永平铜矿十字头-火烧岗岩体地球化学特征及构造背景  

Geochemical characteristics and tectonic setting of the ShizitouHuoshaogang rock mass in the Yongping copper mine

作　　者：许红光 王健 郑文斌 王新旭 李悝 钟锐 方行 谢云辉 Xu Hongguang;Wang Jian;Zheng Wenbin;Wang Xinxu;Li Kui;Zhong Rui;Fang Hang;Xie Yunhui(The 8th Geological Brigade of Jiangxi Bureau of Geology,Shangrao,Jiangxi,334000,China)

机构地区：[1]江西省地质局第八地质大队,江西上饶334000

出　　处：《化工矿产地质》2024年第4期289-300,共12页Geology of Chemical Minerals

摘　　要：永平铜矿位于北武夷成矿带北缘,近年来的勘查工作,在矿区铜矿深部新发现了中型以上规模异体共生的钼矿,与岩体成矿关系密切。本文对永平铜矿十字头-火烧岗岩体开展了岩石学和岩石地球化学等方面的分析研究,结果显示:永平矿区火烧岗岩体可能为十字头岩体的分支,深部为一整体,呈单向延伸且具一定规模的不规则岩墙产出;岩石类型主要为似斑状黑云母花岗岩,与Cu、Mo成矿关系密切,属燕山早期;岩体具低Ti、富Si、富Al、低Na、高K、钾玄岩系列和弱过铝质-过铝质的主量元素地球化学特征;稀土元素负Eu、正Eu异常均较明显(Eu/Eu^(*)=0.67~1.23),无明显Ce异常(Ce/Ce^(*)=0.98~1.07);Nb的严重亏损,Th、Sr、P、Zr、Hf、Ti相对亏损,Rb、Ba、U、Sm相对富集。岩体属S型花岗岩,可能为大陆活化造山(局部伸展)背景下,华夏板块向扬子板块俯冲作用过程中上地壳物质部分熔融的岩浆产物。The Yongping copper mine is located in the northern margin of the north Wuyi metallogenic belt.During exploration work in recent years,a molybdenum deposit is founded to coexist in this copper deposit in the deep part of the copper mine,which is closely related to the mineralization of the rock mass.In this paper,the petrology and petrogeochemistry of the Shizitou-Huoshaogang rock mass in the Yongping copper mine are analyzed and studied.The results show that the Huoshaogang rock mass in the Yongping mining area may be a branch of the Shizitou rock mass.In the deep part,the Shizitou rock mass and the Huoshaogang rock mass are connected into a whole,extending in one-way direction and with a certain scale of irregular rock wall output.The rock type is mainly porphyritic-like biotite granite,which is closely related to Cu and Mo mineralization and belongs to the early Yanshanian.The rock mass is characterized by low-Ti,high-Si,high-Al,low-Na,high-K,shoshonite series and weakly peraluminous-peraluminous geochemical characteristics of main elements.The negative and positive Eu anomalies of rare earth elements are obvious(Eu/Eu^(*)=0.67~1.23).There is no obvious Ce anomaly(Ce/Ce^(*)=0.98~1.07).Nb is seriously depleted;Th,Sr,P,Zr,Hf and Ti are relatively depleted;and Rb,Ba,U and Sm are relatively enriched.The rock mass belongs to S-type granite,which may be the magma product because of the partial melting of the upper crust during the subduction of the Cathaysian plate to the Yangtze plate under the background of activated orogeny(local extension).

关 键 词：似斑状黑云母花岗岩 岩石地球化学 岩石成因 构造背景 永平铜矿 

分 类 号：P597[天文地球—地球化学]