一、序言橄榄石是与铬铁矿成因有关的主要造岩矿物,其中Fe~(2+)的有序—无序分布与矿物形成条件和矿物结晶后的冷却历史有关。为此,七十年代以来不少学者对橄榄石的有序—无序问题进行了探讨。Bancroft Gibbs & Smith (1968)采用X射线单晶结构分析,认为橄榄石中Fe~(2+)的分布是无序的,伯恩斯(1971)通过电子吸收光谱的测定,表明Fe~(2+)在M_2位稍有富集;(?) (1972)用穆斯鲍尔谱分析测定橄榄石的有 I. Introduction The olivine is the major rock-forming mineral associated with chromite occurrence. The order-disorder distribution of Fe ~ (2+) is related to the mineral formation conditions and the cooling history after mineral crystallization. For this reason, since the 1970s, many scholars have discussed the order-disorder of olivine. According to X-ray single crystal structure analysis, Bancroft Gibbs & Smith (1968) considered that the distribution of Fe ~ (2+) in olivine is disordered. Burns (1971) measured the electron absorption spectra and found that Fe ~ +) Is slightly enriched at M_2; (?) (1972) Determination of olivine by Mauser Bauer spectroscopy