摘要
四川会理小青山铜(金)矿区的钠长石英板岩主要由钠长石及石英组成。钠长石英板岩的化学成分中富SiO_2、Al_2O_3及Na_2O,贫K_2O、FeO及MgO;稀土元素特征为:ΣREE=30.13～42.11,ΣCe/ΣY=1.80～1.98,δEu=0.23～0.34,δCe=0.48～0.59。钠长石英板岩是由绢云母千枚岩及(碳质)板岩等变泥质岩经钠交代作用形成的。部分钠化的岩石中常有原岩的结构、构造及矿物的残留。区内的铜(金)矿床与钠长石英板岩的形成作用密切相关。
Na-metasomatic rocks in Xiaoqingshan, Huili County, Sichuan Province, have been recognized as adinoles. The rocks are distributed along major faults or adjacent to small mafic intrusions. The protolith of adinoles is metapelites, such as seriscite phyllite and carbonaceous slate. The adinoles consist of albite. quartz and minor tourmaline and rutile. They are characterized by various kinds of metsomatic textures. Most of the rocks were superposed by late alteration marked by the assemblage of carbonate-chlorite-pyrite-auriferous chalcopyrite. Mass balance calculation indicates that K2O, MgO, Fe2O, FeO, Rb, Ba and REE were removed from the metapelites, while Na2O and SiO2 were added. In contrast, A12O3 was almost immobile. It is important that Cu (Au) mineralization occurred during the metasomatisms. The authors suggest that alkaline fluids from the deep levels were responsible for the Na and late-stage metasomatism and mineralization during the extension of the crust.
出处
《地质论评》
CAS
CSCD
北大核心
1999年第3期323-327,共5页
Geological Review
关键词
钠长石英板岩
钠交代作用
铜矿床
金矿床
adinole
Na-metasomatism
copper (gold) deposit
Huili County, Sichuan Province
