Information of ASTER VNIR-SWIR bands was processed to extract lithologic data of Aletashi area which is located in the western part of the West Kunlun orogenic belt where rock samples are absent. First, applying of the optimal index factor (IOIF) operation on the ASTER VNIR-SWIR reflectance data, obtained the optimal bands, the composition Band 7-Band 4-Band 3, then using the method of false color combination on these three bands to identify minor lithologic units in the study area. In order to reduce the information redundancy in the high correlated bands, and to integrate the information, we applied principal component transformation and color combination of principal components methodology on ASTER VNIR-SWIR reflectance data, and identified the main lithologic units such as Silurian stratigraphies, paleo-proterozoic Bulunkuole stratigraphies, adamellite, tonalite, and small-sized geological bodies such as the thermal contact metamorphic aureoles, small stocks and lithological boundaries in the study area effectively. The limited geological data suggest that the results are credible, and thus, we can accomplish the lithologic mapping with proper amount of field survey, so as to supply advanced information for geological mapping.%以西昆仑造山带西段阿勒塔什地区为例,在缺少地表各岩石单元样品的情况下,对ASTER VNIR-SWIR波段反射率数据进行处理,提取岩性信息.首先对VNIR-SWIR多波段反射率数据进行最佳指数因子(IOIF)运算,得出最佳波段组合Band7-Band4-Band3,从其假彩色合成图像上只能识别少量岩性单元；为了减少高相关性波段之间的信息冗余度、并对波段信息进行集成,后对ASTER VNIR-SWIR波段反射率数据采用主成分变换并进行彩色合成,该图像能详细划分研究区多种岩性单元,如元古宙岩层、志留纪岩层、二长花岗岩岩体和英云闪长岩岩体,以及微观地质信息,如侵入岩热接触变质带、小型岩株和岩性界线.对比已有少量地质资料,认为提取结果可靠,为野外地质制图工作能提供超前信息.
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