新疆阿尔泰山南缘乔夏哈拉式铁铜矿床稀土元素地球化学特征及其地质意义  

REE geochemistry of Qiaoxiahala type Fe-Cu deposits in southern margin of Altay Mountains, Xinjiang, and its geological implications

作　　者：闫升好[1] 张招崇[2] 王义天[1] 陈柏林[3] 周刚 何立新 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]中国地质科学院地质研究所,北京100037 [3]中国地质科学院地质力学研究所,北京100081 [4]新疆地矿局第四地质队,新疆阿尔泰836500

出　　处：《矿床地质》2005年第1期25-33,共9页Mineral Deposits

基　　金：国家重点基础研究973项目(2001CB409807);国家科技攻关305项目(2001BA609A_07_02)资助

摘　　要：通过野外地质调查和系统的稀土元素地球化学研究,探讨了阿尔泰山南缘乔夏哈拉式铁铜矿床中磁铁矿矿体和块状富铜矿体的成因关系及找矿意义。研究表明,乔夏哈拉铁铜矿床中铁矿体和富铜矿体的稀土元素组成及配分模式迥然不同。前者具有低∑REE、富轻稀土元素及正铕异常等特点,指示火山成因性质;后者异常富集轻稀土元素、配分曲线向右倾陡,其成因可能与造山期中基性浅成岩浆作用有关。据此认为,铁矿体和铜矿体并非“同生”成因关系,很可能是两期成矿作用在空间上的“同位叠生”关系。Based on detailed geological field survey and systematical REE geochemical study, the authors have discussed the genetic relationship between the magnetite orebodies and massive copper_rich orebodies as well as its significance in the prospecting for Qiaoxiahala type Fe_Cu deposits in the southern margin of Altay Mountains, Xinjiang. It is concluded that the magnetite ore is distinctively different from the copper_rich massive ore in REE composition and distribution model. The former has ∑REE_poor, LREE_rich, and positive Eu anomaly, indicating that the ore_forming process was genetically related to submarine volcanism. The latter has unconventionally rich LREE with steep right_dipping REE distribution curves, suggesting that its generation might have been linked to shallow intermediate_basic orogenic magmatism. Therefore, the coexistence of the magnetite ore and the massive copper_rich ore resulted probably from the spatial superimposition of two stages of ore_forming processes related to different tectono_magmatic activities instead of from syngenetic relationship.

关 键 词：稀土元素地球化学 铁铜矿床 块状硫化物矿床 乔夏哈拉 阿尔泰山 

分 类 号：P618.41[天文地球—矿床学] P595[天文地球—地质学]