东川桃园式铜矿Ar-Ar同位素年龄及意义  

THE Ar-Ar ISOTOPIC AGE IN DONGCHUAN TAOYUAN TYPE COPPER DEPOSIT,YUNNAN PROVINCE AND ITS SIGNIFICANCE

作　　者：叶霖[1] 刘玉平[1] 李朝阳[1] 刘家军[1] 

机构地区：[1]中国科学院地球化学研究所矿床开放实验室

出　　处：《矿物岩石》2004年第2期57-60,共4页Mineralogy and Petrology

基　　金：中国科学院知识创新工程项目(编号:KZCX2-101);中国科学院矿床地球化学开放实验室基金

摘　　要：　通过对东川桃园铜矿与铜矿共生石英的40Ar/39Ar同位素年龄的测定,得到马鞍形年龄谱,其坪年龄为768.43Ma±0.58Ma,等时线年龄为770.00Ma±5.44Ma。该矿床后期改造作用明显,并非同生沉积或成岩作用早期成矿,而与晋宁期Rodina大陆裂解有关。东川铜矿的形成可能是在Rodinia大陆裂解时,从深部带来大量成矿物质改造成岩时期初始的矿化,形成矿床的叠加富集和最终定位,因此,晋宁-澄江期是东川铜矿的主成矿期。The selliform age spectrum was revealed by determining ()^(40)Ar/()^(39)Ar isotopic age in Dongchuan Taoyuan type copper deposit. The result shows that the minerogenetic age is Jinning period (784 Ma).It is obvious that the deposit was reformed by later hydrothermal activity.In fact,the deposit did not belong to idiogenous sedimentation or formed in early stage of diagenesis and the mineralization was related with the Jinningian break-up of Rodinia. It was indicated that Jinningian-Chunjiangian was the main mineralization stage in Dongchuan copper deposit, the abundant minerogenetic materials was brought up from the depth,which reformed original mineralization during the Jinningian-chunjiangian break-up of Rodinia,resulting in the ultimate emplacement of Dongchuan copper deposit.

关 键 词：^40AR/^39AR同位素年龄 铜矿 矿床改造 沉积 成岩作用 

分 类 号：P597.3[天文地球—地球化学] P571[天文地球—地质学]