鄂东南矿集区程潮大型矽卡岩铁矿的矿物学特征及其地质意义

摘要

Chengchao Fe deposit is a typical skam deposit in southeastern Hubei Province. Electron microprobe analyses show that the end member of garnets in the skam stage is dominated by andradite, with minor grossular. The clinopyroxene comprises mainly diopside, with minor hedenbergite. The amphibole in the Chengchao Fe deposit mostly belongs to calcic amphiboles, such as pargasite, tremolite, actinolite and ferropargasite. The end member of garnets in the vein skam is between andradite and grossular. Vein clinopyroxene is dominated by diopside. Characteristics of skarn in Chengchao Fe deposit shows that granite may play a key role in the formation of skarns and ore bodies.%程潮铁矿是鄂东南地区典型的矽卡岩铁矿,迄今为止对其矽卡岩矿物学特征研究较少.本文以程潮铁矿主要矽卡岩矿物为研究对象,利用电子探针技术对该矿矽卡岩矿物学特征进行了研究.电子探针分析结果表明:程潮铁矿石榴石和辉石分别以钙铁榴石和透辉石为主；角闪石主要是韭闪石,其次为铁韭闪石、透闪石、阳起石.其中,早期矽卡岩阶段的石榴石和辉石分别以钙铁榴石和透辉石为主；晚期脉状矽卡岩阶段的石榴石端员组分介于钙铁榴石和钙铝榴石之间,而辉石则相对于早期矽卡岩阶段的辉石更趋近于钙铁辉石端员.通过矽卡岩矿物学特征研究表明,花岗岩对矽卡岩和矿体的形成起到了重要作用.