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桐村地区与德兴矿区岩石系列相似,为高钾钙碱性系列;在岩石结构上,桐村地区花岗闪长岩为似斑状结构,德兴矿区花岗闪长斑岩为斑状结构。两者均为钙碱—碱质镁质I型花岗岩。桐村岩石富Si和K,A/CNK和K/(K+Na)值均小于德兴岩石。微量元素、同位素及岩石学特征表明桐村地区的物质来源以壳源为主,而德兴地区为有大量幔源物质参与的壳幔混合型,其原因可能与两区不同的构造位置有关。中晚侏罗世时,太平洋板块西向俯冲,下插板片发生部分熔融形成的岩浆与岩石圈地幔楔发生作用从而形成斑岩岩浆是桐村和德兴地区可能的成因模式。桐村矿床含矿斑岩的氧逸度、演化程度和地壳混染程度均较德兴斑岩铜矿高。对于同时代、近距离的岩浆岩形成如此规模悬殊的矿床还有许多问题值得研究和思考。
The Tongcun area is similar to the Dexing mining area rock series, and is a high-K calc-alkaline series. On the rock structure, the Tongdian granodiorite is plaque-like structure, and the Dexing mining area is a granodiorite porphyrite structure. Both are calc-alkaline-magnesian type I granites. Tongchuang rocks are rich in Si and K, A / CNK and K / (K + Na) values less than Dexing rocks. The trace elements, isotopes and petrologic characteristics indicate that the source of the material in the Tongcun area is mainly the crust, while the Dexing area is the crust-mantle mixed type with a large amount of mantle-derived materials, which may be related to the different tectonic positions in the two areas. During the Middle-Late Jurassic, the magmatic lava formed by partial melting of the Pacific plate and the mantle wedge of the lithosphere play a role in the formation of porphyry magma and are the possible generative models in Tongcun and Dexing areas. The oxygen fugacity, the degree of evolution and the degree of crustal contamination of ore-bearing porphyries in Tongcun deposit are both higher than that of Dexing porphyry copper deposit. For the contemporary, close-range magmatic rocks to form such a disproportionate deposit there are many problems worthy of study and reflection.