我国东北部地区大规模低温银成矿特征与机制  

Characteristics and mechanisms of large-scale low-temperature silver mineralization in northeastern China

作　　者：翟德高[1,2] 赵青青 豆明新 许康宁 江玲 吴晋超 吕焕科 ZHAI De-gao;ZHAO Qing-qing;DOU Ming-xin;XU Kang-ning;JIANG Ling;WU Jin-chao;LYU Huan-ke(School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China;State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国地质大学(北京)地质过程与矿产资源国家重点实验室,北京100083

出　　处：《矿物岩石地球化学通报》2024年第4期755-766,I0003,共13页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家自然科学基金资助项目(42122012,41973038);内蒙古自治区自然资源厅地勘基金资助项目(2022-TZH03)。

摘　　要：本文从银成矿地质特征、金属和流体来源、银的迁移富集机制以及低温银成矿与斑岩系统的成因联系等方面,阐述了我国东北部地区大规模低温银成矿作用及其控制机制。我国东北部地区银铅锌矿化赋矿围岩主要以粉砂岩和(碳质)板岩为主,成矿流体具低温和低盐度特征。多元同位素(C-H-O-S-Pb-He-Ar)体系表明成矿流体和金属以岩浆-热液来源为主,高精度年代学研究表明脉状银铅锌矿化与区域燕山晚期早白垩世酸性岩浆活动密切相关,部分矿床的形成还可能与多期热液活动叠加有关。总体上,我国东北部地区脉状银铅锌矿床成因类型应属于浅成低温热液型,与区内的中高温斑岩成矿体系构成同一岩浆-热液系统。流体与围岩的水岩反应导致热液体系发生还原和降温是造成银大量沉淀成矿的关键因素。In this paper,characteristics and mechanisms of large-scale low-temperature silver mineralization developed in northeast(NE)China have been introduced based on investigations of geological characteristics of silver mineralization,metal and fluid sources,migration and enrichment mechanism of silver,and genetic relationship between low-temperature silver mineralization and porphyry system.This study reveals that the host rocks of silver-lead-zinc mineralization in NE China are mainly siltstone and slate,and the ore-forming fluid is characterized by low temperature and low salinity.Multi isotope(C-H-O-SPb-He-Ar)system indicates that the ore-forming fluids and metals are mainly magmatic-hydrothermal origin.High-precision geochronological studies indicate that regional Ag-Pb-Zn mineralization is closely related to the early Cretaceous felsic magmas,and some deposits may be dominated by multiple superimposed hydrothermal events.Overall,the genetic type of the widespread Ag-Pb-Zn deposits in NE China should be classified as epithermal deposits,and those magmatic-hydrothermal ore systems are genetically associated with regional porphyry ore systems.Reduction and cooling of the hydrothermal system caused by fluid-rock interactions are the key mechanisms for silver precipitation.

关 键 词：银铅锌矿床 金属来源 迁移富集机制 低温银成矿系统 东北部地区 

分 类 号：P618.52[天文地球—矿床学]