摘要
笔者选取了华南印支期大部分花岗岩体,通过比较不同类型花岗岩的元素地球化学特征来确定产铀花岗岩的指示性特征.对比结果显示,花岗岩的源区和成因类型不同,是导致其产铀能力不同的主要因素.华南印支期产铀花岗岩的主要特征是：成岩年龄为219～250Ma,成岩温度和氧逸度低,属于S型花岗岩,其经历同碰撞的构造背景,主要分布在华夏地块内.产铀花岗岩以二云母花岗岩和黑云母花岗岩为主,蚀变作用强,副矿物组合复杂.花岗岩中结晶分异作用强,SiO2、K2O和P2O5含量高,而Al2O3、TiO2、FeO、MgO和CaO含量低,Th/U值低.这些指示性标志是指导铀矿勘查的重要线索.
This article studied most Indosinian plutons in South China, and work out the indicative char- acter of uranium - deposit - bearing granites （UY）G）. The source region and the genetic type of granite are the principal cause of uranium - bearing. The main characteristic of UDG in South China is as follows. The forming ages is Indosinian from 219 to 250Ma and located in the Cathaysian plate. It had lower zircon saturation tempture and lower oxygen fugacity. It had the same character with S type granite. The biotite of UDG has strong degree of alteration, more accessory mineral inclusions. Compared with non- uranium-deposit- bearing granites （NUI~）, UDG are characterized by relative enrichment of SiO2, K20, P2Os, Pb, U, Th, Rb and LREE, but depletion of A1203, TiO2, FeO, MgO, CaO, Sr, Ba and Eu, indicating that UDG had undergone stronger fractional crystallization. This indicative charac- ters may help us in uranium exploration.
出处
《铀矿地质》
CAS
CSCD
2014年第3期141-148,154,共9页
Uranium Geology
关键词
元素地球化学特征
印支期花岗岩
铀成矿
华南
geochemical characteristic
Indosinian granite
uranium- metallization
South China
