作　　者： ; ;

机构地区： 中国地质大学地球科学学院

出　　处： 《矿物学报》 2003年第1期37-44,共8页

摘　　要： 应用改善了的质量平衡方程研究冬瓜山层控夕卡岩型铜矿床成矿系统的元素活动性及质量迁移 ,结果表明 :系统中Zr,Hf,Y和Nb为不活动元素 ,其余均为活动元素。主量元素中仅CaO为迁出组分 ,其质量迁移量为 84% ,其余均为带入组分 ,带入量最大的SiO2 的质量迁移量高达 2 3 84% ;稀土元素均为带入组分 ,其中 ,中稀土较轻稀土和重稀土的活动性更强 ;其它微量元素中 ,带入序列由强到弱为 :Cr→Ta→Sn→Th,迁出序列由强至弱依次为 :U→Sb→Ni→Sr→Ba→Rb→Co→W ;成矿元素Cu和Ag为带入组分 ,其中Cu的带入量最大 ,质量迁移量高达 1 2 0 0 %。本文还得出两点具普适性认识 :①稀土元素较其它微量元素对体系条件的变化更为敏感 ,且往往表现出明显的规律性变化 ,能更好地示踪地质地球化学过程。②不同元素在不同体系中的行为特征差异极大 ,仅凭经验判定某一元素为不活动元素往往不可靠。因此 ,在开展质量平衡研究时 ,首先采用适当方法确认体系的不活动元素是一项不可或缺的前提工作。 The element mobility and mass transfer of ore forming system of the Dongguashan strata bound skarn copper deposit have been studied by a newly improve d mass balance method. It is demonstrated that Zr, Hf, Y and Nb show immobility and the other elements show mobile behavior during the formation of skarns. Amon g the major elements, Ca removed from the system comes up to 84%, while the othe rs were incorporated into the skarns. All the rare earth elements were introduce d into the system, among which MREE were more mobile than LREE and HREE. For oth er trace elements, the input amounts decrease gradually in the order of Cr→Ta →Sn→Th, and the output in the order of U→Sb→Ni→Sr→Ba→Rb→Co→W. Major ore forming elements such as Cu and Ag were incorporated into the skarns, of which Cu put into the skarn comes up to 1 200%. Two general conclusions may be draw n as follows. Firstly, the REE are more se nsitive to the variation of the formation condition of rock systems than other t race elements and generally show evident regularities. Consequently, the REE cou ld be more useful for tracing the evolution history of the rock system than othe r trace elements. Secondly, element mobility is very different in various geoche mical processes, and it is difficult to ascertain the immobile elements only by experiences. One has to find immobile elements with adequate methods before stud ying mass transfer of a geological system.

关 键 词： 层控夕卡岩型矿床 成矿系统 元素活动性 稀土元素 微量元素

领　　域： [天文地球] [天文地球] [天文地球] [天文地球]