The sources of large and unique platinum-metal placers were the zonal alkali-ultrabasic massifs be- coming active in the Cretaceous time that gravitated to the periphery of the areal of the North-Asian Superplume (NA...The sources of large and unique platinum-metal placers were the zonal alkali-ultrabasic massifs be- coming active in the Cretaceous time that gravitated to the periphery of the areal of the North-Asian Superplume (NAS) influence. Origin of the conditions favorable for the formation of the placer platinum presence in the re- gion is governed by the plume ore-generating magmatism of several generations ( in Proterozoie and Phanerozo- ic). Ultramafite-mafite magmatism was responsible for the origin of the stratified zonal massifs subjected in the Late Paleozoic and Mesozoic to the action of granitogene derivations of the NAS. The latter provided the devel- opment of the ore-forming magmagene-fluid-metasomatic processes and favorable conditions for the platinum group elements concentration.展开更多
文摘The sources of large and unique platinum-metal placers were the zonal alkali-ultrabasic massifs be- coming active in the Cretaceous time that gravitated to the periphery of the areal of the North-Asian Superplume (NAS) influence. Origin of the conditions favorable for the formation of the placer platinum presence in the re- gion is governed by the plume ore-generating magmatism of several generations ( in Proterozoie and Phanerozo- ic). Ultramafite-mafite magmatism was responsible for the origin of the stratified zonal massifs subjected in the Late Paleozoic and Mesozoic to the action of granitogene derivations of the NAS. The latter provided the devel- opment of the ore-forming magmagene-fluid-metasomatic processes and favorable conditions for the platinum group elements concentration.