摘要
杜荒岭金矿床是中国东北部吉林省延吉地区典型的浅成热液高硫化型金矿床之一,矿区内发育大量早白垩世火成岩。为了更深入地认识杜荒岭金矿床的岩浆作用、岩浆起源及成矿条件,本文在已有研究基础上对矿区内含矿的石英闪长岩、花岗闪长岩和花岗闪长斑岩中的锆石进行了微量元素测试。结果显示,绝大多数锆石Th/U值>0.1,锆石的球粒陨石标准化REE配分曲线呈左倾配分型式,强烈富集重稀土元素、亏损轻稀土元素,并存在不同程度的Ce正异常与Eu负异常;研究对象为典型岩浆锆石,结晶温度主要介于700~900℃之间。研究认为含矿岩石起源于下地壳部分熔融,形成于板块俯冲的弧构造环境。此外,成矿岩体花岗闪长斑岩锆石相比成矿前岩石具有较高的Ce^(4+)/Ce^(3+)值和较低的结晶温度,指示花岗闪长斑岩岩浆具有高氧逸度和含水量,即高成矿潜力。而岩浆氧逸度和含水量的差异可能是石英闪长岩和花岗闪长岩未成矿的原因。
Duhuangling gold deposit is one of the high-sulphidation epithermal gold deposits in Yanji area,northeast China,where a large number of Early Cretaceous igneous rocks are developed.In order to understand the magmatism,magma sources and ore-forming condition of Duhuangling gold deposit,integrated with the results of previous research,we conducted trace element analyses of zircons from the ore-bearing quartz diorite,granodiorite and granodiorite porphyry in ore district.The majority of zircons possess high Th/U values(>0.1),and their chondrite-normalized REE patterns of all zircons are characterized by HREE enrichment relative to LREE and MREE with distinctive positive Ce and negative Eu anomalies,which are typical of magmatic zircons.All the zircons yield different Ti-in-zircon temperatures,with most zircon crystals between 700 to 900℃.Zircon trace elements provide that the ore-bearing rocks were derived from the partial melting of the lower crustal materials and formed in the arc environment related to the plate subduction.In addition,the zircon grains have higher Ce^(4+)/Ce^(3+)values and lower temperature in the melt of ore-forming granodiorite porphyry than pre-ore rocks,indicating that granodiorite porphyry has high oxygen fugacity,water contents and ore-forming potential.Therefore,the difference in magmatic oxygen fugacity and water contents may be the reasons why the quartz diorite and granodiorite are not mineralized.
作者
柴鹏
孙景贵
袁玲玲
门兰静
Chai Peng;Sun Jinggui;Yuan Lingling;Men Lanjing(Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China;Laboratory of Deep Earth Sciences and Technology,Ministry of Natural Resources,Beijing 100037,China;College of Earth Sciences,Jilin University,Changchun 130061,China;Key Laboratory of Mineral Resources Evaluation in Northeast Asia,Ministry of Natural Resources,Changchun 130061,China;School of Prospecting and Surveying Engineering,Changchun Institute of Technology,Changchun 130021,China)
出处
《吉林大学学报(地球科学版)》
CAS
CSCD
北大核心
2023年第3期767-784,共18页
Journal of Jilin University:Earth Science Edition
基金
国家自然科学基金项目(41973045,41602084)
国家重点研发计划项目(2018YFE0204202)
中国地质调查局项目(DD20230213,DD20221647,DD20190685)
中国地质科学院地质研究所基本科研业务费项目(J1905)
自然资源部东北亚矿产资源评价重点实验室开放课题基金项目(DBY-KF-18-02)
关键词
吉林延吉
浅成热液高硫化型金矿床
杜荒岭金矿床
锆石
微量元素地球化学
Yanji area
Jilin Province
high-sulfidation epithermal gold deposit
Duhuangling gold deposit
zircon
trace element geochemistry