摘要
对都庞岭复式岩体各期次花岗岩以及含矿云英岩化学成分、挥发分元素及成矿元素的统计分析表明:本区锡钨矿化与花岗岩关系密切,矿化是花岗岩演化到一定阶段的产物。自γ_3→γ_5~1→γ_5^(2a)→γ_5^(2b),随着岩浆成分有规律地演化,Sn,W逐渐富集。其中,挥发组分F,Li是Sn,W富集的主要控制因素。当已富集成矿元素Sn,W和挥发组分F,Li,CO_2的含矿岩浆发生分异时,挥发组分F,Li对Sn,W的进一步富集成矿起主导控制作用,CO_2则促进含矿岩浆发生不混溶,从而促使Sn,W富集于富F,Li的液体相中。相对来说,在岩浆演化和合矿岩浆的分异过程中,F,Li对Sn的富集成矿比对W的富集成矿所起作用更大。
The statistics of the chemical composition, volatile and ore-formingelements of the granites of Dupangling composite granite body and ore-bearing greisens in ore-bearing granite reveals that there are close geneticrelations between the Sn and W mineralization and the granites and that theSn and W mineralization is produced as a result of the evolution of graniticmagmas. From γ_3→γ_5~1→γ_5^(2a)→γ_5^(2b), with the regular compositional evolu-tion of granitic magma, Sn and W are gradually enriched. As to the Snand W enrichment, volatile components F and Li play important rolesbut volatile constituent CO_2 does not. During the differentiation of Sn-and W-enriched and F- and Li-enriched ore-bearing magma, F and Liplay a controlling role in further enriching ore-bearing elements Sn andW, while CO_2 promotes the immiscibility of ore-bearing magma and theenrichment of Sn and W into F- and Li-rich melt phase. On the whole,in the process of magma evolution and ore-bearing magma differentiation,F and Li play more important role in enriching Sn than in enriching W.
关键词
岩浆
演化
含矿
锡
钨
分异
magma evolution
magma differentiation
Sn
W
enrichment factor
Guangxi
Dupangling
