Method Research Of World View-3 Data On Data Processing And Alteration Information Extraction

The study area is located on the western part of Beishan orogenic belt in Xinjiang Province,with complicated strata,structure and magmatic rocks,which provide good geological background conditions for the form of the minerals like iron,copper,gold,nickel,etc.Therefore,the Beishan area has good ore prospects.WorldView-3 is a multispectral commercial satellite with abundant bands,high radiation resolution and the highest spatial resolution currently on the market.It has a wealth of short wave infrared information and geological application prospect,especially in the extraction of alteration information.However,using WorldView-3data for the research of extracting alteration information is relatively few at home and abroad.This paper proposed some remote sensing alteration information extraction models of WorldView-3 data on the basis of the processing of WorldView-3 data,and also validated and analysis the extraction results.The main achievements are as follows:(1)On the basis of some experiments,this paper preliminarily determined the processing methods that are applicable to WorldView-3 data.Given the purpose of extracting alteration information in this paper,the main preprocessing steps are radiation calibration and atmospheric correction,and finally,formula L=(?) is used to calibrate the radiation and FLAASH model for atmospheric correction.(2)Based on the spectral analysis of the alteration minerals,we selected appropriate bands for combinations and applied the Principal Component Analysis(PCA)and mineral index models to extract alteration information using WorldView-3data.According to the geological background of the study area,this paper put forward5 principal component analysis models(Al-OH,Mg-OH,Fe-OH,iron stain and carbonate)and 10 mineral index(the index of hydroxy,Al-OH,Mg-OH,Fe-OH,iron stain,carbonate,kaolinite,calcite,siderite and jarosite),and then extracted the corresponding alteration information.(3)The alteration information results extracted by the models proposed in this paper are mainly analyzed by four methods: (1) Comparing the extracting results of different methods;(2) Comparing the extracting results of WorldView-3 data with the results of ASTER data;(3) With the analysis of field validation;(4) Analysizing the result combined with the regional tectonic-lithologic remote sensing interpretation chart of the study area.Analysis results show that for the similar alteration,different methods and data have similar extraction results.In the meanwhile,partial alteration extraction results also get field validation,and are consistent with the geological background.In general,the overall extraction effect is good,which reflects that the principal component analysis models and mineral index models presented by this paper based on WorldView-3 data have a certain accuracy.