Age and fluid source constraints of the Haoyaoerhudong orogenic gold deposit,North China:Evidence from geochronology and noble gas isotopes  

作　　者：Chenglong Fan Jingwen Mao Huishou Ye Yitian Wang Junchen Liu Wei Jian Xuyang Meng Wenhao Tang Weiwei Chao Peng Wang 

机构地区：[1]School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China [2]MNR Key Laboratory for Exploration Theory&Technology of Critical Mineral Resources,China University of Geosciences,Beijing 100083,China [3]Ministry of Natural Resources(MNR)Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China [4]Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources by the Province and Ministry,Guilin University of Technology,Guilin 541004,China [5]State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,Jiangxi,China [6]School of Earth Sciences and Spatial Information Engineering,Hunan University of Science and Technology,Xiangtan 411201,China

出　　处：《Geoscience Frontiers》2024年第4期176-195,共20页地学前缘（英文版）

基　　金：financial support from the Academic-Industry Cooperation Project(grant HE1913);National Natural Science Foundation of China(41972094).

摘　　要：The Haoyaoerhudong gold deposit,located in the northwestern part of the North China craton(NCC),has produced over 120 metric tonnes(t)of gold since 2007.It has a total reserve of>240 t at average gold grade of 0.62 g/t,making it one of the largest open pit gold mines in China.The steeply dipping,large-tonnage,low-grade,vein-or veinlet-type gold orebodies are hosted in strongly-deformed Mesoproterozoic carbonaceous schist of the Bayan Obo Group.The laminated/boudinaged veins/veinlets in the sinistral ductile-brittle shear zones are dominated by quartz,biotite,gold-bearing löllingite,pyr-rhotite,(arseno)pyrite,with minor native gold,titanite and xenotime.In this paper,we present new in situ U-Pb geochronological data on magmatic zircon from the preore dikes,on metamorphic and hydrothermal xenotime,and on hydrothermal titanite from the hydrothermally altered carbonaceous schist and auriferous quartzsulfides veins/veinlets,as well as He-Ar isotopic analysis on gold-bearing(arseno)pyrite in the syn-ore stage.The metamorphic xenotime U-Pb age of 426±6.0 Ma(2σ)records a regional metamorphic event,possibly related to the accretion of the Bainaimiao arc onto the NCC.Two pre-ore andesitic dikes yielded similar emplacement ages at~278 Ma constrained by laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)U-Pb zircon data.Hydrothermal xenotime grains from the altered carbonaceous schist and auriferous quartz-sulfides veins yielded U-Pb ages of 256.0±4.1 Ma(2σ)and 254.4±2.1 Ma(2σ),respectively,overlapping with that of the hydrothermal titanite at 255.4±0.8 Ma(2σ)from the laminated quartz-sulfides veinlets.This indicates that the gold mineralization occurred at ca.255 Ma.The~255 Ma gold mineralization age is much younger than the previously reported Early-Middle Permian regional magmatic activity(ca.291 Ma to 268 Ma),and may be associated with the regional sinistral strike-slip event in the late orogenic cycle related to the collision between the Siberian craton and the NCC.The 3He/4He(R/Ra)and 40Ar/3

关 键 词：XENOTIME TITANITE In situ U-Pb dating Noble gas Orogenic gold deposit North China Craton 

分 类 号：P618.51[天文地球—矿床学]