投稿时间：2011-11-17
修订日期：2012-08-03
中文摘要:华尖金矿床是冀东地区典型的石英脉型金矿床之一,金主要产在多金属硫化物石英脉中。流体包裹体研究表明,该金矿床各成矿阶段矿石中的流体包裹体主要有3种类型:H2O-CO2包裹体、H2O溶液包裹体和含子晶多相包裹体。成矿早期的流体为H2O-CO2-NaCl体系,均一温度为320℃左右;主成矿阶段的流体为H2O-NaCl体系,均一温度为280℃左右,不混溶作用以及控矿构造由挤压向拉张的转换是金沉淀的主要原因。氢、氧同位素研究表明,华尖金矿床主成矿期流体既有岩浆水又有大气降水参与,成矿晚期流体是以大气降水为主的混合流体。硫、铅同位素示踪表明,该矿床内的金主要来自在深部重熔的太古宙变质岩,成矿物质直接来源为牛心山花岗岩,间接来源于太古宙遵化群变质岩系,成矿过程与下地壳或上地幔物质的演化和改造有关。华尖金矿床的形成与燕山陆内造山作用的伸展期构造及侵入作用有关,岩浆活动带来了稳定的热源和大量的含金流体,随着成矿流体物理化学性质的改变,含金硫化物在张性构造部位沉淀成矿。
Abstract:The Huajian gold deposit is a typical quartz vein type gold deposit in eastern Hebei Province, and gold occurs mainly in polymetallic sulfide-quartz veins. Fluid inclusion studies show that there are three major types of fluid inclusions in gold ores of different ore-forming stages, i.e., H2O-CO2 inclusions, aqueous fluid inclusions and high-salinity inclusions with daughter minerals. Microthermometic and Laser Raman spectrum analyses indicate that the H2O-CO2-NaCl fluid system of the early stage changed into the H2O-NaCl fluid system at the main metallogenic stage, with the peak value of homogenization temperatures reduced from 320℃ to 280℃. Ore-controlling structures from compression to extension and fluid immiscibility seem to be the main factors for gold precipitation. Hydrogen and oxygen isotope studies suggest that at the ore-forming stage the mineralizing fluids were mainly magmatic water, but at the end of the ore-forming process the mineralizing fluids became mixed fluids mainly due to the addition of meteoric water. Characteristics of sulfur and lead isotopes show that Au mainly came from the anatexis of Archean metamorphic rocks. The direct and indirect sources of ore materials were Niuxinshan garnites and Archean Zunhua Group respectively. The mineralization was related to deep magmatic activation. There existed direct genetic relation between the gold mineralization and the intrusion and stretching structure in Yanshanian intracontinental orogenesis. The magmatic activity brought stabilized thermal energy and Au-bearing fluid. Gold precipitated in the favorable fracture with the physical and chemical changes of the ore-forming fluid.
keywords:geochemistry fluid inclusion isotope gold deposit Huajian eastern Hebei Province (Jidong area)
文章编号：
中图分类号：P618.51
文献标志码：
基金项目:本文得到全国危机矿山接替资源找矿专项典型矿床研究项目(编号: 200899363)资助
引用文本：
宋扬,王瑞江,胡建中,王小龙,孙艳,辛洪波,武晗.2012.冀东华尖金矿床流体包裹体特征与成矿作用研究[J].矿床地质,31(6):1289~1300SONG Yang,WANG RuiJiang,HU JianZhong,WANG XiaoLong,SUN Yan,XIN HongBo,WU Han.2012.Fluid inclusion characteristics and metallogenic evolution of Huajian gold deposit in eastern Hebei Province[J].Mineral Deposits31(6):1289~1300
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