中文摘要:首次对延边小西南岔富金铜矿床矿田内产出的燕山晚期花岗杂岩进行了系统的锆石SHRIMP U-Pb年龄测定,获得中细粒黑云母二长花岗岩、中细粒黑云母花岗闪长岩和似斑状角闪花岗闪长岩的3组锆石谐和年龄数据,分别为98.4～109.0 Ma[加权平均值为(104.6±2.5)Ma,n=10,MSWD=0.71,置信度0.70]、98.3-108.3Ma[加权平均值为(106.7±1.6)Ma,n=12]和104.4～118.8 Ma(加权平均值为(111.7±2.8)Ma,n=12],指示它们的岩浆侵位时限在112-104 Ma之间,相对侵位时序为似斑状角闪花岗闪长岩、中细粒黑云母花岗闪长岩到中细粒黑云母二长花岗岩;考虑到它们在成矿元素和地质上与矿化的密切程度以及控(容)矿断裂的张扭性特征,进而确定大规模的金铜矿化应发生在似斑状角闪花岗闪长岩、中细粒黑云母花岗闪长岩、中细粒黑云母二长花岗岩形成之后,闪长玢岩之前,或在104.6～102.1 Ma之间,成矿环境应处于早白垩世晚期伊泽奈崎板块向古亚洲大陆边缘俯冲消亡、中国东部大陆边缘燕山造山期末的走滑、伸展构造转换过程.
Abstract:The SHRIMP U_Pb dating of zircons from the granitic complex in the Xiaoxinancha gold_rich copper orefield was conducted for the first time and, as a result, three concordant ages of zircons were obtained from medium_fine grained biotite monzonitic granite，medium_fine grained biotite granodiorite and porphyraceous hornblende granodiorite respectively, i.e., 98.4～109.0 Ma（weighted average value being(104.6±2.5) Ma，Nequal to 10, MSWD equal to 0.71, confidence level being 0.70），98.3～108.3 Ma（weighted average value 106.7± 1.6 Ma，n=12）and 104.4～118.8 Ma（weighted average value 111.7±2.8 Ma，n=12），suggesting that magmatic emplacement took place in 112～104 Ma in order of porphyraceous hornblende granodiorite，medium_fine grained biotite granodiorite and medium_fine grained biotite monzonitic granite Taking into account their relationships with mineralization in ore_forming elements and geological characteristics and the extensional_torsional features of the ore_controlling fractures, the authors hold that large_scale gold_copper mineralization must have occurred after the formation of porphyraceous hornblende granodiorite，medium_fine grained biotite granodiorite and medium_fine grained biotite monzonitic granite but before the emplacement of the associated dioritic porphyrite, i.e., between 1046 and 1021 Ma, and the metallogenic environment was the subduction and extinction of Izanaqi plate towards the ancient Asian continent in late Early Cretaceous and the conversion process of slip or extension structures in eastern China continental margin during the Late Yanshanian orogenic movement.
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基金项目:国家自然科学基金（40472050；40772052）;南京大学内生金属成矿机制国家重点实验室基金（2006_2005，2006_2008） , 南京大学内生金属成矿机制国家重点实验室基金
引用文本：
孙景贵,陈 雷,赵俊康,门兰静,逄 伟,陈 东,梁树能.2008.延边小西南岔富金铜矿田燕山晚期花岗杂岩的锆石SHRIMP U-Pb年龄及其地质意义[J].矿床地质,27(3):0SUN JingGui,CHEN Lei,ZHAO JunKang,MEN LanJing,PANG Wei,CHEN Dong, LIANG ShuNeng.2008.SHRIMP U-Pb dating of zircons from Late Yanshanian granitic complex in Xiaoxinancha gold-rich copper orefield of Yanbian and its geological implications[J].Mineral Deposits27(3):0
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