江西相山矿田主要铀矿化类型及其地球化学特征对比研究

江西相山矿田发现近30个铀矿床，矿化与浅成超浅成侵入岩(次火山岩)关系密切，不管是划归火山岩型还是斑岩型矿床类型，均属于热液型矿床。从热液矿床的成矿构造特点分析，相山矿田铀矿化主要有隐爆碎屑岩型和蚀变岩型两大类，后者主要有水云母化蚀变岩型和钠长石化蚀变岩型。通过收集资料，结合笔者完成的有关课题成果数据，对各铀矿化类型进行了地球化学的对比研究，结果表明：隐爆碎屑岩型矿石品位较高，U含量大多大于1%，SiO₂、Na₂O含量较低，P₂O₅含量较高，K₂O/Na₂O比值平均11.51，主要伴生元素有Hf、Sb、Cu、Pb、Zn、Zr等；水云母化蚀变岩型矿化的K₂O/Na₂O比值平均4.83，伴生元素有W、Pb、Mo、Th、Sb等；钠长石化蚀变岩型矿化的K₂O/Na₂O比值平均0.19，U与CaO、P₂O₅关系密切，伴生元素有Sr、Zr、Hf、Sc、W等。从钠长石化蚀变岩型，到水云母化蚀变岩型，到隐爆碎屑岩型，即随矿化岩石U品位的增高，稀土配分曲线呈现出从右倾向左倾有规律的变化。

Main Uranium Mineralization Types and Their Comparison of Geochemical Characteristics in Xiangshan Orefield,Jiangxi

Nearly 30 uranium deposits found in Xiangshan orefield of Jiangxi Province, whose uranium mineralization are closely related to hypabyssal or super hypabyssal intrusive rock (subvolcanic rock). Whether porphyry or volcanic rock type is hydrothermal uranium deposits. Analyzing from the metallogenic tectonic characteristics of the hydrothermal deposits in the orefield, there are two kinds of uranium mineralization, namely, cryptoexplosion clastic rock type and alteration rock type, the latter mainly includes hydromica altered rock type and albitization altered rock type. In this paper, by collecting data, combining with the data of relevant topics, a comparative study of geochemical characteristics of various uranium mineralization was carried out. Results show that, the ore grade of cryptoexplosion clastic rock type is higher, and mostly content of U is more than 1%. There is lower SiO₂ and Na₂O and higher P₂O₅ , and the ratio of K₂O and Na₂O is 11.51 on average, and the main associated elements are Hf, Sb, Cu, Pb, Zn, Zr, etc.; K₂O/Na₂O of hydromica altered rock type is 4.83 on average, and associated elements are W, Pb, Mo, Th, Sb, etc.; K₂O/Na₂O of albitization altered rock type is 0.19 on average, U has a close relationship with CaO and P₂O₅, and associated elements are Sr, Zr and Hf, Sc, W, etc. From the albitization altered rock type, to hydromica altered rock type, to the cryptoexplosion clastic rock type, with the increasing of U grade, REE distribution curve appears a regular change from right to left lean.