Orogenic gold mineralisation in the Archean North Atlantic craton, southern West and South-West Greenland

The North Atlantic craton of Greenland has no producing gold mine, although Archean rocks represent the entire time span from > 3.6 Ga until ca. 2550 Ma and major accretionary tectonics affected the craton in the Neorchaean. In the recent years, gold exploration in the Godthåbsfjord has identified several gold targets, the most advanced being the Storø and Qussuk gold prospects. In this paper, we present an overview of known and recently discovered orogenic gold occurrences and link their genesis with the regional geological evolution.

The North Atlantic craton is divided into several terranes and blocks, with a complex tectono-metamorphic and magmatic history. The terranes and blocks comprise belts of supracrustal rocks and/or anorthosite complexes that are intruded by TTG gneiss and minor volumes of late-tectonic granites. The rocks are metamorphosed at amphibolite facies to granulite facies grades. Greenschist facies metamorphism is restricted to localities around Isua and the Tartoq Group in the south. Several terrane accretion events are recorded at ca. 2950 Ma, 2840-2830 Ma, 2760-2740 Ma, 2720-2700 Ma and 2670-2600 Ma. As Archean orogenic gold deposits are known to having formed during accretionary tectonics mainly between 2720 Ma and 2620 Ma, the so called “golden window”, the region should be suitable for hosting this deposit type.