【摘要】 对大降坪黄铁矿床的Ⅲ、Ⅳ号矿体样品进行了流体包裹体的He-Ar同位素测定,3He/4He值在0.13~2.55 Ra之间,40Ar/36Ar在348~443之间,反映出成矿流体中有地幔流体的侵入,可能是深源地幔的热液沿着大降坪黄铁矿床的逆冲断层进入矿体,对矿体进行了热液改造,分化出Ⅲ号条带状矿体和Ⅳ块状矿体两个不同形态的矿石类型;矿石和围岩的稀土元素的研究结果表明,Ⅲ号矿体和近Ⅲ号矿体围岩及边坡围岩的稀土元素分配曲线基本一致,均表现为铕负异常(δEu=0.52~0.83),而Ⅳ号块状矿体及近Ⅳ号矿体围岩表现为铕正异常(δEu=1.03~14.70),可能是受到地幔热液的影响而热液蚀变改造引起的.更多还原

【Abstract】 He-Ar isotopes of fluid inclusions in six samples of the Dajiangping pyrite orebodies III and IV were measured.The（）³He/⁴He values ranged from 0.13 to 2.55 Ra and the（）⁴⁰Ar/³⁶Ar ratios ranged from 348 to 443.The data indicate that mantle-derived fluids contributed to the ore-forming fluids.This study suggests the hot fluids from the deep mantle intruded into the ore body along the thrust fault,hydrothermed the orebody,and differentiated it into banded orebody III and massive orebody IV.Rare earth elements of the ores and wall rocks were also measured in this study.The REE patterns of orebody III and the country rocks close to orebody III are essentially consistent,showing negative Eu anomailes（δEu=0.52⁰.83）,while orebody IV and the country rocks close to orebody IV show positive Eu anomailes（δEu=1.03¹4.70）.The reason may be owed to the hydrothermal alteration by the intrusion of mantle fluid.更多还原