山东蒙阴金刚石的“似玛瑙状”生长结构及氮、氢杂质分布的不均一性

Agate-like Structure and Heterogeneities of Nitrogen and Hydrogen Impurities of Diamond in Mengyin, China

阴极发光(CL)技术可揭示金刚石生长结构、阶段和过程。利用该技术首次发现蒙阴金刚石中罕见的“似玛瑙状”生长结构,并分析了该典型结构的特征和生长机制。该样品定向切片的傅立叶变换红外光谱(FTIR)微区分析表明,氮、氢杂质分布不均一,从生长中心至边缘,总氮含量和B中心百分数逐渐降低,但变化幅度较小;氢浓度呈不规则振荡,边缘区最高。该生长结构和杂质不均一特点揭示了金刚石生长过程中熔/流体的参与作用和生长条件、环境的复杂性。

The growth structure, period and process of diamond can be revealed by the cathodluminescence （CL） technique. The rare agate-like structure of diamond is first discovered in Mengyin area, Shandong Province, China and its characteristics and genetic mechanism are discussed. The FTIR in-situ analysis of the oriented plate of the diamond shows that there exist heterogeneities of N and H impurities. The total contents of N and percentage of B defects decrease gradually, and the H contents fluctuate irregularly from central to periphery of the diamond. The growth structure and heterogeneities of the impurities indicate participation of melts/fluids and the complexities in growth processes and environments in upper mantle.