投稿时间：2014-08-31
修订日期：2014-10-11
网络发布日期：2014-12-30
中文摘要:冀东唐杖子金(钼)矿床地处华北陆块北缘燕山造山带的东段,该区主要出露太古宙和中-新元古代地层,岩浆岩主要为中生代花岗斑岩。钼矿体主要产于隐爆角砾岩中,辉钼矿呈浸染状、薄膜状、网脉状和胶结物产出;金矿体产于隐爆角砾岩和断裂带中,矿化类型有隐爆角砾岩型、石英脉型和构造蚀变岩型。为了厘定唐杖子金(钼)矿床的成矿时代、成矿物质来源,以及与区域上金矿的关系,笔者采用辉钼矿Re-Os同位素定年方法,获得6件辉钼矿样品的模式年龄主要介于(168.1±2.5) Ma~(171.5±2.8) Ma,加权平均年龄为(170.0±1.0) Ma(MSWD=0.80),等时线年龄为(170.1±1.6) Ma,表明唐杖子金(钼)矿床和矿区花岗斑岩均形成于中侏罗世,成矿物质来源为壳幔混源,同区域上峪耳崖、牛心山等金矿床的成矿时代一致,是华北陆块北缘早燕山期大规模岩浆活动-成矿作用的产物。中侏罗世花岗质岩浆沿F4Ⅰ主干断裂侵入,在顶部岩层发生隐爆,形成潜火山机构,成矿流体沿角砾岩筒及断裂系统迁移、富集、成矿。唐杖子金(钼)矿床为与花岗斑岩-隐爆角砾岩侵入有关的隐爆角砾岩型钼金矿-脉状金矿床。
Abstract:The Tangzhangzi gold (molybdenum) deposit is located in eastern Yanshan orogenic belt of the North China Craton. Archean and Meso-Neoproterozoic strata are exposed in this area, and the magmatic rocks are mainly the Mesozoic granite, controlled by the subvolcanic apparatus. The molybdenum orebodies are hosted in the cryptoexplosion breccia, and the molybdenite occurs in the forms of dissemination, lamination, stockwork and cements. The gold orebodies mainly occur in the cryptoexplosion breccia and the fault zone. The gold ores have three different types, namely cryptoexplosive breccia type, polymetallic sulfide-quartz vein type and tectonic altered rock type. In order to determine the metallogenic epoch of gold and molybdenite, source of ore-forming materials and the relationship of this deposit with the gold deposits in this area, the authors selected six molybdenite-bearing samples from breccia for precise Re-Os dating by using ionic mass spectrographs as inductance coupling and, as a result, yielded model ages ranging from (168.1±2.5) Ma to (171.5±2.8) Ma, with a weighted mean age of (170.0±1.0) Ma(MSWD=0.80) and an isochron age of (170.1±1.6) Ma. These data indicate that the Tangzhangzi gold (molybdenum) deposit formed in the middle Jurassic, consistent with the age of granite porphyry and the metallogenic epoch of the Yuerya and Niuxinshan gold deposits. The ore-forming metals were derived from the mixture of the crust and the mantle, and the ore deposit was a product of early Yanshanian large-scale mineralization on the northern margin of the North China Craton. Granitic magma invaded along the main fracture F4Ⅰ in Middle Jurassic and cryptoexplosion took place at the top of the strata, forming subvolcanic apparatus. Ore-forming fluid migrated, concentrated and resulted in mineralization along the cryptoexplosion breccia pipe and fracture system. The Tangzhangzi gold (molybdenum) deposit belongs to cryptoexplosive breccia molybdenum-gold-vein type gold deposit connected with granite porphyry-cryptoexplosive breccia apparatus.
keywords:geochemistry deposit characteristics Re-Os isotopic age molybdenite Tangzhangzi eastern Hebei
文章编号：
中图分类号：P618.51;P618.65
文献标志码：
基金项目:本文得到国土资源部成矿作用与资源评价重点实验室开放研究项目(编号: ZS1309)和地质大调查项目(编号: 1212011220492)联合资助
引用文本：
李正远,叶会寿,贺文,曹晶,张兴康,王赛,路东宇,李超.2014.冀东唐杖子金(钼)矿床地质特征及辉钼矿Re-Os同位素年龄[J].矿床地质,33(6):1366~1378LI ZhengYuan,YE HuiShou,HE Wen,CAO Jing,ZHANG XingKang,WANG Sai,LU DongYu,LI Chao.2014.Geological characteristics and molybdenite Re-Os isotopic dating of Tangzhangzi gold (molybdenum) deposit in eastern Hebei Province[J].Mineral Deposits33(6):1366~1378
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