Extraction method of PCA for alteration mineral mapping, using Landsat TM data in northwestern Junggar basin

摘要

Wall rock alteration is an important indication of mineralization. On the basis of analyzing spectrum characteristic of Landsat Thematic Mapper (TM) image data, the rock ore spectrum characteristic and the theory of extracting information from remote sensing, this paper utilized Principal Component Analysis (PCA) to analyses and mapping efficiency of alteration information extracting. Study area is located in the North West periphery of Junggar Basin, China. PCA was carried out on six bands of Landsat TM data and the relevant principal components were chosen to obtain images that show alternation minerals. The results showed that PCA technique can be used as a very reliable method for enhancing the areas with alteration as a fast, effective and cheap tool for exploration of mineralization information in the northwestern Junggar basin.