河南省淅川县毛堂金矿区花岗斑岩锆石U-Pb年龄、Hf同位素特征及其地质意义  

Zircon U-Pb age and Hf isotopic characteristics of granite porphyry in the Maotang gold deposit,Xichuan county,Henan province and their geological significance

作　　者：蓝永强 曾威[2] 俞礽安 段明 LAN Yongqiang;ZENG Wei;YU Rengan;DUAN Ming(Sinosteel Group Tianjin Geological Academy Co. Ltd, Tianjin 300061, China;Tianjin Geological Survey Center, Tianjin 300170, China)

机构地区：[1]中钢集团天津地质研究院有限公司,天津300061 [2]中国地质调查局天津地质调查中心,天津300170

出　　处：《地质找矿论丛》2019年第2期232-241,共10页Contributions to Geology and Mineral Resources Research

基　　金：国家地质调查项目“中条-熊耳山成矿区地质矿产调查(编号:121201006000150003);中国地质调查局地质矿产调查评价专项“豫西成矿区资源远景调查评价”(编号:1212011120771);河南省地勘基金项目“河南省内乡县板厂一带多金属矿普查”(豫国土资发[2016]46)联合资助

摘　　要：毛堂金矿是位于河南省“毛堂—蒲塘铜金矿带”上的一个小型金矿,矿体主要产于老田岩体的Ⅲ号岩体中,成矿作用与隐爆角砾岩和花岗斑岩关系密切。通过对与成矿有关的隐爆角砾岩和花岗斑岩进行LA-ICP-MS锆石U-Pb同位素测年,获得其成岩年龄分别为143.0Ma±1.2Ma和141.4Ma±1.5Ma,代表矿床的形成时代;对花岗斑岩进行Hf同位素测试,其εHf(t)值分布范围为-3.4~4.2,平均为1.6,显示其源区为镁铁质新生地壳。毛堂金矿形成于早白垩世,受花岗斑岩、隐爆角砾岩及其构造-裂隙控制,矿床类型属于隐爆角砾岩型金矿。Maotang gold deposit is a small gold deposit located in the copper-gold belt of Maotang-Putang,Henan province.The ore body mainly occurred in the No.3 rock mass of the Laotian intrusion.The mineralization is closely related to cryptoexplosive breccia and granite porphyry.The LA-ICP-MS zircon U-Pb isotopic dating of the cryptoexplosive breccia and granite porphyry reveals that their diagenetic ages are 143.0 Ma±1.2 Ma and 141.4 Ma±1.5 Ma,respectively,representing the age of the deposit formation;the Hf isotopic test of granite porphyry shows that the distribution range of the values is-3.4 to+4.2,with an average of 1.6.It shows that the magma source area is the newborn mafic crust.The Matang gold deposit was formed in the early Cretaceous,controlled by granite porphyry,cryptoexplosive breccia,structures and fractures at all levels,and belongs to the cryptoexplosion breccia type.

关 键 词：LA-ICP-MS锆石U-PB测年 HF同位素 早白垩世 隐爆角砾岩型金矿床 河南省 

分 类 号：P597.1[天文地球—地球化学]