与碱性玄武岩有关刚玉巨晶的多阶段成因──包裹体的证据

The Forming of Corundum Megacrysts Related to Alkali Basalt in Changle,Shandong

分析山东昌乐与碱性玄武岩有关的刚玉巨晶不同部位的常量元素、稀土元素及包裹体组成 .刚玉巨晶的主体以大量流体—熔体包裹体、锆石、铌 (钽 )铁矿包裹体为主 ,而巨晶中的“晶核”部位则以大量的熔体包裹体为主 ,反映研究区的刚玉巨晶是在不同的阶段形成的 .刚玉“晶核”以及“铜皮刚玉”形成于熔体相为主的体系中 ,而主体刚玉则形成于熔体—流体过渡的急剧变化的不均一的地球化学环境中 .

The compositions of usual elements and rare earth elements and inclusions of corundum megacrysts related to alkali basalt in Changle,Shandong Province,are analyzed.In the main parts of corundum megacrysts are a large number of fluid\|melting inclusions,zircon,Ta\|columbite inclusions,and in the central crystal core are a large number of melting inclusions.The corundum megacrysts were formed in different periods and different physical chemistry conditions.The crystal core was formed in magma system,and the main parts were formed in inhomogeneously geochemical conditions in which magam and fluid phases coexisted.