关键词: 遥感, 光谱分析, 纹理分析, 长白山天池

Abstract: The terrain near the Changbaishan Tianchi volcano caldera is complex and highly covered with vegetation,so it is difficult to determine the precise spatial distribution extent of the volcanic eruptive products only using the geological or visible remote sensing technology.In this paper,based on the analysis of spectrum and texture information from the IKONOS image of the study area,eight types of training samples are selected and the spectral angle technology(SAM)is applied to perform classification. These eight types of surface include water body,shadow,thick pumice,thin pumice,trachyte, soil,vegetation and forest.The primary results of such classification are not satisfactory through confusion matrix evaluation,which may be due to a serious loss of spectrum information in the synthesizing process.However,the texture information of the image is abundant.Therefore,we introduce the texture analysis of the ENVI probability matrix method which takes advantage of dissimilarity texture feature to establish the symbol of texture interpretation.Our final results indicate that the accuracy of classification may be greatly improved by using the combination of spectrum and texture analysis. Taking the widely distributed pumice as an example of classification,we obtain the information of both the extent and the relative thickness distribution of pumice near the Tianchi caldera region.In the future, more work should be concentrated on the field investigation to confirm the terrain features of eight types which are obtained from the satellite image interpretation before that remote sensing technology will truly become one of the useful tools for geological mapping and volcanic hazards evaluation.

Key words: remote sensing, spectrum analysis, texture analysis, Changbaishan Tianchi volcano