Geology and Ore 16, 2009

Geological environments favourable for future mining

Shield formation and cratonisation in Greenland, created by the formation of continental and oceanic crust, occurred in Archaean time by the amalgamation of oceanic and new arc-formed crust following emplacement of tonalitetrondhjemite-granodiorite plutons. This was succeeded by orogenic deformation and greenschist to granulite facies metamorphism. At the same time during the Archaean period of huge crustal formation, major mineral deposits of gold and banded iron formations were developed in granitegreenstone terranes in southern West Greenland. Ultramafic to mafic intrusions in greenstone belts occurred in Greenland as major carriers of chromenickel-vanadium. From Palaeoproterozoic time, orogenic activity and rifting evolution created profound possibilities for the existence of viable economic occurrences. This is exemplified by magmatic and sedimentary environments in large scale, even gigantic, accumulations of commodities related to intrusions, fold belts and sedimentary basins.