Diamonds and lithospheric mantle properties in the Neoproterozoic igneous province of southern West Greenland

Abstract

The search for diamonds in Greenland has resulted in the discovery of many new dykes of kimberlite and ultramafic lamprophyre and, most importantly, in the acquisition of a wealth of chemical data on rocks and minerals representing mantle material entrained by the dyke magmas. The discovery of a diamondiferous sheet at Garnet Lake in southern West Greenland stimulated the research (Hutchison 2005). Over the past five to ten years, the Geological Survey of Denmark and Greenland together with the Bureau of Minerals and Petroleum in Greenland and international research groups have acquired, processed and interpreted data with the objective of identifying diamond-favourable regimes within the lithospheric mantle below the Archaean craton in West Greenland. Here we present mineral data from drift samples that allow us to identify where mantle conditions in terms of lithology and depth may be favourable for the occurrence of diamonds.