摘要
兴蒙造山带位于中亚造山带东段,形成于古生代,在中生代遭受了西北部蒙古-鄂霍茨克洋构造域和东部古太平洋构造域的强烈改造。该造山带也是中国北方地区一个重要的金属成矿带,因此对该造山带成矿规律的总结和研究,无论是在理论上还是在找矿勘查实践中都具有十分重要的意义。笔者对该地区的研究成果进行了收集和整理。根据已有的年代学数据,该区已发现的绝大多数矿床形成于侏罗纪—白垩纪,与古生代古亚洲洋构造体系关系不大。根据兴蒙造山带内的成矿与不同构造体系演化之间的关系,将研究区内的矿床分为4类:(1)与古亚洲洋构造体系有关的矿床,形成于500~210 Ma,矿床类型主要是斑岩型Cu-Mo、Mo和Au矿床、浅成低温热液型Au矿床和矽卡岩型Pb-Zn矿床,矿床形成环境主要为岛弧及古亚洲洋闭合后的碰撞与伸展阶段;(2)与蒙古-鄂霍茨克洋构造体系有关的矿床,形成时间240~110 Ma,矿床类型主要是斑岩型Cu-Mo和Mo多金属矿床、浅成低温热液型Au矿床、中低温热液脉型Pb-Zn-Ag矿床和热液脉型Ag多金属矿床,形成环境主要为陆缘弧、蒙古-鄂霍茨克洋闭合后的碰撞造山-后碰撞,以及造山后的伸展崩塌阶段;(3)与古太平洋构造体系有关的矿床,成矿作用发生于210~100 Ma,矿床类型主要有斑岩型Mo(W、Cu)矿床、矽卡岩型多金属矿床和浅成低温热液型Au矿床,形成于与古太平洋板块俯冲有关的活动大陆边缘环境;(4)与蒙古-鄂霍茨克洋和古太平洋构造体系叠加有关的矿床,矿床主要形成于150~120 Ma,矿床类型主要有斑岩型Mo(Cu、W)矿床、热液脉型Pb-Zn-Ag和Cu多金属矿床、高温岩浆热液型稀有稀土元素、W(Sn)、Sn矿床和矽卡岩型Fe多金属矿床,矿床形成环境处于蒙古-鄂霍茨克洋和古太平洋这两大构造体系的叠加区域,总体属于一个伸展的构造背景。不同构造体系下的成矿特点是不同的,而所富集的主要金属元素也有差别。根据所产出的不同金属的资源量大小对比,Cu主要产在与古亚洲洋构造体系和蒙古-鄂霍茨克洋构造体系,Mo主要产在蒙古-鄂霍茨克洋构造体系和古太平洋构造体系,Pb-Zn主要产在蒙古-鄂霍茨克洋和古太平洋构造体系叠加区和古亚洲洋构造体系,Au主要产在古太平洋构造体系,Ag和Sn主要产在蒙古-鄂霍茨克洋和古太平洋构造体系叠加区,W主要产在蒙古-鄂霍茨克洋和古太平洋构造体系叠加区域和古太平洋构造体系。
Located in the eastern part of the Central Asian Orogenic Belt, the Xing-Meng orogenic belt was formed in the Paleozoic, and was strongly modified by the Mongol-Okhotsk ocean tectonic system to the northwest and Paleo-Pacific tectonic system to the east in the Mesozoic. It is also an important metallogenic belt in northern China, so the research on the metallogeny of the Xing-Meng orogenic belt is of great significance in both theory and mineral exploration. In this study, the authors collected and summarized the results from previous researchers. The available age data show that most ore deposits in this region were formed in Jurassic and Cretaceous, and had little to do with the Paleo-Asian Ocean tectonic system. According to the relationship between the mineralization and evolution of different tectonic systems in the Xing-Meng Orogenic Belt, the ore deposits there could be divided into four categories：① The ore deposits related to the Paleo Asian Ocean tectonic system, which were formed in 500-210Ma, with the major type of ore deposits being porphyry Cu-Mo, Mo and Au, epithermal Au, and skarn type Pb-Zn deposits in a tectonic setting of mainly island arc and collision-extensional stage after the closure of the Paleo-Asian Ocean; ② The ore deposits related to the Mongol-Okhotsk Ocean tectonic system, which were formed during 240-110Ma, with the main types of ore deposits consisting of porphyry Cu-Mo and Mo polymetallic, epithermal gold, meso-epithermal vein type of Pb-Zn-Ag, and hydrothermal vein type of Agpolymetallic deposits, which were formed under the setting of continental margin arc, collision and post-collision after the closure of the Mongol-Okhotsk ocean, and the extensional collapse stage; ③ The ore deposits related to the Paleo-Pacific tectonic system, which occurred between 210 and 100Ma, with the main types of ore deposits composed of porphyry Mo （W, Cu）, skarn polymetallic, and epithermal Au deposits, which were formed in a setting of active continental margin related to the subduction of Paleo-Pacific plate; ④ The ore deposits related to the superimposition of the Mongol-Okhotsk Ocean and Paleo-Pacific tectonic systems, which were predominantly formed during 150-120Ma, with the main types of ore deposits composed of porphyry Mo （Cu, W）, hydrothermal vein-type Pb-Zn-Ag and Cu-polymetallic, hypothermal rare and REE elements, W （Sn）, and Sn, and skarn Fepolymetallic deposits, which were formed under an extensional tectonic background in the superposition region of the Mongol-Okhotsk Ocean and Paleo-Pacific tectonic system. Thus, the metallogenic features in different tectonic systems are different, and the mainly enriched metal elements are also different. According to the comparison of the different metal resources in these tectonic systems, Cu mainly occurred in the Paleo-Asian Ocean and the Mongol-Okhotsk Ocean tectonic systems; Mo was predominantly enriched in the Mongol-Okhotsk Ocean and Paleo-Pacific tectonic system; Pb-Zn mainly occurred in the superimposed area of the Mongol-Okhotsk Ocean and Paleo-Pacific tectonic system and the Paleo-Asian Ocean tectonic system; Au was mainly enriched in the Paleo-Pacific tectonic system; Ag and Sn mainly occurred in the superimposed area of the Mongol-Okhotsk Ocean and the Paleo-Pacific tectonic system; W was mainly enriched in the superimposed area of the Mongol-Okhotsk Ocean and the Paleo-Pacific tectonic system as well as the Pale-Pacific tectonic system.
作者
江思宏
张莉莉
刘翼飞
刘春花
康欢
王丰翔
JIANG SiHong;ZHNG LiLi;LIU YiFei;LIU ChunHua;KANG Huan(MNR Key Laboratory of Metallogeney and Mineral Assessment,Institute of Mineral Resources,CAG S,Beij ing 100037,China;School of Earth and Space Science,Peking University,Beijing 100871,China)
出处
《矿床地质》
CAS
CSCD
北大核心
2018年第4期671-711,共41页
Mineral Deposits
基金
国家重点研发计划项目(编号:2017YFC0601303)
国家重点基础研究发展计划"973"项目(编号:2013CB429805)
国家自然科学基金项目(编号:41273061)
科技基础性工作专项项目(编号:2014FY121000)
中国地质科学院基本科研业务费项目(编号:YYWF201715)资助
关键词
地质学
构造体系
成矿年龄
成矿规律
兴蒙造山带
geology
Tectonicsystem
ore-formingage
metallogeny
Xing-Mengorogenicbelt
