中文摘要：

南极拉斯曼丘陵长英质片麻岩中的粗粒夕线石可能有内部出溶现象,出溶形成的矿物有磁铁矿、钛铁矿-赤铁矿和石英出溶矿物条纹,并有少量的斜方辉石。电子探针成分分析表明,本区夕线石高温结晶时不仅有Fe^3＋,可能还有Fe^2＋、Mg^2＋和Ti^4＋的替换,铁氧化物质量分数可高达2.9%;随着温度的不断降低,固溶体互溶度也不断减小,大部分微量组分从夕线石中析出形成出溶结构,而且低温变体中稳定的替换元素以Fe^3＋为主。铁组分的类质同像替换对物理化学计算和夕线石矿化环境均有所影响,对夕线石晶胞参数a的影响很小,而对b,尤其对c的影响较大,与前人的结论有所不同。

英文摘要：

The exsolution assemblage of sillimanite from quartzofeldspathic gneiss in the Larsemann Hills of East Antarctica consists of magnetite, ilmenite-hematite and quartz exsolution laminae and minor orthopyroxene. A compositional analysis shows that the sillimanite primarily crystallized at high temperature has not only Fe^3 ＋ but also Fe^2＋ , Mg^2＋ and Ti^4＋ substitutes. Iron oxides can be as high as 2.9%. With the decreasing temperature, tion in sillimanite has an insignificant effect on a but a substantial effect on b, especially on c values of the crystal cell lattice. These results are to some extent contradictory to the previous conclusions.