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封面故事：辽宁瓦房店金伯利岩带50号岩管的金刚石采坑。中国东部金刚石产于辽宁瓦房店—山东蒙阴的金伯利岩带和湖南宁乡—贵州镇远的钾镁煌斑岩带等深部来源的岩浆岩中。该50号岩管采坑出产了中国量产最大、品质最优的金刚石。研究表明, 深部来源的含金刚石的金伯利岩等岩浆, 可将浅部地壳的物质烘烤融化, 形成碱性花岗岩和碱性流纹岩; 而直接快速上升到地表的金伯利岩则可形成含金刚石的金伯利岩管。显微照片中被磨蚀的椭圆状角砾, 指示金伯利岩浆上升至浅部的过程极为迅速, 从而使金刚石不易溶蚀而赋存于母岩中。这项由国家地质实验测试中心曾普胜教授主持的研究成果, 详见本专辑721-748页。（图片提供：曾普胜）
Cover Story：The Diamond open pit mine of the No. 50 pipe in the Wafangdian Kimberlite Belt, Liaoning Province. Diamonds in eastern China are produced in the kimberlite belts of Wafangdian (in Liaoning) and Mengyin (in Shandong) and the lamproite belts of Ningxiang (in Hunan) and Zhenyuan (in Guizhou). The open pit mine of the No. 50 pipe in Wafangdian Kimberlite Belt produces the largest quantity of diamonds that exhibit the best quality in China. The results show that the deep magma, including dia-mondiferous kimberlitic magma, can melt the material in the shallow part of the crust to produce alkaline granite and alkaline rhyolite; however, the kimberlitic magma that rises directly and rapidly to the surface can form diamondiferous kimberlite pipes. The abrasive elliptic breccias in the photomicrograph indicates that the kimberlitic magma rises to the surface rapidly and ensures that the diamond is retained in the parent rocks. The research achievement was led by Professor ZENG Pu-sheng, National Research Center for Geoanalysis, CAGS. For details, see pp. 721-748 of this special issue. (Photo by ZENG Pu-sheng)
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