摘要
黑龙江乌拉嘎金矿床位于兴蒙-天山造山带东缘吉黑褶皱系佳木斯隆起北端的太平沟隆起与嘉荫凹陷东侧乌拉嘎断裂的结合处。该金矿是在乌拉嘎深断裂控制作用下产生的大型原生岩金矿床,其矿床成因认识逐渐清晰;从次火山热液型、斑岩型金矿床、热泉型浅成低温热液金矿床,到现在认为的典型的浅成低温热液型金矿。乌拉嘎金矿床主矿体就位于斜长花岗斑岩与黑龙江岩群片岩的接触部位靠近斑岩一侧。金矿的成矿年龄为晚燕山期;矿区西部构造破碎岩带发育,为矿床的就位提供了良好的场所。岩浆期后热液和大气降水共同影响着矿床的形成。矿石结构以细粒状、碎裂、胶状为主,矿石构造以脉状、角砾状为主;矿床围岩蚀变发育。以矿体为中心,从矿床外围向矿床内部依次发育有碳酸盐化-泥化-绢云母化-冰长石化-硅化,矿体就位的围岩蚀变以及围岩蚀变的含矿性都揭示硅化蚀变作用是乌拉嘎金矿成矿的关键因素。目前尾采阶段的零星矿体主要就位于花岗斑岩的构造裂隙带附近,黄铁矿化不明显。因此要揭示这类具斑岩成矿特征的浅成低温热液型矿床的成因还需要更直接的佐证,或许花岗斑岩斜长石铝含量与斑岩型铜矿的关系能为解决这个问题提供可借鉴的思路。
The Wulaga gold deposit of Heilongjiang lies at the conjunction of the Taipinggou uplift and Jiayin depression, north of the Jiamusi uplift of the Jihei fold system in the Xingmeng-Tianshan orogen. It is controlled by the deep Wulaga fault. From the discovery of this large-scale deposit to present, various models on its genesis have been proposed, such as the subvolcanic hydrothermal type （Liu, 1972）, porphyry type gold deposit （Wei et al., 1983; Wu, 1984）, hot spring type shallow cryogenic hydrothermal gold deposit （Zhang et al., 1992）, and the typical low sulfadation epithermal gold deposit （Sun et al., 2008）. The main orebodies of this deposit are located in the contact belt between slate of Heilongjiang Group and the plagioclase granite porphyry. Its mineralization occurred during the Late Yanshan period. Many broken-rock zones developed in the west of the deposit area, serving as a good place for ore deposition. The post-magma hydrothermal fluids and meteoric water posed influence on the generation of the deposit. The structure of the ore is dominated by fine-grained, fragmentation and gel-like, vein-like and breccia-like features. The alteration of the surrounding rock is very obvious. Centered by the ore body, from the periphery to the interior of the deposit are carbonation, argillation, sericitization, adularization, and silicification, respectively. The alteration of the surrounding rock and its ore-bearing nature reveal that silicated alteration is the key factor for the mineralization of the Wulaga gold deposit. At present, the sporadic ore bodies in the tail mining stage are mainly located near the structural fracture zone of the granite porphyry, and the pyrite mineralization is not obvious. Therefore, more lines of evidence are needed to elucidate the genesis of this epithermal deposit characterized by porphyry mineralization. The relationship between the aluminum content in the plagioclase granite-porphyry and the porphyry copper deposit may be a useful clue to help address this issue.
作者
高天
郭洋
陈彩云
刘福林
李永兵
刘建明
石耀霖
GAO Tian1, GUO Yang1, CHEN Cai-yun1, LIU Fu-lin2 , LI Yong-bing1, LIU Jian-ming3 , SHI Yao-lin1(1. University of Chinese Academy of Sciences, Beijing 100049; 2. Inner Mongolia Jintao Corporation Limited, Chifeng, Inner Mongolia 024327;3. Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002)
出处
《地质与勘探》
CAS
CSCD
北大核心
2018年第2期243-251,共9页
Geology and Exploration
基金
中国黄金黑龙江乌拉嘎金矿成矿特征床成矿特征与成矿潜力评价研究和基金重点项目(编号:No.41530315)资助
关键词
乌拉嘎断裂
金矿床
晚燕山期
裂隙充填
浅成低温热液
黑龙江
Wulaga fault, gold deposit, Late Yanshanian period, fissure filling,epithermal low-temperature hydrothermal fluid, Heilongjiang Province
