Geology and Ore 26, 2015

Assessment of orogenic gold mineralisation in Greenland

An orogenic gold deposit has been mined at Nalunaq (South Greenland) from 2004 to 2013 when the operation was closed. A total of 10.65 tons (375,670 oz) of gold was produced during that period. In order to assess the potential for undiscovered orogenic gold deposits in Greenland, a workshop in Copenhagen (November 2014) investigated geological, geochemical and geophysical data. The main conclusion was that areas of South Greenland in relative proximity to the closed Nalunaq gold mine and the Archaean terranes of southern West and South- West Greenland have the highest potential for finding new orogenic gold deposits. The highlights from this workshop are presented here.

Introduction

known by mankind and has been extensively used and mined in the last 5,000 years. Gold is still the most important commodity in the mineral exploration industry, and approximately one third of the worldwide exploration investment is used to find gold deposits. Approximately half of the gold is used in jewellery and approximately one third is used as safe investment as many of the National Banks must hold a gold reserve. Only approximately 12% of the produced gold goes into industrial applications such as electronics, medicine and space craft.

The biggest current gold producers are China, Australia, USA, Russia and South Africa. Although gold is enriched in the Earth’s crust by different mechanisms forming different deposit types, orogenic gold deposits constitute 40% of the world’s gold resources.

In November 2014, a workshop on the ‘assessment of the orogenic gold potential in Greenland’ was arranged by the Geological Survey of Denmark and Greenland (GEUS) and the Ministry of Mineral Resources (MMR) - formerly Ministry of Industry and Mineral Resources to stimulate new gold exploration campaigns in Greenland. The purpose for the workshop was to assess the potential of undiscovered orogenic gold deposits in the upper 1 km of the Earth’s crust and to rank the most prospective areas. The methods for the assessment and ranking of the individual tracts were designed to comply with the ‘Global Mineral Resource Assessment Project’ procedures defined by the US Geological Survey (USGS).

This edition of Geology and Ore highlights the main results from the workshop, including descriptions of the most important orogenic gold provinces in Greenland. A recent geological review of orogenic gold provinces in southern West and South-West Greenland is given in Kolb et al. (2013), and a review on gold occurrences in South Greenland can be found in Stendal & Frei (2000). Other Geology and Ore volumes covering the description of orogenic gold mineralisation are nos. 1, 9 and 11. A comprehensive GEUS report documenting all results from the workshop will be available during 2015.

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