The contents of the major and trace elements in 3 samples of the claystone with different types and textures, from the coal measures of the Taiyuan and Shanxi Formations of Permo-Carboniferous of Xiaoyu coal mine of Datong, Shanxi province, are detected by the methods of chemical analysis and INAA respectively. By the contrast analysis of the elements with geochemical tracer and their ratio, three samples, on geochemistry as a whole, are not of the typical characteristics of sedimentogenic mudstone, and could be formed in situ from the alteration of acidic or alkali-acidic ash (fallout or water-carried) under the conditions of the shallower water and weak oxydation on the surface. The alteration of the claystone is stronger on the whole, and it causes much loss of the unstable elements, even some of more stable elements, such as ferromolybdenum and manganese. The environments, medium conditions and original matter and its size at the ash alteration, as well as the clay minerals of the clay rocks are the major reason of the differences on the types and element contents of the claystones.%采用化学法和中子活化(INAA)法,对山西大同小峪煤矿山西组和太原组的3件不同粘土岩样品的8种常量元素(氧化物)和33种微量元素含量进行了测定.通过对具有示踪意义的元素及其比值的对比分析表明,3个样品总体上均不具有典型的沉积岩特征,应该是由酸性或酸性偏碱性火山物质(降落的或陆源搬运的)在地表覆水较浅的弱氧化条件下经原地淋滤、蚀变形成的.岩石总体蚀变程度较高,不稳定或较不稳定的元素大量流失,甚至一些较稳定的元素(如高岭岩中的铁、锰)也明显流失.蚀变环境及介质条件、成岩原始物质组成及其粒度大小以及粘土物质组成是造成粘土岩类型及其不同类型间元素含量差异的主要原因.
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