摘要
五龙矿床是中国辽东地区最大的石英脉型金矿床,赋存于中生代黑云母花岗岩中。金矿体多呈脉状产出,与中生代细粒闪长岩有成因联系。文章采用LA-ICP-MS锆石U-Pb定年方法,获得矿区内黑云母花岗岩、花岗斑岩、细粒闪长岩的结晶年龄分别为(155.4±0.9)Ma、(154.2±1.2)Ma、(123.1±0.9)Ma。文章选取金矿石中绢云母样品开展了Ar-Ar定年,获得Ar-Ar坪年龄为(122.8±0.8)Ma(MSWD=0.09)。金属硫化物的δ34S值介于+1.1‰^+2.4‰,平均值为+1.8‰,表明硫主要来自深源岩浆。黄铁矿中流体包裹体3He/4He比值为0.36~0.65Ra,平均值为0.50 Ra,表明地幔流体参与成矿作用的比例为3.9%~7.2%,地壳流体占主导地位。五龙金矿的成矿时代为早白垩世,形成于华北克拉通东部的构造体制转折和大规模岩石圈减薄背景。
The Wulong deposit is the largest quartz vein type gold deposit in eastern Liaoning Province. The orebodies are hosted in the Mesozoic biotite granite. The orebodies occur as veins, which have a genetic relation to the Mesozoic fine-grained diorite. The high precision LA-ICP-MS zircon U-Pb dating method wasadopted to measure the ages of the biotite granite, granite porphyry and fine-grained diorite in the Wulong deposit, which yielded （155.4±0.9） Ma, （154.2±1.2） Ma and （123.1±0.9） Ma, respectively. A sericite sample in gold ore was selected for the Ar-Ar dating method to determine the mineralization age of the Wulong gold deposit. An Ar-Ar plateau age defined by a sericite sample yielded an age of （122.8±0.8） Ma （MSWD=0.09）. The δ34S values of metallic sulfides range from ＋1.1‰ to ＋2.4‰, with an average of ＋1.8‰, suggesting that the sulfur came mainly from deep magma. 3He/4He ratios of fluid inclusions in pyrite range from 0.36 to 0.65 Ra with an average of 0.50 Ra. The mantle helium involved in the ore-forming fluid is 3.9% to 7.2%, suggesting the dominance of the earth＇s crust fluid. The ore-forming age of the Wulong gold deposit is early Cretaceous. The Wulong deposit was formed in a tectonic regime transformation and lithosphere thinning setting in eastern part of the North China Craton.
作者
刘军
王树岭
李铁刚
杨艳
刘福兴
李生辉
段超
LIU Jun;WANG ShuLing;LI TieGang;YANG Yan;LIU FuXing;LI ShengHui(MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;Department of Land and Resources of Inner Mongolia Autonomous Region,Hohhot 10020,Inner Mongolia,China;Development Research Center of Chinese Geological Survey,Beijing 100037,China;No.103 Geological Party of Non-ferrous Geological Bureau of Liaoning Province,Dandong 118008,Liaoning,China)
出处
《矿床地质》
CAS
CSCD
北大核心
2018年第4期712-729,共18页
Mineral Deposits
基金
国家重点研发计划项目(编号:2017YFC0601403)
国家自然科学基金项目(编号:41672066)
中国地质科学院基本科研业务费项目(编号:YYWF201512)联合资助
