摘要
宽坪银矿床是位于华北地块南缘崤山地区的蚀变岩型矿床。本文对宽坪矿床开展流体包裹体、稳定同位素研究,结果显示:宽坪银矿床成矿阶段分为Ⅰ期、Ⅱ期和Ⅲ期,Ⅰ期LV型包裹体均一温度为151℃~330℃,平均为252℃,盐度为8.5%~16.4%,平均盐度为12.63%,流体具有中等盐度和低密度的特性,推测Ⅰ期成矿热液应为岩浆热液-变质热液的混合;Ⅱ期LV型包裹体均一温度为145℃~316℃,平均为216℃,盐度为0.19%~18%,平均为6.13%,较Ⅰ期温度平均下降36℃,盐度平均下降6.5%,推测Ⅱ期成矿热液应为变质热液-岩浆热液-雨水的混合;Ⅲ期成矿流体包裹体均一温度为136℃~265℃,平均为192℃,盐度范围为0.18%~16%,平均为7.73%,Ⅲ期成矿温度较Ⅱ期平均下降24℃,支持大气水的混入,但流体盐度较Ⅱ期略升,可能跟岩浆流体减弱、变质流体成矿作用增大有关,推测Ⅲ期成矿热液应为变质热液-雨水的混合。综合分析认为:(1)宽坪银矿床成矿期成矿温度为中低温;(2)成矿流体主要来自岩浆热液,后期有变质热液与雨水的混入,成矿物质主要来自岩浆带上来的深源物质。
The Kuanping silver deposit is an alteration-rock type deposit in Xiaoshan area of southern margin of the North China block.The result of the present study on fluid inclusion and stable isotope from the Kuanping deposit showed that the ore-forming period of Kuanping silver deposit can be divided into stageⅠ,Ⅱand Ⅲ,and the homogenization temperature of LV inclusion in stageⅠ was from 151℃ to 330℃,with an average of 252℃.The salinity was from 8.5 to 16.4 with an average of 12.63.The fluid had the characteristics of medium salinity and low density.It was inferred that the ore-forming hydrothermal solution of the stageⅠshould be a mixture of magmatic hydrothermal fluid and metamorphic hydrothermal solution.The homogenization temperature of LV type inclusion in stage Ⅱ was from 145℃ to 316℃ with an average of 216℃.The salinity was from 0.19 to 18 with an average of 6.13.The average temperature and average salinity of stage II was respectively 36℃and 6.5 lower than that of stage I.It was inferred that the ore-forming hydrothermal solution of stageⅡ should be a mixture of metamorphic hydrothermal fluid,magmatic hydrothermal fluid and rain water.The homogenization temperature of ore-forming fluid inclusions in stage Ⅲ was from 136℃to 265℃ with an average of 192℃.The salinity rangeed from 0.18 to 16 with an average of 7.73.The ore-forming temperature of stageⅢ was 24℃lower than that of stageⅡ,which supported the mixing of atmospheric water,but the fluid salinity was slightly higher than that of stageⅡ,which might be related to the weakening of magmatic fluid and the increase of mineralization of metamorphic fluid.It was inferred that the ore-forming hydrothermal solution of stageⅢshould be the mixture of metamorphic hydrothermal solution and rain water.It was considered that the ore-forming fluid of Kuanping silver deposit was mainly derived from magmatic hydrothermal fluid and mixed in with the metamorphic hydrothermal fluid and rain water in the late stage,and the ore-forming material mainly came from deep source of magma.
作者
索勇
徐书奎
SUO Yong;XU Shukui(The First Geological Team of Henan Bureau of Nonferrous Metals Geology and Mineral Resources Zhengzhou 450016,Henan,China;Nonferrous Metal Mineral Exploration Engineering Technology Research Center Zhengzhou 450016,Henan,China)
出处
《矿产与地质》
2018年第2期189-196,共8页
Mineral Resources and Geology
基金
河南省两权价款地质科研项目(任务书豫国土资函[2015]258号
编号:04)
河南省有色金属地质矿产局科研项目(编号:YSDK2014-04)共同资助
关键词
银矿
稳定同位素
成矿流体
均一温度
宽坪
豫西
Kuanping silver deposit
stable isotope
ore forming fluid
homogenization temperature
western Henan
