遥感蚀变和线性构造信息提取在西藏阿里住浪矿区一带的找矿应用

以西藏阿里住浪矿区及外围为研究对象,利用ETM+遥感数据为基本信息源,首先对遥感影像进行假彩色合成、校正、去除干扰等处理;然后对影像做滤波处理,以增强区域构造信息进行线性构造解译,运用分形几何学的原理和计盒维数法求得分维值,得出该区线性构造具有良好的统计自相似性和分形特征;再采用主成分分析法和比值法对影像进行铁染、羟基蚀变信息提取。最后综合分析线性构造分维值、遥感蚀变信息异常、区域地质、地球化学信息、已知矿床(点)信息,确定5个成矿远景区,其中Ⅰ号远景区是最有前景的异常区。

Application of Remote Sensing Technique to Extract Alteration and Linear Structure Information for Resources Prognosis in the Zhulang Periphery Mining Area,Ali,Tibet

Using ETM+ remote sensing data as the basic information sources,remote sensing geological prospecting was carried out in the Zhulang periphery mining area,Ali,Tibet.Remote sensing image was handled by synthesizing pseudocolor,correction and removing the noise.Image filtering was done in order to enhance tectonic information to explain linear structure.The fractal dimension values that were calculated by the method of fractal geometry and the box-counting dimension,and then the linear structures showed excellent statistical self-similarity and fractal characteristics in this area.Principal Component Analysis and Ratio Method were used to enhance the spectrum and space information in this area and to extract the iron-stained and hydroxy alteration information.Comprehensively analyzing fractal dimension value of linear structure,abnormality of altered information,regional geological and geochemical information,and known deposits,five metallogenetic prospective areas were determined.No.Ⅰ prospect area was considered to be one of the most promising area.