粤北贵东复式岩体的形成与重熔界面的形态演化

根据花岗岩的“原地重熔 壳内对流”理论,对粤北贵东复式岩体的各种地质地球化学资料进行重新编码,证实该复式岩体的形成是该区陆壳中生代多次熔融(重熔)的结果,并在此基础上重建该区不同期次重熔界面形态。研究表明,早侏罗世重熔界面总体自南向北倾斜,因而在同一剥蚀面下,岩体自南向北依次出露中心相、过渡相、边缘相的岩性;晚侏罗世的熔融(重熔)事件基本局限于早期岩体内部,故该期岩体普遍比早期岩体偏酸性,本期岩浆界面自北向南倾斜。早白垩世的熔融(重熔)事件形成了石英正长岩和次英安斑岩两类不同的岩石,两者岩性的较大差异与卷入的源岩有关,本期的重熔界面同样自北向南倾斜,据此进行的隐伏矿床预测已经获得验证。

Formation mechanism of the Guidong CGB in North Guangdong and the evolution of melting interfaces

Re-encoding of the geological and geochemical data concerning the Guidong Composite Granite Body(CGB) with the hypothesis of in-situ melting and crustal convection suggests that the Guidong CGB was formed by repeated crustal melting of this area in the Mesozoic.On that basis,this paper rebuilds the melting interface(MI) formed in different Yanshanian periods: the MI formed in the Early Jurassic totally tilts from south to north,which resulted in the early Yanshanian granite cropping out from inner facies to...