessments in GIS models.
500 km
20092014
20092014
20092014
2000
2000
2000
2010
2010
2010
2009
2009
2009
2004
2004
2004
1999
1999
1999
1998
1998
1998
Region
North-West Greenland
Central East Greenland
South Greenland
Central West Greenland
Nuuk region, southern
West Greenland
West Greenland
Southern West
Greenland
Greenland
South-East Greenland
Modern regional mineral resource assessments carried out or planned
Year
1998
1999
2000
2004
2008
2009
2009
2010
(ongoing)
(ongoing)
Ongoing
(2009;
2014)
(2009;
2014)
Geological province
Palaeoproterozoic
Inglefield Land mobile
belt
Inglefield Land mobile
belt
Neoproterozoic to
Permian rocks
Permian rocks
Palaeoproterozoic
Ketilidian mobile belt
Ketilidian mobile belt
Palaeoproterozoic
Nagssugtoqidian
orogen and Archaean
Disko Bugt
Nagssugtoqidian
orogen and Archaean
Disko Bugt
Archaean terranes
of the North Atlantic
craton
of the North Atlantic
craton
Archaean terranes
of the North Atlantic
craton
of the North Atlantic
craton
Archaean terranes of
the North Atlantic
craton and
Palaeoproterozoic
Ammassalik mobile belt
the North Atlantic
craton and
Palaeoproterozoic
Ammassalik mobile belt
Potential commodities
Gold, silver, copper, zinc and iron
Gold, silver, copper, lead,
tungsten, uranium
tungsten, uranium
Well-known metallogenetic province
for gold and uranium as well as potential
for platinum group elements, copper,
titanium, vanadium, zirconium,
rare earth elements, niobium, tantalum,
graphite
for gold and uranium as well as potential
for platinum group elements, copper,
titanium, vanadium, zirconium,
rare earth elements, niobium, tantalum,
graphite
Gold, copper, iron, nickel, graphite,
niobium, uranium, phosphate,
gemstone, diamond
niobium, uranium, phosphate,
gemstone, diamond
Gold, platinum-group elements, nickel,
tungsten, iron, industrial minerals (olivine),
gemstone
tungsten, iron, industrial minerals (olivine),
gemstone
Gold, chromium, vanadium, titanium,
platinum-group elements, ruby, gemstone
platinum-group elements, ruby, gemstone
Very poorly known part, with a potential
for gold, copper, platinum-group elements,
nickel, gemstones, diamonds
for gold, copper, platinum-group elements,
nickel, gemstones, diamonds
could only be expressed visually; they also
allow the extraction of trends or signa-
tures that formerly could not be recog-
nised. In the integrative data analysis, rela-
tionships between large and diverse data-
sets, which otherwise can be incompre-
hensible, are being analysed systematically.
The analyses are carried out using proba-
bilistic, statistical and data-mining models
and are always used in combination with
other approaches; the results are validated
statistically and geologically. This allows a
quantification of geological features, which
can be utilised in the formation of geolog-
ical models. In addition, the integrative
analysis allows predictions of e.g. certain
mineralising systems. The predictions are
made from the relationships of data signa-
tures for sites with known mineralising
systems, which are used in the search for
similar signatures in unexplored areas.
Alternatively they come from a search for
specific data signatures and relationships,
which by comparison with established
mineral deposit models are found to be
characteristic of the mineralising system.
allow the extraction of trends or signa-
tures that formerly could not be recog-
nised. In the integrative data analysis, rela-
tionships between large and diverse data-
sets, which otherwise can be incompre-
hensible, are being analysed systematically.
The analyses are carried out using proba-
bilistic, statistical and data-mining models
and are always used in combination with
other approaches; the results are validated
statistically and geologically. This allows a
quantification of geological features, which
can be utilised in the formation of geolog-
ical models. In addition, the integrative
analysis allows predictions of e.g. certain
mineralising systems. The predictions are
made from the relationships of data signa-
tures for sites with known mineralising
systems, which are used in the search for
similar signatures in unexplored areas.
Alternatively they come from a search for
specific data signatures and relationships,
which by comparison with established
mineral deposit models are found to be
characteristic of the mineralising system.
7
MINERAL RESOURCE ASSESSMENTS
The Storø Gold Prospect in the central part of Godthåbsfjord, southern West Greenland. Courtesy: NunaMinerals A/S.
Region
South Greenland
Southern West Greenland
Central West Greenland
North-West Greenland
North Greenland
East Greenland
Discovery
Metallogenetic province for gold and uranium
Kangerluluk gold occurrence
Stendalen copper-nickel-titanium occurrence
Illorsuit uranium occurrence
Kvanefjeld REE-uranium deposit
Motzfeldt Sø tantalum-niobium deposit
Fiskenæsset chromium occurrences
Ivisaatoq tungsten occurrences
Qussuk gold occurrence
Tikiusaaq carbonatite complex
Kangerluluk gold occurrence
Stendalen copper-nickel-titanium occurrence
Illorsuit uranium occurrence
Kvanefjeld REE-uranium deposit
Motzfeldt Sø tantalum-niobium deposit
Fiskenæsset chromium occurrences
Ivisaatoq tungsten occurrences
Qussuk gold occurrence
Tikiusaaq carbonatite complex
Sarfartoq niobium-REE-uranium occurrence
Attu gold occurrence
Eqi East gold occurrences
Saqqaq gold occurrence
Black Angle lead-zinc deposit
Attu gold occurrence
Eqi East gold occurrences
Saqqaq gold occurrence
Black Angle lead-zinc deposit
Melville Bugt iron province
`North Inglefield Land gold belt' Cu-Au occurrences
Minturn iron occurrence
Moriusaq titanium occurrence
Washington Land zinc-lead-silver occurrence
Navarana Fjord zinc-barite occurrence
`North Inglefield Land gold belt' Cu-Au occurrences
Minturn iron occurrence
Moriusaq titanium occurrence
Washington Land zinc-lead-silver occurrence
Navarana Fjord zinc-barite occurrence
Malmbjerg molybdenum deposit
Blyklippen lead-zinc deposit
Blyklippen lead-zinc deposit
Major discoveries made during public financed resource assessments
Integrative data analyses of this type have
successfully been used for e.g. gold oc cur -
rences in the Nuuk region, southern West
Green land. In this region, 69 different data -
set were used in cluding location of gold
occurrence and data from geological maps,
stream sediment geochemistry, aero mag -
netic data, aeroradiometric data and data
from lineament analyses. The integrative an -
alyses resulted in the identification of three
distinct groups of gold oc currences with dif-
ferent characteristic data signatures and data
relationships. Sta tis tically validated, predic-
tive prospectivity maps where constructed.
Several of the pre dicted most prospective
areas were subsequently investigated dur-
ing GEUS field work. In two out of six vis-
ited areas, geologists were able to confirm
a gold potential, based on sampling of rock
and/or sediments with elevated gold values.
rences in the Nuuk region, southern West
Green land. In this region, 69 different data -
set were used in cluding location of gold
occurrence and data from geological maps,
stream sediment geochemistry, aero mag -
netic data, aeroradiometric data and data
from lineament analyses. The integrative an -
alyses resulted in the identification of three
distinct groups of gold oc currences with dif-
ferent characteristic data signatures and data
relationships. Sta tis tically validated, predic-
tive prospectivity maps where constructed.
Several of the pre dicted most prospective
areas were subsequently investigated dur-
ing GEUS field work. In two out of six vis-
ited areas, geologists were able to confirm
a gold potential, based on sampling of rock
and/or sediments with elevated gold values.
The integrative data analyses are often
carried out in co-operation with other similar
international programmes. BMP and GEUS
are involved in for instance the `Global
Mineral Resource Assessment Programme'
carried out by the United States Geological
Survey, in which mineral resources in the
first kilometre of the crust are being esti-
mated. Similarly, there has been co-opera-
tion with the Canadian Geological Survey
and other international research groups.
are involved in for instance the `Global
Mineral Resource Assessment Programme'
carried out by the United States Geological
Survey, in which mineral resources in the
first kilometre of the crust are being esti-
mated. Similarly, there has been co-opera-
tion with the Canadian Geological Survey
and other international research groups.
Modern remote sensing
The high-tech development of instruments
for the acquisition of airborne and satellite
borne hyperspectral data and the improved
processing methods for such data have
lead GEUS, through EU and BMP projects,
to maximise the gain of remote sensing
data for mineral exploration purposes. It is
now common practice to use remote sens-
ing data from e.g. the Aster satellite to
prepare for coming field work, giving the
field geologists much more targeted infor-
The high-tech development of instruments
for the acquisition of airborne and satellite
borne hyperspectral data and the improved
processing methods for such data have
lead GEUS, through EU and BMP projects,
to maximise the gain of remote sensing
data for mineral exploration purposes. It is
now common practice to use remote sens-
ing data from e.g. the Aster satellite to
prepare for coming field work, giving the
field geologists much more targeted infor-
mation. The processing and interpretation
of remote sensing, especially hyperspectral
data, are based on the use of extensive
spectral libraries covering a range of inor-
ganic and organic natural materials. A
comprehensive library for Greenland has
been established and is being expanded
continuously. The results from processed
hyperspectral data have been used in the
search for kimberlites in central West
Greenland and have lately resulted in the
identification of a large anomaly that is
similar to the anomaly observed at the
well-known Malmbjerg molybdenum
deposit in central East Greenland.
of remote sensing, especially hyperspectral
data, are based on the use of extensive
spectral libraries covering a range of inor-
ganic and organic natural materials. A
comprehensive library for Greenland has
been established and is being expanded
continuously. The results from processed
hyperspectral data have been used in the
search for kimberlites in central West
Greenland and have lately resulted in the
identification of a large anomaly that is
similar to the anomaly observed at the
well-known Malmbjerg molybdenum
deposit in central East Greenland.
3-D geological modelling
Many years of geological research and
GEUS' extensive archives of data allow the
construction of digital 3-D geological
models of mineralising system, regional
geological structures and overall crustal
Many years of geological research and
GEUS' extensive archives of data allow the
construction of digital 3-D geological
models of mineralising system, regional
geological structures and overall crustal
8
GEOLOGY AND ORE 15 / 2009
MINERAL RESOURCE ASSESSMENTS
Extensive zone with hydrothermal alteration and mineralisation south of Ameralik, southern West Greenland, visited by GEUS geologists during the
mineral resource assessment programme in 2008.
mineral resource assessment programme in 2008.
9
MINERAL RESOURCE ASSESSMENTS
Simplified geological maps with the top rated 137 km
2
(1% of the analysed
area) outlined as most gold favourable area for the three groups of gold
showings (Isua, Bjørneøen and Storø groups). Outlines of the rock units are
from digital versions of 1:100 000 and 1:2 500 000 scale geological maps
published by GEUS.
showings (Isua, Bjørneøen and Storø groups). Outlines of the rock units are
from digital versions of 1:100 000 and 1:2 500 000 scale geological maps
published by GEUS.
Data
No. of showings
Gold showings
Au = known
gold showing
gold showing
No showings
Empirical distribution
functions are calculated
for different datasets one for
'showings', one for 'no showings'.
functions are calculated
for different datasets one for
'showings', one for 'no showings'.
?
?
?
? ? ? ? ? ? ? ? ? ?
?
?
?
? ? ? ? ? ?
? ? ?
?
?
?
? ? ? ? ? ? ? ? ? ?
? ?
? ? ? ? ? ? ? ? ? ?
?
?
?
? ? ? ? ?
? ? ? ?
?
?
?
? ? ? ? ? ? ? ? ? ?
?
?
?
Quantified signatures
in different datasets
A search for similar signatures
is carried out.
The degree of similarities is
used to construct mineral
potential maps.
is carried out.
The degree of similarities is
used to construct mineral
potential maps.
Mineral potential map
high
low
Favourability for gold showings
Geoscientific datasets are pixelated
2
1
4
3
Au
Au
Au
Fiskefjord
Inland
Ice
Davis
Strait
Godthåbsfjord
Godthåbsfjord
Ameralik
Qooqqut
Nuuk
region
Q
A
64°30'N
65°N
52°W
51°W
Isukasia
Q
A
Q
A
50°W
Sermitsia
q
Nuuk
Storø
Bjørneøen
Ivisaartoq
25 km
Gneiss
Ice
Amphibolite
Metasediment
Ultramafic rock
Metasediment
Ultramafic rock
Fault and shear zones
Late Archaean granites
Storø showings
Bjørneøen showings
Isua showings
Ungrouped showings
Isua gold group
The top 137 km most
favourable areas for:
favourable areas for:
2
Bjørneøen gold group
Storø gold group
Illustration of the principal steps in a statistical approach to mineral
potential mapping:
potential mapping:
1: Regional datasets and gold showings (Au) are referred to a
common grid with fixed cell size: a pixel.
2: Empirical distribution functions for pixels with and without
known gold showings are used to establish the signatures of
the showings in each dataset.
the showings in each dataset.
3: RatiOFunctions for all datasets are calculated on the basis of
the two previous functions, expressing the likelihood of a
showing. Groupings of gold showings are based on con-
structed mineral potential maps for each showing. Pixel by
pixel, these maps outline the predicted favourability for data
signatures similar to the selected showing, i.e. the potential
for a similar showing.
showing. Groupings of gold showings are based on con-
structed mineral potential maps for each showing. Pixel by
pixel, these maps outline the predicted favourability for data
signatures similar to the selected showing, i.e. the potential
for a similar showing.
4: Finally, mineral potential maps are calculated for each identi-
fied group of showings. These maps are based on the signa-
tures found to be indicative for each of the different groups.
tures found to be indicative for each of the different groups.
Principles of mineral potential mapping
composition. As mineral deposit models
advance and data analyses improve 3-D
visualisation and interpretation becomes
more important. Furthermore, with a few
exceptions, only the geology ex pressed
near the surface has been searched for
mineral deposits in Green land. As the
exploration and mining industry deepens
the search for concealed de posits, the sub-
surface never-explored Greenland and
thus the future 3-D geological models in
the mineral resource assessments will be
of greater importance.
advance and data analyses improve 3-D
visualisation and interpretation becomes
more important. Furthermore, with a few
exceptions, only the geology ex pressed
near the surface has been searched for
mineral deposits in Green land. As the
exploration and mining industry deepens
the search for concealed de posits, the sub-
surface never-explored Greenland and
thus the future 3-D geological models in
the mineral resource assessments will be
of greater importance.
10
GEOLOGY AND ORE 15 / 2009
MINERAL RESOURCE ASSESSMENTS
Perspective view of the Malmbjerg molybdenum deposit seen from the south-west, no vertical
exaggeration (granite stock indicated by the dotted line).
Upper: Colour composite of HyMap data R (band 28), G (band 18), B (band 2) draped on the ter-
rain model. The granite stock is surrounded by a zone of propylitic alteration (`Gelbe Rinne', red =
illite and goethite; yellow = jarosite).
Lower: Colour composite of transformed shortwave, infrared HyMap reflectance, illustrating the
exposure of the Mo-mineralised granite. Note the extent of the hydrothermally altered wallrocks
(hues of yellow and orange). The roof zone of the granite stock is characterised by the greisen
developments as outlined by topaz-enriched rocks (white).
exaggeration (granite stock indicated by the dotted line).
Upper: Colour composite of HyMap data R (band 28), G (band 18), B (band 2) draped on the ter-
rain model. The granite stock is surrounded by a zone of propylitic alteration (`Gelbe Rinne', red =
illite and goethite; yellow = jarosite).
Lower: Colour composite of transformed shortwave, infrared HyMap reflectance, illustrating the
exposure of the Mo-mineralised granite. Note the extent of the hydrothermally altered wallrocks
(hues of yellow and orange). The roof zone of the granite stock is characterised by the greisen
developments as outlined by topaz-enriched rocks (white).
Gelbe Rinne
Alteration of roo ng rocks
Malmbjerg
granite stock
Hydrothermal alteration zones north of Buksefjorden visited by GEUS geologists during field work in 2008. Two soil samples from the area run 107
and 378 ppb Au respectively. A potential for gold in this area has until now not been known.
and 378 ppb Au respectively. A potential for gold in this area has until now not been known.
GO_15.qxp:GO-02 copy.qxp 2/11/09 10:51 AM Page 10
Future prospects
The content of this magazine shows the
involvement of public authorities in the
development of the mining industry. The
authorities have spent many man-years
and funds to ease the way for the explo-
ration industry, providing easy access to
data, knowledge and geological know-
how accumulated over the generations.
Soon the new Self-Governance of
Greenland will be a fact and the success-
ful and safe use of natural resources will
remain a central topic for Greenland society.
involvement of public authorities in the
development of the mining industry. The
authorities have spent many man-years
and funds to ease the way for the explo-
ration industry, providing easy access to
data, knowledge and geological know-
how accumulated over the generations.
Soon the new Self-Governance of
Greenland will be a fact and the success-
ful and safe use of natural resources will
remain a central topic for Greenland society.
11
MINERAL RESOURCE ASSESSMENTS
A GEUS geologist performs digital data capturing of field observations during the Survey's mineral assessment programme in 2008, 75 km east of
Buksefjord, southern West Greeenland.
Buksefjord, southern West Greeenland.
Three-dimensional geological model of the Skaergaard layered intrusion in East Greenland a potential
world-class, multi-element deposit with the main commodities being PGEs and Au. The digital elevation
model is draped with Aster scenes. The outline of the intrusion is indicated. Locations of drill holes
released to the public are shown in blue. One of the modelled bowl-shaped, PGE-bearing layers (Pd5)
within the layered intrusion is shown in green. The green line indicates the outline of the intrusion at
the surface. 200 m contour lines are in red. Modelling by GEUS.
world-class, multi-element deposit with the main commodities being PGEs and Au. The digital elevation
model is draped with Aster scenes. The outline of the intrusion is indicated. Locations of drill holes
released to the public are shown in blue. One of the modelled bowl-shaped, PGE-bearing layers (Pd5)
within the layered intrusion is shown in green. The green line indicates the outline of the intrusion at
the surface. 200 m contour lines are in red. Modelling by GEUS.
GO_15.qxp:GO-02 copy.qxp 2/11/09 10:51 AM Page 11
12
GEOLOGY AND ORE 15 / 2009
Key literature
Appel, P.W.U., Garde, A.A., Jørgensen, M.S.,
Moberg, E., Rasmussen, T.M., Schjøth, F. &
Steenfelt, A. 2003:
Economic potential of the
greenstone belts in the Nuuk area. General geol-
ogy and evaluation of compiled geophysical,
geochemical and ore geological data. Danmarks
og Grønlands Geologiske Undersøgelse Rapport
2003/94
, 140 pp. + DVD. (Price: DKK 700.)
Jensen, S.M., Secher, K., Rasmussen, T.M. &
Schjøth, F. 2004:
Diamond exploration data from
West Greenland: 2004 update and revision. Dan -
marks og Grønlands Geologiske Undersøgelse
Rapport
2004/117
, 90 pp. + DVD. (Price: DKK
1000.)
Pedersen, M. 1999:
GIS compilation of geoscience
data: an ArcView GIS version of partly unpublished
data from Wegener Halvø, central East Greenland.
Danmarks og Grønlands Geologiske Undersøgelse
Rapport
1999/37
, 14 pp. + CD-ROM. (Price: DKK
300.)
Rasmussen, T.M., Thorning, L., Stemp, R.W.,
Jørgensen, M.S. & Schjøth, F. 2001:
AEM
Greenland 19941998summary report. Dan -
marks og Grønlands Geologiske Undersøgelse
Rapport
2001/58
, 46 pp. + CD-ROM. (Price: DKK
300.)
Schjøth, F. & Thorning, L. 1998:
GIS compila-
tion of geoscience data: an ArcView GIS version
of previously published thematic maps from
Inglefield Land, North-West Greenland. Danmarks
og Grønlands Geologiske Undersøgelse Rapport
1998/107
, 59 pp. + CD-ROM. (Price: DKK 300.)
Schjøth, F. & Steenfelt, A. (eds) 2004:
Mineral
resources of the Precambrian shield of central
West Greenland (66° to 70°15´N). Part 1.
Compilation of geoscience data. Danmarks og
Grønlands Geologiske Undersøgelse Rapport
2004/16
, 45 pp. + appendices and DVD. (Price:
DKK 700.)
Schjøth, F., Garde, A.A., Jørgensen, M.S., Lind,
M., Moberg, E., Nielsen, T.F.D., Rasmussen,
T.M., Secher, K., Steenfelt, A., Stendal, H.,
Thorning, L. & Tukiainen, T. 2000:
Mineral
resource potential of South Greenland: the CD-
ROM. Danmarks og Grønlands Geologiske
Undersøgelse Rapport
2000/57
, 36 pp. + CD-
ROM. (Price: DKK 1000.)
Steenfelt, A. 2001:
Geochemical atlas of Green -
land West and South Greenland. Danmarks og
Grønlands Geologiske Undersøgelse Rapport
2001/46
, 39 pp. incl. maps or CD-ROM. (Price:
DKK 300.)
Steenfelt, A., Thorning, L & Tukiainen, T. (eds)
1990:
Regional compilations of geoscience data
from the NuukManiitsoq area, southern West
Greenland. Thematic Map Series Grønlands
Geologiske Undersøgelse
90/1
, 9 pp., 57 maps.
(Price: DKK 2600.)
Stendal, H., Nielsen, B.M., Secher, K. &
Steenfelt, A. 2004:
Mineral resources of the
Precambrian shield of central West Greenland
(66° to 70°15´N). Part 2. Mineral occurrences.
Danmarks og Grønlands Geologiske Undersøgelse
Rapport
2004/20
, 212 pp. (Price: DKK 350.)
Tukiainen, T. 2006:
Mapping of kimberlitic rocks
in central West Greenland using airborne hyper-
spectral data. Danmarks og Grønlands Geologiske
Undersøgelse Rapport
2006/68
, 30 pp. + DVD.
(Price: DKK 450.)
Tukiainen, T. & Krebs, J.D. 2004:
Mineral resources
of the Precambrian shield of central West
Greenland (66° to 70°15´N). Part 4. Mapping of
kimberlitic rocks in West Greenland using air-
borne hyperspectral data. Danmarks og Grønlands
Geologiske Undersøgelse Rapport
2004/45
, 39
pp. + appendices and DVD. (Price: DKK 600.)
Front cover photograph
Assessment of iron-sulphide accumula-
tion in the Ivisaartoq Greenstone Belt,
inner Godthåbsfjord, southern West
Greenland.
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
Authors
Bo Møller Stensgaard &
Leif Thorning, GEUS
Editor
Karsten Secher, GEUS
Graphic Production
Carsten E. Thuesen, GEUS
Photographs
GEUS unless otherwise stated
Printed
February 2009 © GEUS
Printers
Schultz Grafisk
ISSN
1602-818x
Field registration of kimberlite dyke in the
Maniitsoq area, southern West Greenland.
Maniitsoq area, southern West Greenland.
Field registration of kimberlite dyke in the
Maniitsoq area, southern West Greenland.
Maniitsoq area, southern West Greenland.
Last modified: January 26, 2009
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