云南个旧塘子凹锡多金属矿床夕卡岩地质地球化学特征  

Geological and Geochemical Characteristics of Skarns from the Tangziwa Tin——Polymetallic Deposit,Gejiu District,Yunnan Province,China

作　　者：贾润幸[1] 方维萱[1] 胡瑞忠[1] 马振飞 

机构地区：[1]中国科学院地球化学研究所矿床地球化学重点研究实验室 [2]云南锡业股份有限公司采选分公司,云南个旧661000

出　　处：《地质论评》2007年第2期281-288,I0012,共9页Geological Review

基　　金：国家"十五"科技攻关项目(编号2004BA615A-03);国家重大基础研究规划项目(编号2001CB409805)的成果

摘　　要：从地质产状、矿物组合和岩石化学成分等方面探讨了个旧塘子凹接触带不同类型夕卡岩的特征。该夕卡岩带从内侧到外侧常具有辉石夕卡岩带和石榴子石夕卡岩带交替出现的现象,其岩石化学成分也相应地发生韵律变化,表现为在辉石夕卡岩带中SiO_2和MgO含量较高,而在石榴子石夕卡岩带中CaO、TFe和Al_2O_3含量较高。认为夕卡岩带中的韵律变化一方面与被交代围岩中存在灰质白云岩和大理岩的互层带有关,另一方面与岩浆期后热液的渗滤交代作用有关。围岩中的灰质白云岩层被交代后形成辉石带,大理岩层被交代后形成石榴子石带。There are rhythmic skarn zoning, mainly magnesian skarns and calcic skarns, in contract metasomtites between Yanshanian granites and Triassic carbonate rocks in the Tangziwa deposit, Gejiu. The magnesian skarns and calcic skarns were located in the contract by turns form inner side to outer side accompanying the variety of mineral association and chemical composition. The mineral association of magnesian skarns are mainly diopside with relatively high content of SiO2 and MgO, and that of calcic skarns are mainly garnets with relatively high content of CaO, TFe and Al2O3. The writers think that this occurrence of the rhythmic skarn zonation in contract are mainly related to the two factors, one is to the rhythmic strata of calcic dolomite and marble in wallrocks, and the other to the infiltration metasomatism of post-magmatic hydrothermalism.

关 键 词：夕卡岩 锡多金属矿 渗滤交代作用 云南个旧 

分 类 号：P618.44[天文地球—矿床学]