GEOLOGY AND COPPER SULPHIDE MINERALIZATION OF THE SALMAGORSKII RING IGNEOUS COMPLEX, KOLA PENINSULA, NW RUSSIA

Abstract

The Salmagorskii igneous complex represents a rare example of peralkaline rocks containing significant copper sulphide mineralization presented by chalcopyrite, djerfisherite and cubanite. Data on the geological structure of the complex and the copper sulphide–apatite mineralization related to its foidolitic peralkaline rocks have been obtained from drilling in recent years. The sequence of rocks (dunite–clinopyroxenite–melilitolite–ijolite–urtite–melteigite–carbonatite) forms a perfect concentric zoning within the pluton indicating that fractional crystallization was the predominant petrogenetic process. Copper sulphide mineralization formed at the post-magmatic stage, when recrystallization processes within earlier ijolite and melteigite took place under the influence of a fluid rich in CO2, H2O, alkalis, S, P, Cu, and Cl.