摘要
辽宁弓长岭铁矿床二矿区的矿石可分为较富和较贫两种类型,其中富矿的边部分布有大量的类矽卡岩,包括石榴石岩、绿泥石岩、含石榴石绿泥石岩、含磁铁矿阳起石岩等,说明富矿的形成与热液活动有关。类矽卡岩及两类矿石的微量元素相对原始地幔富集大离子亲石元素和高场强元素,但Sr、Hf相对亏损;稀土元素特征表现为总量较低,具有相似的PAAS稀土配分模式,为轻稀土元素相对亏损的左倾型,具有明显的Eu正异常和弱Ce负异常。从较贫铁矿石、较富铁矿石到类矽卡岩稀土元素总量呈逐渐上升趋势,结合野外地质特征,说明较富铁矿石和类矽卡岩在继承了较贫铁矿石的稀土配分模式的基础上可能又叠加了热液中的稀土元素地球化学特征,因此弓长岭铁矿床出露的类矽卡岩、较富铁矿石可能是由热液交代改造原始沉积的较贫铁矿石形成的。
No.2diggings of the Gongchangling iron deposit distributed two types of the richer-ores and poorerores.Around the rich iron body distributed a large number of skarnoid,including garnet-rock、chlorinerock、garnet-chlorine-rock、magnetite-actinolite-rock.The formation of skarniod and richer-ores related to the hydrothermal activity.The trace elements of skarnoid and ores show relatively enriched HFSE and LILE,but relatively depleted Sr and Hf;the skarnoid、poor-ores and rich-ores have similar PAASnormalized REE patterns,rightist distribution patterns of relative loss LREE with a obvious Eu positive anomaly and weak Ce negative anomaly,REE and Eu positive anomaly increase regularly from poorerores、richer-ores to skarnoid,which indicate richer-ores and skarnoid had inherited REE patterns of poorerores,and superimposing REE geochemical characteristics of hydrothermal fluid.Combined with field geological features,we favor that the skarnoid and rich-ores might be formed by the hydrothermal transformation of poor-ores from No.2diggings of the Gongchangling iron deposit.
出处
《地质学报》
EI
CAS
CSCD
北大核心
2014年第10期1889-1903,共15页
Acta Geologica Sinica
基金
“973”项目之课题“沉积变质型铁矿成矿环境与富矿形成机制”(编号2012CB416801)
国土资源部公益性行业科研专项经费项目之课题“辽宁弓长岭沉积变质型铁矿科学基地研究”(编号200911007-15)
“我国北方沉积变质型岩浆型铁矿富矿成矿地质作用研究”项目(编号201111002)
地质矿产调查评价项目“辽冀地区沉积变质型铁矿控矿因素和勘查技术方法组合优选”(编号1212011120988)联合资助的成果
