基于Aster和Landsat8数据在青海赛什腾地区蚀变信息提取研究  

Research on alteration information extraction in Saishiteng area of Qinghai based on Aster and Landsat8 data

作　　者：王曦 程三友[1] 林海星 陈静 肖良[1] WANG Xi;CHENG Sanyou;LIN Haixing;CHEN Jing;XIAO Liang(Chang’an University,School of Earth Sciences and Resources,Xi’an,710054)

机构地区：[1]长安大学,地球科学与资源学院,西安710054

出　　处：《地质论评》2022年第1期262-280,共19页Geological Review

基　　金：中国地质调查局地质调查项目(编号:DD20190069);国家自然科学基金资助项目(编号:41872017);中央高校基本科研业务费专项资金资助项目(编号:300102279105)的成果。

摘　　要：青海赛什腾地区位于无人区,穿越条件极差,传统地质找矿勘探工作难以开展,因其植被稀少,有利于多光谱遥感数据提取矿化蚀变信息。本文以Landsat8和Aster数据为数据源,利用成像光谱法和主成分分析法对赛什腾地区进行矿化蚀变信息的提取,成像光谱法包括最小噪声变换(MNF),像元纯净指数(PPI),n维可视化端元识别(n-Dimensional Visualization)和光谱角匹配(SAM),最终获得了赛什腾地区矿物信息分布图。利用主成分分析法对Landsat8和Aster数据分别提取黄铁矿、褐铁矿等铁染蚀变矿物和绢云母等羟基蚀变矿物,通过对Aster和Landsat8两种数据提取的蚀变信息进行空间叠加分析,定量地分析对比两种数据的蚀变信息提取效果,具有提高提取蚀变信息准确性的优势。通过样品实测光谱及镜下鉴定特征验证了研究区铁染和羟基蚀变存在的真实性,并将矿化蚀变信息分布图与野外调查已知矿(化)点坐标进行叠加验证,结果显示矿(化)点坐标基本落在提取的矿化蚀变范围内,说明基于这两种遥感数据的处理方法和提取结果是可靠的,为圈定找矿靶区和扩大找矿范围提供了重要的指导意义。Objective:The Saishiteng area in Qinghai province is located in a depopulated zone with poor environment,which can be difficult to carry out geological prospecting through traditional methods.However,multi-spectral remote sensing data provide the great potential for extracting mineralization alteration information in such areas owing to abundant spectrum and continuous space information.This paper extracts remote sensing alteration anomaly information of Saishiteng mining area using Aster and Landsat8.Methods:Some minerals in the study area were identified from Aster data using imaging spectroscopy techniques such as minimum noise transform(MNF),pixel purity index(PPI),n-dimensional endmember recognition visualization(n-dimensional visualization)and spectral angle matching(SAM).For mineralization alteration information,principal component analysis(PCA)was used.Specifically,the band 1,2,3 and 4 of Aster data are used to extract the ferric contamination anomaly alteration,band3,4,6 and 7 were selected to extract the anomaly information of Al—OH altered minerals,and band 1,3,4 and 8 were used to extract the anomaly information of Mg—OH altered minerals.Meanwhile,the band 2,4,5 and 6 of Landsat8 were selected to extract ferric contamination anomaly,and band 2.5,6 and 7 were used to extract hydroxyl alteration.Results:The distribution map of mineral information in the study area was obtained through imaging spectroscopy techniques using Aster data.Through principal component analysis of Aster and Landsat8 data,the ferric contamination anomaly alteration minerals such as pyrite and hydroxyl alteration minerals such as sericite were extracted respectively,and then the distribution map of mineralization alteration information in the study area was obtained.Conclusion:Through the spatial superposition analysis of the alteration information extracted from Aster and Landsat8 data,it can not only quantitatively analyze the extraction effects,but also improve the extraction accuracy,and the ferric contamination anomaly al

关 键 词：青海赛什腾地区 ASTER Landsat8 叠加分析 矿化蚀变信息 

分 类 号：P627[天文地球—地质矿产勘探]