Petrology of the Meliadine kimberlite dykes, District of Keewatin, Northwest Territories, Canada

arren kimberlite dykes were discovered in three separate diamond drill holes during 1996 on the Meliadine gold property, District of Keewatin, Northwest Territories, Canada. These dykes are situated within the supracrustal rocks of the ca. 2.66 Ga Rankin Inlet Group Churchill Province. The dykes are best classified as kimberlite based on mineralogy, mineral chemistry, major and trace element whole-rock geochemistry, and Sr-Nd isotopic compositions. All dykes display characteristics of evolved carbonate-rich kimberlites, as they are characterized by high amounts of carbonate, scarcity of mantle-derived megacrysts, general lack of Cr-bearing spinels, and abundance of Ti-rich spinels.;U-Pb geochronology on two perovskite fractions from selected dykes yielded an Early Jurassic...