植被覆盖区的遥感蚀变信息提取研究及应用

发布时间：2018-05-21 02:29

本文选题：植被覆盖区 + 归一化植被指数　；参考：《中南大学》2014年硕士论文

【摘要】：摘要：植被覆盖区是遥感蚀变信息提取的难点之一,本文以贵州省北部务正道地区为研究区,使用ETM多光谱数据进行实验研究,取得了比较满意的效果。首先对遥感影像进行预处理和增强处理；其次结合基础地质资料进行遥感地质解译；再次采用“抑制中低植被覆盖区+掩膜高植被覆盖区及其他干扰因素区+主成分分析+密度分割”的方法提取了铁染蚀变异常信息和羟基蚀变异常信息；最后基于研究区地质条件和成矿规律的研究,进行遥感综合成矿预测,圈定出找矿远景区。主要取得了以下成果： 1.通过图像预处理和增强处理解决了研究区遥感影像辐射误差和几何畸变,提高了影像纹理清晰度,有利于遥感目视解译；结合研究区已有的基础地质资料,总结出各类地层与构造的影像特征,对遥感影像的地层和构造进行了解译。 2.研究区内影响蚀变信息提取的干扰因素包括植被、水系、阴影和第四系等。本文引入归一化植被指数(NDVI)确定了高植被覆盖区和中低植被覆盖区,对于中低植被覆盖区采用植被抑制算法抑制植被信息,对于高植被覆盖区和水系、阴影与第四系采用分别建立掩膜、相乘取得合膜的方法进行了去干扰操作。 3.在去除干扰因素的基础上,采用主成分分析的方法提取了研究区铁染蚀变和羟基蚀变,通过密度分割的方法分别划分为三个异常等级,制作出务正道地区铁染蚀变异常图和羟基蚀变异常图。最后将提取到的蚀变异常图斑与研究区内已知的矿体分布图进行叠加分析,发现能够很好地重合,说明提取的铁染蚀变和羟基蚀变比较好地反映了区内矿化蚀变信息。 4.结合研究区遥感地质解译成果、矿化蚀变信息提取成果、已知矿床(点)的分布情况和区域地质条件及成矿规律,进行了遥感综合成矿预测,圈定出若干个找矿远景区。
[Abstract]:Absrtact: vegetation cover area is one of the difficulties in extracting alteration information from remote sensing. In this paper, the ETM multispectral data are used as the research area in the north of Guizhou Province, and satisfactory results have been obtained. Firstly, the remote sensing image is preprocessed and enhanced, and then the remote sensing geological interpretation is combined with the basic geological data. Thirdly, the iron-stained alteration anomaly information and hydroxyl alteration anomaly information were extracted by the principal component analysis (PCA) density segmentation method of masked high vegetation cover area and other interference factors in the middle and low vegetation cover area. Finally, based on the study of geological conditions and metallogenic rules of the study area, remote sensing comprehensive metallogenic prediction is carried out to delineate the prospecting area. The following results have been achieved: 1. The radiative error and geometric distortion of the remote sensing image in the study area are solved by image preprocessing and enhancement processing, and the texture clarity of the image is improved, which is beneficial to the visual interpretation of remote sensing. The image features of various strata and structures are summarized and the strata and structures of remote sensing images are interpreted. 2. The factors affecting the extraction of alteration information in the study area include vegetation, water system, shadow and Quaternary system. In this paper, the normalized vegetation index (NDVI) is introduced to determine the high vegetation cover area and the middle and low vegetation cover area. For the middle and low vegetation cover area, the vegetation information is suppressed by vegetation suppression algorithm, and for the high vegetation cover area and the water system, the vegetation information is suppressed by vegetation suppression algorithm. The shadow and Quaternary system were operated by establishing mask and multiplying the mask to obtain the composite film. 3. On the basis of removing interference factors, iron stain alteration and hydroxyl group alteration were extracted by principal component analysis (PCA). The abnormal map of iron stain alteration and hydroxyl group alteration in Wuzhengdao area was made. Finally, by superposition analysis of the extracted alteration anomaly pattern and the known orebody distribution map in the study area, it is found that the extracted iron-stained alteration and hydroxyl alteration can well coincide with each other, indicating that the extracted iron-stained alteration and hydroxyl alteration reflect the mineralization alteration information in the area. 4. Combined with the results of remote sensing geological interpretation, the extraction of mineralization alteration information, the distribution of known deposits (points), the regional geological conditions and metallogenic rules, the comprehensive metallogenic prediction of remote sensing is carried out, and several prospecting areas are delineated.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP751

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