摘要
本文按摩天岭含铀花岗岩体的花岗岩、弱蚀变花岗岩、钾交代花岗岩和硅质交代花岗岩4种岩石类型,探讨了岩石中的常量元素、大离子亲石元素(LILE)、高场强元素(HFSE)和稀土元素(REE)含量特征及相互间的关系。其中含铀钾交代花岗岩表现为强钾长石化、强绿泥石化和弱赤铁矿化,U含量与次生黑云母关系密切;含铀硅质交代花岗岩的U含量与微晶石英伴生的铁质有关。通过剖析不同类型岩石的地球化学特征,指出成矿流体的元素主要来自花岗岩,产铀岩石具明显的LLH特征;伴随铀矿化的增强,K/Ba、Rb/Sr值降低,而Ba/Rb值增高;含铀钾交代花岗岩和硅质交代花岗岩的HFSE和REE含量呈共轭消长和重稀土(HREE)相对富集的特征。提出伴随断裂开启多期成矿流体的叠加更有利于铀的富集,LLH特征,以及K/Ba、Rb/Sr值降低与Ba/Rb值增高可作为含铀花岗岩体的地球化学判别依据。
This paper discusses the content and interrelationship of major element,large-ion lithophile elements（LILE）,high field strength elements（HFSE） and rare-earth element（REE） in four rock types such as granite,poor-alteration granite,potash and kiesel metasomatic granite of uranium-bearing granite mass,Motianling area.The uraniferou potash metasomatic granite is shown intensive K-feldspar alteration,chloritization and poor hematitization,and the uranium content is related with secondary blotite intently.The uranium content in uraniferou kiesel metasomatic granite is relevanted to ferruginous matter which was associated with microcrystalline quartz.Dissect the geochemical behavior in different rock types,judge that the element which included in mineralizing fluid have been released from granite,uraniferou rocks were shown low K/Rb（L）,low Ba/Rb（L） and high Rb/Sr（H） apparently,and the reinforce of uranium mineralization was accompanied with the decrease of K/Ba,Rb/Sr and increase of Ba/Rb value.The content of HFSE and REE were shown conjugate decrease and increase and HREE enrichment relatively in uraniferou potash and kiesel metasomatic granite.Submit that the superimposed of multiple phase mineralizing fluid accompanied with fault unsealing was favour of uranium enrichment,the characteristic of LLH and the decrease of K/Ba,Rb/Sr with increase of Ba/Rb could be acted as the geochemistry distinguish foundation of uranium-bearing granite mass.
出处
《矿物岩石地球化学通报》
CAS
CSCD
北大核心
2011年第4期415-422,共8页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
全国铀矿资源调查评价项目资助(1212010913008)
