Geology and Ore 31, 2018

Magmatic nickel potential in Greenland

A workshop on the ‘Assessment of the nickel potential in Greenland’ was arranged by the Geological Survey of Denmark and Greenland (GEUS) and the former Bureau of Minerals and Petroleum (BMP) on 27–29 November 2012. The purpose of the workshop was to assess magmatic komatiite-hosted, conduit- and contact-type nickel deposits, and also to assess the possible presence of undiscovered nickel deposits in Greenland in the uppermost part of the Earth’s crust and to rank the most prospective areas. The procedures for the assessment and ranking of the individual tracts were designed to comply, as much as possible, with the ‘Global Mineral Resource Assessment Project’ (GMRAP) procedures defined by the U.S. Geological Survey (USGS).

This edition of Geology and Ore highlights some of the results from the workshop, including descriptions of the most important nickel provinces in Greenland, their known mineralisations and the resulting potential for undiscovered nickel deposits within these provinces. A more comprehensive GEUS survey report documenting the results from the workshop has been published in the GEUS report series (Rosa et al. 2013).

Geology and Ore 31, 2018 is a revised version of number 24, 2013.

Introduction

The evaluation of the potential for undis-covered magmatic nickel deposits in Greenland was carried out according to the standardised process utilised in the GMRAP. In this process, an assessment panel of experts discuss all available knowledge and data for a specific area (tract) and assess the possibility of finding new undiscovered deposits within this tract. The assessment panel constituted nineteen geologists from the USGS, GEUS, the former BMP, University of Aarhus and private exploration companies; each with specific knowledge on aspects of Greenlandic geology and/or expertise in nickel deposits. Each tract was defined from the surface to 1 km depth (1.5 km for the conduit-type). The members of the assessment team made their individual estimates (bids) of the number of deposits of a specific size and grade they believed could be found and mined in a specific tract. A panel discussion of the bids led to a consensus bid, which was used as input to a statistical simulation. The result was a grade-tonnage estimate (prediction) of how much undiscovered ore and metal could be found within a tract under the best circumstances. The consensus bids and predicted number of undiscovered nickel deposits per tract are shown on page 5, 8 and 10.