橄榄石位错构造的扫描电子显微镜研究

A Study of Dislocations in Olivine Using a Scanning Electron Microscope

利用扫描电镜的背散射电子图象(BEI)对玄武岩及金伯利岩所含幔源包体中橄榄石的缀饰位错进行了研究。实验结果表明,位错类型和颗粒边界图象清晰,又便于观察。这种观察位错的方法其分辨率比光学显微镜观察结果约高一个数量级。背散射电子图象位错方法特别适用于研究天然的和实验变形橄榄石的高位错密度和密集型边界,对于确定显微构造的定量参数也十分有利。

Decorated disiocations in olivine from the upper mantle xenoliths have been examined with a scanning electron microscope (SEM) using a backscattered electron image (BEI). Experimental results indicate that dislocation patterns and grain boundaries are a clear bright image and easily observable. The resolution of this method for dislocation observation is about an order of magnitude better than that of optical microscopic observation. The method of dislocation using a backscattered electron image is especially useful in the study of high dislocation density and dense dislocation boundary in naturally and experimentally deformed olivine and in the determination of quantitative parameters of microstructures.