粤东花岗岩及锡、钨矿床的地球化学研究

粤东燕山期与成矿有关的火成岩主要有早、晚两期,分别由火山岩与二长花岗岩及火山岩与黑云母花岗岩组成,两期的火山岩与花岗岩之间均为部分熔融关系,早期火成岩的源岩以沉积岩为主,晚期火成岩以火成物质占优势。锡矿化可划分为锡石—石英期次、锡石—硫化物期次及硫化物—银、金—碳酸盐期次;钨矿化可分为黑钨—石英期次,白钨—硫化物期次及碳酸盐期次。据系统的矿物包裹体,成矿热力学、成因矿物学、微量元素及同位素地球化学研究表明其成矿流体及成矿物质主要来自花岗岩,锡的矿化与早期二长花岗岩有关,钨矿化与晚期黑云母花岗岩关系密切。矿床成因类型应属岩浆—热液矿床。

GEOCHEMICAL STUDIES ON TIN AND TUNGSTEN DEPOSITS AND GRANITOID IN EASTERN GUANGDONG

The Yenshannia igneous rocks in eastern Guangdong can be devided into two periods, during the earlier Yenshannia period being volcanic rocks and admellite, and during the later Yenshannia period volcanic rocks and biotite granites. Geochemical studies show that all the igneous rocks formed by partial melting, and that the earlier volcanic rocks and admellite were the successive melting products of the same source rocks but in different depths and melting degrees , and so were the later volcanic rocks and biotite granites. The source rocks of the earlier volcanic rocks and admellite were mainly sedimentary rocks , and those of the later volcanic rocks and biotite granites were mantle substance , that is , magmatic rocks of mantle origin which had previously existed in the crust . The Tin mineralizations include Cassiterite-Quartz stage , Cassiterite-Sulfide Stage and Sulfide-Silver , Gold-Cabbonate stage . The Tungsten mineralizations include Wolframite-quartz Stage, Soheelite-Sulfide stage and Carbonate stage. Systematic studies on fluid inclusions , thermodynamics , genetic mineralogy , geochemistry of trace elements and isotopes show that the mineralizing fluids and the ore-forming elements in these deposits came mainly from the granitoids . Tin mineralizations are releted to the earlier Yenshannia admellitic magmatic activity , and Tungsten mineralizations to the later Yenshannia biotite granitic magmatic activity . They belong to magmatic hydrothermal deposits .