Massive sulphide sample from hole MQ-13-026 at the Imiak Hill occurrence, Maniitsoq Norite Belt (5.26% Ni, 1.78% Cu and 0.18% Co). Photo: North American Nickel Inc.

Sampling of nickel-copper sulphide mineralisation hosted within a metasedimentary sequence, associated with dioritic and ultramafic rocks at Tasiilaq, South-East Greenland. Photo: NunaMinerals A/S

Weathered boulder with disseminated and net-veined Ni-Cu-Co sulphides within dunite-dominated ultramafic sills at Ikertoq in West Greenland. Photo: 21st North.

Picrite lavas of the Vaigat Formation, Nuussuaq, central West Greenland. Photo: L. M. Larsen

Vibroseismic survey of deep conductive bodies, Disko Island. Photo: Avannaa Resources

Vibroseismic survey of deep conductive bodies, Disko Island. Photo: Avannaa Resources

 Major nickel occurrences

The nickel potential in Greenland is related to mafic to ultramafic magmatism, which can be associated with komatiite-hosted occurrences, contact-type occurrences and conduit-type occurrences related to picritic and/or tholeiitic basalt dyke/sill complexes. Tracts with potential to host these occurrences, which extend from the Archean to the Palaeogene, were evaluated during a mineral potential assessment workshop, following USGS guidelines, held in 2012.

Interactive GIS-map of Nickel Occurrences

Archean

Archean nickel mineralisation is represented by conduit-type occurrences such as those in the Maniitsoq norite belt, which has been suggested surrounds a ca. 3.0 Ga large impact structure that triggered fracturing and magma ascension. Crustal contamination of mafic to ultramafic magmas has resulted in the accumulation of several conductive sulphide bodies, which were identified through geophysics and subsequently tested through over 130 drillholes to date. Other Archean nickel conduit-type occurrences include those in the Qeqertarssuatsiaq area of the Fiskenæsset metamorphosed layered igneous complex in West Greenland, where accumulation of chromite and to a lesser degree of Ni-rich sulphide segregations within a bronzitite layer have been described.
Archean komatiite-hosted occurrences are known from the Ikertoq (part of the Niaqornarssuit ultramafic complex near Kangerlussuaq), Nuuk-Akia and Bjørnesund areas in West Greenland.

Proterozoic

The geological environment hosting the Voisey´s Bay deposit in Canada, continues across the Davis Strait into the Greenlandic Nagssugtoqidian Orogen, which has therefore been the focus for nickel exploration. This orogen can be traced under the ice cap to the eastern coast of Greenland, as the Ammassalik mobile belt, where nickel sulphide mineralized lenses have been observed along several kilometres along the contacts of  three dioritic centres of the Ammassalik Igneous Complex near Tasiilaq, South-East Greenland. Conduit-type nickel occurrences can also be found in Gardar dykes of the Palaeoproterozoic Ketilidian orogen at the southern border of the Archean craton.

Komatiite-hosted nickel mineralization has also been reported in komatiite pods or boudins in  Palaeoproterozoic supracrustal rocks surrounding the Ammassalik Igneous Complex, in South-East Greenland.

Palaeogene

Flood basalt provinces in East Greenland and in West Greenland, record major magmatic activity, and cover areas of more than 65,000km² and 68,000 km², respectively. Their numerous dyke and sill systems, are generally viewed as having a promising potential for nickel accumulation. Known conduit-type nickel occurrences are mainly hosted in presumably sediment- contaminated lavas and dykes at the base of the basalt sequence in the Disko-Nuussuaq region of West  Greenland. Potential for contact-type nickel mineralization has been identified in the Kap Edvard Holm Complex, in South-East Greenland, a large layered tholeiitic gabbro complex intruding sulfur-rich sedimentary rocks.

Contact person: Diogo Rosa Email: dro@geus.dk

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