蒙古国玛达特地区铜钼及铅锌银矿矿床成因类型探讨
Discussion on the Genetic Type of Cu-Mo and Pb-Zn-AgDeposits of the Madate Area in Mongolia
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摘要: 蒙古国东部玛达特地区地处中蒙古-额尔古纳多金属成矿带,在区域内先后发现查布铅锌银矿床、喇嘛朝鲁图铜钼矿床及萨尔希特铅锌银矿床等一系列多金属矿床。通过对各矿床成矿时代、成矿地质背景及围岩特征等进行综合研究,将区域内成矿期划分为华力西晚期、燕山期两期,铜钼矿床为华力西晚期、燕山早期两期叠加成矿,铅锌银矿床成矿期为燕山晚期,2类矿床成矿与构造、岩浆活动关系密切。同时,通过分析对比各矿床矿化特征、矿体特征等因素,将区域内矿床划分为2种矿床成因类型,即中高温斑岩型铜钼矿床、中温热液脉型铅锌银矿床,喇嘛朝鲁图铜钼矿床及萨尔希特铅锌银矿床成矿母岩微量元素分析结果表明,二者属同一成矿系列,符合斑岩型-浅成热液型矿床成矿模式。Abstract: A lot of polymetallic deposits, including the Chabu Pb-Zn-Ag deposit, Saerxite Pb-Zn-Ag deposit and Lamacaolutu Cu-Mo deposit, have been found in the Madate area of eastern Mongolia, which belongs to central Mongolia-Erguna polymetallic ore belt. Throughcomprehensive study on the mineralization age,the ore-forming geological backgroud and thesurrounding rock characteristics of each deposit,we classify the mineralization period of the area into two stages:Late Variscan and Yanshanian. Copper-molybdenum deposit is superimposed mineralization of the Late Variscan and Early Yanshanian,Lead-zinc-silver deposit was formed in the Late Yanshanian. The mineralization of the two types of deposits is closely related to the tectonic and magmatic activity. At the same time,by analyzing and comparing the mineralization characteristics and orebody characteristics of each deposit,we classify these deposits into two genetic types:porphyry-type Cu-Mo deposit and epithermal low-temperature hydrothermal veintype lead-zinc-silver deposit. Based on the trace element analytic results of the ore-forming source rock of Saerxite Pb-Zn-Ag deposi and Lamacaolutu Cu-Mo deposit,we think two genetic types as a unified metallogenic series and establish the porphyry-epithermal low-temperature hydrothermal vein-type mineralization model.