云南易门狮子山铜矿基性侵入岩地球化学特征及其地质意义  

GEOCHEMICAL CHARACTERISTICS OF BASIC INTRUSIVE ROCKS IN SHIZISHAN COPPER DEPOSIT,YIMEN,YUNNAN,AND ITS GEOLOGICAL SIGNIFICANCE

作　　者：杨勇[1] 韩润生[1] 王雷[1] 李波[1] 胡一多[1] 

机构地区：[1]有色金属矿产地调中心西南地质调查所,昆明理工大学

出　　处：《矿物岩石》2010年第1期69-74,共6页Mineralogy and Petrology

基　　金：国家科技支撑项目(2006BAB01B09);国土资源部危机矿山专项(20089943;200653057)

摘　　要：针对云南易门狮子山铜矿区基性侵入岩体(以矿区1237m中段层状辉长岩为例)的岩石学和地球化学特征分析,结果表明:SiO2,Na2O和K2O的平均质量分数分别为47.06%,3.91%,2.17%,σ(里特曼指数)平均为9.9;微量元素表现为大离子亲石元素K,Rb,Th明显富集,Sr,Ta,Nb,Yb,Cr,Y等元素亏损,显示了大陆裂谷玄武岩的特征;稀土元素总量为178.60×10-6～404.50×10-6,Eu负异常不明显(0.73～0.97),轻稀土元素富集(LREE/HREE=7.05～16.59,(La/Yb)N=6.56～36.94);研究还认为狮子山基性侵入岩是在大陆初始裂谷背景下形成的,属于深源玄武质岩浆演化形成,可能有壳源物质的混入。Shizishan Copper deposit is a typical deposit occurred in the Kunyang rift of the Proterozoic Yangtze continent. In the ore district,layered basic intrusive rock bodies of gabbro intruded into the surrounding country rock. It was revealed that the average concentration of SiO2, Na2O and K2O of the intrusive rocks are 47.06%,3.91%,2. 17%,and the average eoneentration of σ is 9.9. Trace elements of K,Rb,Th were enriched and Sr,Nb,Yb,Cr,Y were depleted,similar to the intra-eontinental rift basahs. Total REE ranges from 178.60 to 404.50 × 10^- 6 with no pronounced Eu negative anomaly（δEu=0.73-0.97） and with I.REE enriehment（LREE/ HREE=7.05-16.59, （La/Yb）x =6.56~36.94）. Based on the study of geology, petrology and petrogeochemistry,it was considered that the basic intrusive rock bodies formed in initial continental rift environment and resulted from the deep source of formation of basaltic magma, mixed with crustal material.

关 键 词：狮子山铜矿 辉长岩 岩石地球化学 大陆初始裂谷 

分 类 号：P588.124[天文地球—岩石学] P595[天文地球—地质学]