摘要
【研究目的】云南省中甸地区燕山晚期是格咱岛弧最重要的斑岩型Mo多金属成矿时期,本文选择该区铜厂沟大型斑岩型钼铜矿Ⅳ号花岗闪长斑岩体作为研究对象,尝试揭示斑岩体在矿化蚀变过程中元素迁移规律和围岩蚀变与成矿的关系。【研究方法】本文对Ⅳ号花岗闪长斑岩体原岩及不同蚀变带岩分别做了主量、微量及稀土元素分析,运用标准化Isocon方法对主量、微量及稀土元素进行了质量平衡及迁移量计算分析。【研究结果】斑岩体矿化蚀变有钾硅酸盐化、绢英岩化、青磐岩化等,各个蚀变带中主要迁入Si O_(2)、K_(2)O、挥发分等主量元素,大量迁出Na_(2)O;而Al_(2)O_(3)、Ti O_(2)、P_(2)O_(5)等主量元素和Zr、Nb、Hf、Th、Ta等高场强元素及稀土元素迁移活动性差,为惰性组分;Cu、Pb、Zn、Ag等成矿元素和Sb、As指示元素具有大量外迁的趋势,反映岩体外围具有找相关矿种的潜力;绢英岩化带与Mo成矿关系最为密切,其次为钾硅酸盐带;Mo与Cu二者具有不同的沉淀致矿机制,前者主要受“酸碱度转换障”控制,后者受“硅钙面”和“后生构造界面”控制;该斑岩体规模小,Mo背景值低,然其迁入量达3000%以上,约30%岩体为钼矿体,暗示深部岩浆房对成矿贡献巨大。【结论】本次工作为铜厂沟矿床的成矿物质来源、成矿作用研究和找矿勘查提供了地质参考依据。
This paper is the result of mineral exploration engineering.[Objective]The late Yanshannian epoch was the most important period of multi-metal mineralization of porphyry Mo at the Geza island arc in Zhongdian area,Yunnan province.In this paper,we chose the No.IV granitic diorite porphyry body of Tongchanggou large-scale porphyry molybdenum-copper deposit in this area as the research object,attempting to reveal the elemental migration rule of porphyry body in the process of mineralized alteration and the relationship between the peripheral rock alteration and mineralization.[Methods]In this paper,the major elements,trace elements and rare earth elements in the original rock and the rocks in different alteration zones of No.IV granodiorite porphyry are analyzed respectively.The mass balance and migration amount of these major elements,trace elements and rare earth elements are calculated and analyzed by using the normalized Isocon method.[Results]The results show that K-silicate alteration,sericite-quartz alteration,and propylitization were involved in the process of the mineralization and alteration of the porphyry body,and SiO_(2),K_(2)O and volatile matters are major elements migrating in the alteration zones while a large amount of Na2O migrated out;while major elements such as Al_(2)O_(3),TiO_(2)and P_(2)O_(5),and high field strength elements such as Zr,Nb,Hf,Th and Ta,and rare earth elements all present poor migration activity,belonging to inert components;mineralizing elements such as Cu,Pb,Zn and Ag,and indicator elements such as Sb and As show a trend to migrate out,reflecting the potential to find relevant types of ore around the rock body;the sericite-quartz zone is the most closely related to Mo mineralization,followed by K-silicate alteration;the deposition and mineralization mechanism of Mo is different from that of Cu,the former is mainly under the control of“converted barrier of pH”,and the latter is under the control of“silicon-calcium surface”and“epigenetic structure interface”;this po
作者
李守奎
陈建航
刘学龙
张世涛
李振焕
LI Shoukui;CHEN Jianhang;LIU Xuelong;ZHANG Shitao;LI Zhenhuan(Faculty of Land Resource Engineering,Kunming University of Science and Technology,Kunming 650032,Yunnan,China;Faculty of Engineering Technology,Baoshan University,Baoshan 678000,Yunnan,China)
出处
《中国地质》
CSCD
北大核心
2023年第6期1745-1763,共19页
Geology in China
基金
云南黄金集团校企合作项目(KKF0202121292)
国家自然科学基金项目(42362010)
昆明理工大学“双一流”科技专项课题(202202AG050006-2)
云南省高层次科技人才及创新团队选拔专项(202305AT350004-4)
云南省三江成矿系统与评价顶尖团队培育项目(202305AS350015)联合资助。
关键词
铜厂沟钼铜矿
质量平衡
标准化Isocon图解法
元素迁移
围岩蚀变
矿产勘查工程
云南
Tongchanggou porphyry Mo-Cu deposit
mass balance
normalized Isocon diagram method
element transfer
wall-rock alteration
mineral exploration engineering
Yunnan Province
