摘要
长城金矿区位于冷口断裂北部,矿体主要赋存于杨庄组蚀变白云岩及部分蚀变闪长玢岩岩脉中,主要受断裂或构造破碎蚀变岩带控制。金赋存状态为裂隙金、粒间金和包裹金,除少量显微金外,存在较多的“不可见金”(粒度<0.1μm),Ag、Cu、As元素与Au的相关性高。成矿期划分为热液期和表生氧化期。包裹体测温显示:长城金矿形成于浅成环境,属于中—低温度低盐度流体体系。本文通过C-H-O-S同位素研究表明:成矿流体来自岩浆水混合大气降水,成矿物质主要来自花岗岩或是闪长玢岩类岩体。根据前人研究可知成矿时代为早白垩世,成矿作用与花岗岩或闪长玢岩类岩体关系密切。矿床成因类型:与隐爆角砾岩型金矿床有关的深部浅成岩浆柱前锋液压致碎(裂)构造蚀变岩型金矿床,也可认为是类卡林型金矿。
The Changcheng gold deposit area is located in the northern part of the Lengkou fault,and the ore body is mainly located in the altered dolomite of Yangzhuang Formation and some altered diorite porphytite dikes.It is mainly controlled by faults or structural deformation and metamorphic alteration zones.The occurrence state of gold is fissure gold,intergranular gold and encapsulated gold.Beside a small amount of microscopic gold,there are more"invisible gold"(particle size<0.1μm),and Ag,Cu,and As elements are highly correlated with Au.The metallogenic stage is divided into hydrotheral stage and supergene oxidation stage.The temperature measurement of the inclusions shows that the Changcheng gold deposit formed in a shallow environment and belongs to a medium-low temperature and low salinity fluid system.Through the study of C-H-O-S isotopes,it can be concluded that the ore-forming fluid comes from magmatic water mixed with atmospheric precipitation,and the ore-forming minerals mainly come from granite or diorite porphyrite.According to previous studies,the metallogenic age is Early Cretaceous,and the mineralization is closely related to granite or diorite porphyrite.The type of ore deposit is the deep epithermal magmatic column front hydraulically fractured structure altered rock type gold deposit related to cryptoexplosibe brecia type gold deposit,which can also be considered as Carlin-type gold deposit.
作者
杨双江
丁萍
赵靖雯
孙仲坤
杨爱雪
YANG Shuangjiang;DING Ping;ZHAO Jingwen;SUN Zhongkun;YANG Aixue(The Fifth Geological Brigade of Hebei Bureau of Geology and Mineral Resource Exploration,Tangshan 063000,Hebei,China;Marine Geological Environment Survey Center of Hebei Province,Tangshan 063000,Hebei,China)
出处
《矿产勘查》
2025年第8期1985-1998,共14页
Mineral Exploration
基金
河北省自然资源厅专项资金项目“河北省迁安市长城金矿外围地质普查”(454-0502-YBN-HWP8)
河北省地质矿产勘查开发局科研项目“冀东高板河—清河沿一带中上元古界地层成矿规律研究”(454-0502-YBN-DTDP)
河北省地质矿产勘查开发局科研项目“冀东冷口金成矿带成矿模型建立及找矿方向研究”(454-0601-YBN-FAA0)联合资助。
关键词
断裂构造
包裹体
同位素
矿床成因
长城金矿床
河北迁安
fault structure
inclusions
isotopes
ore deposit genesis
Changcheng gold deposit
Qian'an,Hebei Province
