试用主分量分析方法提取澜沧江兰坪地区铜矿化蚀变遥感信息

通过图像影像特征分析,并经地面调查证实,澜沧江兰坪地区铜矿化蚀变与围岩存在反射波谱特性差异,即在TM5(近红外)波段(1.55μm-1.75μm)蚀变岩呈高反射率。以此为依据,进行了提取与铜矿化蚀变相关的TM遥感信息的计算机图像处理技术方法研究。实践证明,该区主分量分析处理图像效果最佳。图像上显示的色调异常,通过与红土涧矿区地质勘查资料对比和根据兰坪地区图像上典型地物样区色调理论分析,评价了遥感异常的地质意义。由于图像预处理(几何校正、亮度拉伸、多元统计,最佳波段组合选择等)是针对澜沧江兰坪全区的特征进行的,故处理方法在全区内均有一定适用性。本文结合公式2、图4、表4、封二彩片5等实际材料较详细地介绍了有关提取铜矿化蚀变遥感色调异常信息的方法技术。

A STUDY FOR EXTRACTION OF THE CU-MINERALIZATION- LTERATION INFORMATION IN LANCANGJIANGLANPING REGION BY PRINCIPLE COMPONENT ANALYSIS OF REMOTE SENSING DATA

It was confirmed by sampling in site and on image, that there are anomalistic characteristics of spectra (high reflection in NIR TM51.55μm-1.75μm) in the Lancangjiang Lanping Region. It provides the scientific basis for the experimental research of image processing techniques for extraction of the TM RSinformation, related to the Cu-mineralization and alteration. The best results were get by the principle component analysis. The geologic nature of the anomalies was evaluated by comparison with the geological work in Hong to jian area and by the theoretical calculation of the image sampling. Becuse of the fact,that the image preprocessing (the geometric restoration, the brightness scaling, the multivariate statistics, the optimized choice of TMchannels etc.) was accomplished for the whole region uniformly. So it is reasonable to consider, that the obtained processing technique is also applicable for the whole region. And this paper describes it with full and accurate table(4), formulse(2), graphics(4) and colour images(5).