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笔者近几年在苏北古老片麻岩,花岗斑岩,石英斑岩,石英脉,硅化角砾岩,蚀变碎裂岩及第四纪砂砾层中,均发现了一种黑色具磁性的球粒。经形貌特征分析,结构构造鉴定及电镜扫描,x—射线纷晶分析,电子探针,中子活化分析,证明这种磁性球是铁质宇宙尘。但其元素丰度与铁陨石有某些差异。如Ni,Co含量低,贫缺贵金属Os,Ir而富Cu,As、Sb、W等元素。所以推测这种宇宙尘并非是铁陨石消融产物,而可能是流星体(慧星)的消融产物。文中从宇宙尘该区多种岩石中都有产出,探讨了宇宙尘参与地壳物质演化过程,以及演化后宇宙在种类上,数量上,成分上的变化。同时对宇宙尘的降落背景及在解决岩石成因上做了探讨。对其研究无疑是重要的。
In recent years, the authors have found a black magnetism in the ancient northern gneiss, granite porphyry, quartz porphyry, quartz veins, silicified breccia, altered cataclastic rock and Quaternary gravel layer Of the pellets. The morphological analysis, structural identification and scanning electron microscopy, x-ray quantum crystal analysis, electron probe, neutron activation analysis showed that this magnetic ball is iron cosmic dust. However, there are some differences between the element abundances and the iron meteorites. Such as Ni, Co content is low, the lack of precious metals Os, Ir rich Cu, As, Sb, W and other elements. Therefore, it is speculated that this cosmic dust is not an ablation product of iron meteorites, but may be an ablation product of a meteoroid (comet). In this paper, we have produced a great deal of rocks from cosmic dust in this area, and discussed the evolution of cosmic dust involved in the crustal material, as well as the changes in the types, quantities and compositions of cosmic dust. At the same time, it discusses the background of the cosmic dustfall and the origin of the rock. Its research is undoubtedly important.