质子微束对磷灰石中稀土元素的研究

PROTON MICROPROBE STUDY OF RARE EARTH ELEMENTS IN APATITE

应用质子激发X射线(PIXE)和质子激发γ射线(PIGE),分析了取自不同地质环境的14个磷灰石样品中的主体元素和替代元素。磷灰石中稀土元素含量对于球粒状陨石的标绘表明,绝大多数磷灰石样品对于轻稀土元素有富集现象。磷灰石本身并不表现出特别富集轻稀土的特性。因此这种元素组份的分布可以成为磷灰石结晶过程所处的地质学环境中化学和物理条件的指证。

A combination of proton microprobe induced X-ray emission and γ-ray emission are used to determine the major- and minor-element contents of fourteen apatite samples from various geologic environments. The chondrite-normalized distribution of the rare earth element (REE) shows light REE enrichment for the majority of samples. The apatite structure may not concentrate LREEs relative to the HREEs. The actual REE distribution in a particular apatite is often indicative of the chemical and physical conditions under which it formed.