粤东中生代火山—侵入杂岩的地壳深熔成因——Pb-Nd-Sr多元同位素体系制约

Continental Crust Anatexite:the Genesis of Mesozoic Granitic Volcanic——Intrusive Complexes,Eastrn Guangdong——Constrains on Pb-Nd-Sr Multi-Element Isotopic Systems

本文根据系统的Pb-Nd-Sr多元同位素体系研究表明,粤东地区中生代花岗质火山—侵入杂岩成岩作用机制为壳源岩石的部分熔融作用。源岩为未出露的古老陆壳基底岩石,源岩物质组成不均一,为先存幔源火山岩和地壳沉积物的混合物或互层。

Eastern Guangdong Province is located at the southeast end of the NE volcanic belt of the coast of southeastern China. The Mesozoic volcanic—intrusive complexes crop out widely over the district. Based on studies of Pb-Nd-Sr multi-element isotopic systems,it is held in this paper that the rock-forming machenism on the granitic volcanic—intrusive complexes is anatexite (equilibrium partial melting) of the continental crust. The source rocks of the complexes are old basement rocks cropping out in the neighbouring eastern Fujian and Zhejiang, but in this region. The composition of the source rocks is not homogeneous, and is the mixed materials or interclay of crustal sediments and mantle volcanic rocks in the crust.