西藏中南部各类花岗岩中磁铁矿标型特征的研究

磁铁矿是最常见的贯通矿物之一,各种地质体中均可见到。不同成因的磁铁矿,其化学成分,内部结构和物理性质等是有差异的。因此,根据磁铁矿的某些特征来探讨其岩体成因是有一定意义的。

Study of Typomorphic Characteristics of Magnetite in Various Types of Granites of Central-South :Kizang (Tibet)

In studying the characteristics of magnetite and other accessory minerals ''in various granitic rocks of Central-South Xizang, the author found that magi betites from different types of granites formed under different geological con- dlitions and of different ages have distinctly different characteristic features. The content and chemical composition of magnetite as well as the mineral assemblage and rare-earth pattern in the granite all reflect either the man- tle or crustal origin of the rock. It is concluded that the granodiorite in the Gangdise belt is characterized by mantle origin and the muscovite-biotite granite and tourmaline granite in Nielamu district are of crustal origin.