Geology and Ore 14, 2024

Plutonic environments in Greenland – a potential for new discoveries

Mineral deposits of plutonic complexes are among the most promising exploration targets in Greenland. Examples are the Malmbjerg molybdenum deposit, the Skaergaard intrusion gold and platinum group element deposit and the Ilimaussaq zirconium, rare earth element (REE), thorium and uranium deposit. They are all three explored at present and have the potential to become large mining operations. However, many plutonic and hypabyssal provinces in Greenland are still signifcantly under-explored.

In 2002, GEUS published an overview of all the intrusive complexes in the Palaeogene province in East Greenland (GEUS report, 2002/113). The overview includes basic information and metadata on all the complexes allowing easy access to the basic geological data and non-confdential exploration records. The Palaeogene province in East Greenland is only one out of 23 defned plutonic provinces within the Archaean to Neogene evolution in Greenland. Basic geological data and exploration information on all plutons, sill complexes and dyke swarms in these provinces can be conveniently accessed on the Greenland Portal, at www.greenmin.gl. This issue of ‘Geology & Ore’ deals with the 23 plutonic provinces in summary outline.

Introduction

Intrusive rocks are an integrated part of the geological evolution of Greenland, and provinces of plutons and hypabyssal rocks can be defned in most geological periods. Table 1 lists all provinces in which the plutons, sills and dykes have preserved clear intrusive features and spatial integrity. The provinces are listed according to geological period, from Palaeogene to Archaean, and subsequently clockwise along the coast of Greenland starting in North-East Greenland.

The identifcation number and the province are given in columns 1 and 2. Column 3 gives the main rock types and minor comments, column 4 gives examples of the most important commodities recorded within the province, and column 5 gives a suggestion for the geodynamic environment of the province. The four maps show the Palaeogene, the Mesozoic and Palaeozoic, the Proterozoic, and the Archaean provinces.