Vaikijaur, an intrusion hosted, porphyry style, Palaeoproterozoic Cu-Au mineralization at the Archaean―Proterozoic boundary in northern Sweden

摘要

The Vaikijaur copper-gold mineralization is hosted by the Jokkmokk granitoid, which was emplaced at 1.89―1.88 Ga, close to the Archaean―Palaeoproterozoic boundary in northern Sweden. The Jokkmokk granitoid is a calc-alkaline quartz diorite-tonalite-granodiorite formed in a volcanic arc environment. Positive Eu-anomalies are characteristic for the mineralized part of the pluton. Several stages of alteration are recognized based on chemical and mineralogical analyses. The alteration zones, the stockwork, veinlets, and disseminations suggest that the copper-gold mineralization is formed by magmatic hydrothermal fluids. These fluids may have been derived from a comagmatic mafic pluton at depth.