以ｎ维向量空间中的向量夹角为分类依据，对内蒙乌拉尔山地区５３个岩石实验室反射光谱进行相似系数聚类分析，揭示出０．４～２．５μｍ岩石谱形的总体相似性差异。结果表明，岩石的电磁波属性不同于岩石学的分类属性，提出按谱形的相似性对岩石进行归类的方法及其意义。同时分析了成像光谱技术中光谱角度填图方法的优劣及改善措施，为成像光谱图像处理方法提供了十分有意义的光谱依据 Based on the angle of the vector in the n-dimensional vector space, cluster analysis of reflectance spectra of 53 rock labs in the Urals Mountains, Inner Mongolia, revealed similar overall similarity between 0.4 and 2.5 μm rock profiles . The results show that the electromagnetic properties of rocks are different from those of petrology, and the method of classifying rocks according to their similarities is proposed. At the same time, the advantages and disadvantages of the spectral angle mapping method in imaging spectroscopy and the improvement measures are analyzed, which provides a very significant spectral basis for imaging spectral image processing methods