粤西阳春盆地锡山钨锡矿成矿岩体微量元素地球化学特征

Trace Elements Geochemical Characteristics in Ore-forming Rocks of Xishan Tungsten-tin Deposit,Yangchun Basin,Guangdong Province

锡山钨锡矿床是粤西阳春盆地内具有代表性意义的钨锡典型矿床,其成矿与岩体直接相关。本文采用等离子质谱仪(ICP-MS)方法对锡山岩体的主体岩性进行了微量与稀土元素分析,研究结果表明:锡山岩体的微量元素以Bi、Mo、W的显著或明显富集为特征,但成矿元素Sn的富集不明显。在岩体微量元素原始地幔标准化蛛网图上,各样品均具有Rb、Th、U等元素的明显富集,而Ba、Sr、P、Ti等元素显著亏损的地球化学特征。岩体的稀土元素球粒陨石标准化配分模式均表现为较平坦型的雁式曲线,轻重稀土元素分馏不明显,具有显著Eu负异常。微量元素和稀土元素的地球化学特征均表明锡山岩体为较典型的A型花岗岩。

Xishan tungsten-tin deposit＇s mineralization is related to rock mass, it is a typical deposit in Yangchun ba- sin. The article uses ICP-MS to analysis trace and rare earth elements of Xishan rock. The result shows that Bi, Mo. W significantly enriched, but Sn is not obvious. On the basis of the primitive mantle normalization map of trace ele- ments in rock mass, all kinds of products have obvious enrichment of Rb, Th, U, while the geochemical character- istics of Ba, Sr, P, Ti and other elements are obviously deficient. The chondrite normalized patterns of rare earth elements in the pluton shows fiat goose shape curves, and the fractionation of LREE and HREE is not obvious, with significant Eu negative anomalies. All the geochemical characteristics indicate Xishan pluton is a typical A type granite.