摘要
大别山北麓地质构造复杂,岩浆活动强烈,桐-商深大断裂对萤石矿控矿作用显著,燕山期中酸性花岗岩与区内萤石矿关系密切。萤石流体包裹体中δ^18 O变化范围为1.14‰~13.78‰、δD为-110.8‰^-68.4‰;共伴生黄铁矿、方铅矿,δ^34 S/δ^32 S比值变化范围为-19.271‰~1.707‰,206 Pb/204 Pb比值为16.655~16.850、207 Pb/204 Pb比值为15.324~15.398、^208 Pb/^204 Pb比值为37.514~37.993;流体包裹体均一温度均值为133℃,盐度w(NaCleq)平均值为4.70%,密度平均值为0.97 g/cm^3。综合研究认为:氢、氧同位素显示萤石中成矿流体为岩浆水、变质水为主,大气降水参与的混合成矿热液;硫同位素显示硫源较复杂,铅同位素显示铅源主要来自下地壳重熔岩浆及部分上地幔的铅混入;成矿流体主要为低温低盐度、较低密度的热液流体,矿床类型多属于热液充填型萤石矿床。
The North Dabie Mountains are characterized by complex geological structure and intense magmatic activity.The Tongbo-Shangcheng deep fault has a remarkable ore-controlling effect on fluorite deposits,which are closely related to the Yanshanian intermediate-acid granite in the area.Theδ^18 O andδ^D of the fluid inclusion of fluorite range from 1.14‰to 13.78‰and from–110.8‰to–68.4‰,respectively.The pyrite and galena are associated with the fluorite.Theδ^34 S/δ^32 S ratio ranges from–19.271‰to 1.707‰.The ratios of^206 Pb/^204 Pb,^207 Pb/^204 Pb and^208 Pb/^204 Pb range from 16.655 to 16.850,from 15.324 to 15.398,and from 37.514 to 37.993,respectively.The average homogeneous temperature of fluid inclusion is 133℃,the average salinity is 4.70%NaCl and the average density is 0.97 g/cm^3.On the basis of the above comprehensive study,it is considered that hydrogen and oxygen isotopic features show that the metallogenic fluids in fluorite deposits are mixed mineral hydrothermal fluids of mainly magmatic water and metamorphic water,and participated with less atmospheric precipitation.Sulfur isotopic feature shows that sulfur sources are more complex,and lead isotopic feature shows that lead sources mainly come from lead mixing of lower crust remelting magma and part of the upper mantle.The ore-forming fluids are mainly low temperature,low salinity and low density hydrothermal fluids.Most of the fluorite deposits belong to hydrothermal filling type.
作者
索忠连
王双
余智慧
李玉芹
袁要伟
王晓黎
SUO Zhonglian;WANG Shuang;YU Zhihui;LI Yuqin;YUAN Yaowei;WANG Xiaoli(The 7th Geological Team of Henan Province Non-ferrous Metals Geological and Mineral Resources Bureau,Zhengzhou 450016,Henan,China;Henan Research Centre of Mineral Exploration Engineering and Technology for Non-ferrous Metals Resources Zhengzhou 450000,Henan,China)
出处
《矿产与地质》
2020年第1期41-47,共7页
Mineral Resources and Geology
基金
2017年度河南省国土资源科研项目“河南省大别山地区萤石矿成矿规律及选区研究”(编号:2017-06)资助。
关键词
萤石矿床
同位素特征
大别山北麓
fluorite deposit
isotopic characteristics
North Dabie Mountains
