全文快速搜索:          
引用本文:刘 坤1, 2 刘家军1 吴 杰1 杨尚松1 辛晓军3 李 渊3. 甘肃马坞金矿成矿流体特征及地质意义[J]. 中国地质, 2014, 41(5): 1594-1607.
LIU Kun1, LIU Jia-jun1, LI Jing-xian1, YANG Shang-song1, XIN Xiao-jun2, LI Yuan2. Fluid inclusion characteristics of the Mawu gold deposit in Gansu Province and their geological significance[J]. Geology in China, 2014, 41(5): 1594-1607(in Chinese with English abstract).
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  下载PDF阅读器  关闭
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 1520次   下载 3048 本文二维码信息
码上扫一扫!
分享到: 微信 更多
甘肃马坞金矿成矿流体特征及地质意义
刘 坤1, 2 刘家军1 吴 杰1 杨尚松1 辛晓军3 李 渊31,2,3
1.地质过程与矿产资源国家重点实验室 中国地质大学地球科学与资源学院, 北京 100083;2.河南省地质调查院, 河南 郑州 450001;3. 中国人民武装警察部队黄金第五支队, 陕西 西安 710100
摘要:
提要: 位于西秦岭岷(县)—礼(县)成矿带西段的马坞金矿床, 是近年发现的一个中型卡林型金矿床。矿体产出受NWW向断裂构造控制, 其赋矿围岩为中泥盆统的千枚岩与灰岩。矿床流体包裹体研究表明, 脉石矿物中主要发育CO2-H2O型和H2O溶液型包裹体; 均一温度为135~389 ℃, 盐度为4.4%~15.9%, 为中-低温、中-低盐度流体; 流体成矿压力为34.6~219.8 MPa, 成矿深度为1.3~8.1 km。流体包裹体气相成分以H2O、N2为主, 其次为CO2、O2, 并含有少量CH4、CO等还原性气体; 液相成分中阳离子以Ca2+、Na+为主, 阴离子以Cl-和SO42-占主导地位, 成矿流体为N2-H2O-Ca2+-Cl-体系。氢氧同位素测试结果表明, 成矿流体的δ18O水为5.3‰~10.5‰, δD为-123‰~-93‰, 成矿流体主要为热卤水。从流体性质及其演化来看, 构造体制的转换使流体稳定体系发生改变与沸腾作用是造成金富集成矿的主要因素。
关键词:  金矿  流体包裹体  氢氧同位素  马坞  甘肃
DOI:
分类号:
基金项目:国家自然科学重点基金 (41030423)、中国地质调查局地质调查工作项目 (1212011220805,1212011220924)、中国人民武装警察部队武警黄金地质研究所项目(WHY(05)-03) 、高等学校学科创新引智计划(B07011)联合资助。
Fluid inclusion characteristics of the Mawu gold deposit in Gansu Province and their geological significance
LIU Kun1, LIU Jia-jun1, LI Jing-xian1, YANG Shang-song1, XIN Xiao-jun2, LI Yuan2
1. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China;2. No. 5 Gold Geological Party of Chinese Armed Police Force, Xi'an 710100, Shanxi, China
Abstract:
Abstract: Located in the western part of the Min-Li metallogenic belt within the West Qinling Mountains, the Mawu gold deposit is a medium Carlin-type disseminated gold deposit discovered in recent years. The orebody is controlled by the NW-trending faults and hosted in the Devonian phyllite and limestone. Two main types of fluid inclusions, i.e., CO2-H2O inclusions and aqueous fluid inclusions, are trapped in the gangue minerals. The homogenization temperatures range from 135 °C to 389 °C, while the salinities range from 4.4% to 15.9%, indicating medium-low temperature and medium-low salinity. The trapping pressures are 34.6 MPa to 219.8 MPa. The gold mineralization occurred at the depths of 1.3 km to 8.1 km. Fluid inclusion analyses show that the gas phase is mainly composed of H2O and N2, with minor CO2 and O2, while the liquid phase is mainly composed of Ca2+, Na+, Cl? and SO42?. The ore-forming fluid belongs to the N2-H2O-Ca2+-Cl? system. The hydrogen and oxygen isotopic compositions of fluid inclusions show that δ18OH2O values range from 5.3‰ to 10.5‰, while [δ]D values range from -123‰ to -93‰. The ore-forming fluid came from the geothermal brine. An analysis of the fluid evolution shows that the variation of the stability of the fluid system caused by the structural transition and the boiling action played vital roles in the precipitation of gold.
Key words:  gold deposit  fluid inclusion  hydrogen and oxygen isotopes  Mawu  Gansu