Alteration And Application Based On Hyperion In Lop Nor Area

Utilizing satellite borne Hyperion remote sensing data for prospecting is mainly by using image processing technology to dig out the relevant alteration information,or likely to delineate or forecast area and the range of mineralization.It is a perfect combination of remote sensing technology and geology.The mentioned study area is located in the eastern town of Lop Nor in Ruoqiang County,because of the advantages of the degree of exposed rock,cutting depth,characteristics of vegetation coverage and less large deposits,where is a good demonstration area for prospecting by satellite borne Hyperion remote sensing data.The main content of this paper is divided into three parts: extracting iron stain and hydroxyl alteration information based on principal component analysis(PCA)and ratio method(Band Ratio);gaining metallogenic map of study area by spectral angle mapping method(SAM);comparing themetallogenic map of study area to the geological map of Iron staining,hydroxyl alteration information and making some analysis.Firstly,the history,geography and geological background of the study area in Lop Nor are analyzed,and the strata,structure,minerals and alteration of the study area are summarized in the paper.We roughly determine the type of the altered minerals.Then it extracts mineral alteration anomaly information from Hyperion images in the study area according to the principleof rocks and minerals mineralized and altered under the action of geological hydrothermal fluids and the spectral characteristics of the clay minerals,iron minerals and carbonate mineral ions produced by mineral alteration.On the basis,Hyperion L1 R the original image has been preconditioned,such as calibration and water vapor effect band removal,absolute blessing conversion,bad line restoration,fringe removal,Smile effect repair,atmospheric correction and geometric correction etc.After that,alteration anomalies of iron stained minerals and hydroxyl minerals are extracted from Hyperion image by principal component analysis and ratio method.To obtain the mineral distribution map in the study areashould performed spectral angle mapping(SAM).After all,five types of Endmember mineral have been found.Then after spectral angle mapping(SAM)is used to analyze the mineral assemblage,Sericite,Hematite,Feldspar,Phlogopite and Tourmaline are comfirmed to be the minerals to form the metallogenic information map in the study area finally.The study area has repeatedly appeared large or super large deposits,according to the geological condition,referring to the relevant geological literature,especially the study of metallogenic zone distribution,combining the extracted alteration information and metallogenic mapping in this paper,we can find that the extracted iron mineral,hydroxyl mineral and metallogenic mapping information have a good anastomosis with the stratigraphic structure and mines of the study area.It really makes sense to predict alteration information and metallogenic mapping by using Hyperion image data,and can effectively predict the favorable metallogenic target in other regions.