Литосфера (Apr 2016)
Composition and conditions of ilmenite and titanomagnetite ore formation in two-pyroxene gabbro of Medvedevskoe deposit (Southern Urals). II. Staging of ore genesis as a result of evolution of ore-bearing melt
Abstract
On the base of new petrochemical and geochemical data with specificity in the compositions of rock-forming and ore minerals was determined the conditions of formation of Ti-Fe-V mineralization in the two-pyroxene gabbro of Medvedevskoe deposit. Two stages of formation of abundant mineralization were distinguished. They occur in the rhythmically stratified amphibole-saussuritizated gabbro of early cumulatively-magmatic stage and in the late-magmatic (subsolidus) stage. Staging of ore-genesis during the late-magmatic phase is related to the non-equilibrium of residual fluidized melt enriched with water and chlorine to the previously extracted rock-forming and ore minerals (pyroxene, plagioclase, titanomagnetite and ilmenite) which formed a primary magmatic frame and layering of ore-bearing rocks.