摘要
成矿带内分布二叠系火山—沉积岩系地层,其中富含Sn、W、Ph、Zn、Cu成矿元素。燕山期成矿钾长花岗岩分异良好,以富Si、K>Na,贫Ca、Fe、Mg,同时富含W、Sn、Pb、Zn、Cu、Ag等成矿元素,且含量愈高,方差愈大,δEU愈小,对成矿愈有利。地球化学和同位素、稀土元素资料均表明成矿花岗岩浆兼具S型和I型特点,可能成矿岩浆系慢源岩浆同化混熔二叠系地层所形成。
Permian sedimentarry rocks of high backgroud content of metailogenetic eie-ments(Sn, W, Pb, Zn, Ag)are widely distributed all over the tin-polymetallogenetic zone of Huangang. Ganzhuermiao, north Chifeng. Yanshanian granites related to tin-po lymetalliza-tion intruded paralled to the fold axial trend of the sedimentary strata.K-feldspar granites resalting the mineralization were enriched by SiO2 ,K2Oand Na2O and depleted in CaO,FeO,MgO and were evidently differetiated.The metallogenetic element contents of the K-feldspar granites are much higher then those of other granites in this area.Chondrite-normalized REE patterns V shaped incline to right and show large negative Eu anomalies.Geochemical and isotopic study indicates the granites are characterized by dual features of both I-type and S-type granites End believed to be the result of assimiliation of Permian sedimentary rocks in a mantle derived magma.
关键词
内蒙
成矿作用
花岗岩
岩浆
metallogensis, k-feldspar granite assimilate
