Geochemical Characteristics of Some Rare Element-bearing Granites in Southeast China and Physico-chemical Conditions of Their Formation

The formation of ore-bearing granites in the Yenshanian movement in southeast China andthe geochemical characteristics of some RE-bearing granites have been studied throughmultivariate statistical analysis and physicochemical approach. The main conclusions have beendrawn as follows: （1） The granites are beieved to be products of anatexis of the crustal ma-terials. The formation temperature of granitic magma is estimated at about 600℃ and thecrystallization temperatures range from 600°to 500℃. The temperature of Li-, F- and H;O-rich residual magma in the latest stage of magmatism is probably below 500℃. （2） A rockseries from early lepidomelane-granite through protolithionite- and zinnwaldite-granite to lithio-nite- or lepidolite-granite is considered as a result of actual crystallization. （3）The mineral pa-ragenesis and facies zonation of granite plutons are mainly controlled by PH;o,μNa;O and μK;Oin the magma. （4）During the magmatic evolution the ore-forming elements（REE, Nb, Ta,etc.） are variable in geochemistry. REEs, similar to mafic components, were highly concentra-ted at the early stage of the magmatic evolution and deposited under favourable conditionsin the zinnwaldite- and protolithionite-granites; Nb and Ta have a preference for felsic andvolatile components, thus are mainly concentrated at later stages of the magmatic evolution. Nbore deposits are formed in the lithionite and lepidolite granites. for Ta is intimately associatedwith Na;O,Li;O, F and H;O.