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0．13～2．55Ra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（8Eu=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（8Eu=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．
He-Ar isotopes of fluid inclusions in six measured. The ^3 He/^4 He values ranged from 0. 13 to data indicate that mantle-derived fluids contributed to samples of the Dajiangping pyrite orebodies Ⅲ and IV were 2. 55 Ra and the ^40Ar/^36Ar ratios ranged from 348 to 443. The 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 （δgu=0.52-0. 83）, while orebody Ⅳ and the country rocks close to orebody IV show positive Eu anomailes（δEu= 1.03- 14. 70）. The reason may be owed to the hydrothermal alteration by the intrusion of mantle fluid.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2006年第6期611-620,共10页
Journal of Nanjing University（Natural Science）
基金
国家自然科学基金(40221301
40572056)
教育部高等学校博士点基金(20030284031)
