An evaluation of the potential for uranium deposite in Greenland

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An evaluation of the potential for uranium deposite in Greenland

Executive Summary

This report outlines the potential for uranium deposits in  Greenland. As a result of this assessment, it is shown that the most prospective types of uranium mineralisations in Greenland are the sandstone type, unconformity-related type, quartz pebble conglomerate type,

vein type, intrusive type, volcanic type, and metasomatite type occurences. The areas with a high potential are displayed in Figure 1. In addition to the well-known uranium province in South-Greenland, several areas along the western coast, the Thule Basin in North-West Greenland and central East Greenland are considered to have a high uranium potential.

South Greenland is the area that has been investigated in most detail previously, and it is probably also the area with the highest potential to find uranium deposits. In particular the uranium occurrences and showings that are hosted by intrusive rocks and veins related to the Gardar intrusive complex and by the sandstones of the psammite zone have a very high potential. In addition, the basal unconformity of the Eriksfjord Formation in the Gardar province has a high potential to host a uranium deposit. In the psammite zone, the positive indications to host a typical sandstone deposit in combination with a strong metamorphic overprint, which led to partial melting associated with veining and formation of leucogranitic bodies, leave the whole area as a high potential target. The conglomerates of Midterrnæs and Grænseland have not been extensively investigated, but are considered good target areas too.

Southern West Greenland has been relatively well studied previously. In this region the uranium potential is mainly represented by carbonatite intrusions. Especially Sarfartoq and Qaqarssuk carbonatites have a high potential.

Further to the north on the western coast three potential areas have been indicated where chances to find a uranium deposit are good. These include (1) the Archaean and Palaeoproterozoic sediments with quartz pebble conglomerates on southern Nuussuaq and in the Ataa domain; (2) the conglomerates of the Karrat Group; and (3) the sandstones and the basal contact of the Cretaceous and Paleogene sediments of the Nuussuaq Group that are partially derived from these Precambrian metasediments and were deposited intercalated with coal deposits on western Nuussuaq and on Disko Island.

The Thule Supergroup in North-West Greenland has a very high potential as a sandstone deposit and as an unconformity-related deposit. Furthermore quartz-pebble conglomerates occur in the same area; these might also have some potential to host a uranium deposit. The area has not been investigated very intensively for uranium in previous studies, and might form an interesting target.

Central East Greenland hosts a range of felsic to alkaline intrusive complexes that range from Proterozoic to Palaeogene in age. These outcrops make good targets for uranium deposits, especially the Caledonian and 950-900 Ma intrusive rocks, together with the volcanic rocks and veins in the area. The best known example from this area is Randbøldal. Central East Greenland also hosts a thick series of Mesozoic sandstones, which make another good target for exploration.