宝山—香花岭一带岩浆岩的稀土元素特征

在湘南著名的Cu、Pb、Zn、Sn多金属成矿区——宝山至香花岭一带,燕山期岩浆岩发育,成群成带展布。由北往南分别有宝山岩带、黄沙坪岩群和香花岭岩群,岩性由中性向酸性过渡。稀土元素分布特征表明:北边的宝山岩带可能是下部地壳物质批式熔融上侵产物,在上侵过程中可能经历过不同程度的分离结晶作用;南边的香花岭岩群可能是上部地壳物质重熔岩浆经分离结晶分异的产物;而中间的黄沙坪岩群则可能是重熔岩浆与下部地壳部分熔融初始岩浆混合后上侵再经结晶分异的产物,该区由北往南出现Cu—Pb、Zn—Sn的成矿分带是不同岩浆成矿专属性的体现。

RARE EARTE ELEMENT FEATURES OF THE MAGMATIC ROCKS ALONG A ZONE FROM BAOSHAN TO XIANGHUALING

In the area from Baoshan to Xianghualing, the famous Cu-Pb-Zn-Sn polymetallic metallogenic zone in southern Hunan, the magmatic rocks of Yanshanian period were well-developped which occurred in groups and zones. There are from north to south Baoshan rock belt, Huangshaping intrusive swarm and Xianghualing stock swarm, and their lithology shew transition from medium to acidic. The distribution of rare earth element shows that the Baoshan rock belt in the north probably results from the batch melting of lower Crust material, which may have undergone fractional crystallization of varying degrees in the upward intruding process; the Xianghualing stock swarm in the south may be the products of fractional crystallization differentiation of upper Crust remelting magma; while Huangshaping intrusive swrm in between may result from fractional crystallization of the mixed magma of lower Crust derived initial batch melting magma with upper Crust material remelting magma, The metallogenic zoning of Cu-Pb, Zn-Sn from south to north in this region is the incarnation of the metalloeenic specialization of different mammas.