Research On Remote Sensing Mineralization And Alteration Information Extraction In Meng Mountain Area Of Jiangxi

The Meng Mountain region is located in the central and western Jiangxi Province,between the Lower Yangtze paraplatform and the South China fold system,and belongs to the central part of the western section of the Pingle Depression.The geological conditions in this region are superior,and there are many typical ore deposits,such as the Taizibi tin polymetallic deposit,the Shizhushan wollastonite deposit,and the Zhutoushan tungsten polymetallic deposit,which all have good prospecting potential.Due to the fact that most of the area is mountainous and hilly,it is difficult to carry out traditional geological prospecting.Mineral prospecting based on remote sensing technology can effectively solve the problems of low efficiency and high difficulty in alteration extraction.This paper first performs atmospheric correction,terrain correction,image fusion,and image clipping preprocessing on ETM+ images,and then uses methods such as band ratio method,standard principal component analysis,feature vector principal component analysis,directional principal component analysis,and secondary principal component analysis to extract iron contamination and argillization mineralization alteration information in the Meng Mountain area.The results show that this extraction method is very suitable for research areas with high vegetation coverage characteristics,can effectively reduce interference from vegetation information,and improve the accuracy of alteration extraction.Through the analysis of remote sensing mineralization and alteration results in this region,the distribution characteristics of mineralization and alteration have been successfully identified,providing strong support for the division of the metallogenic prospective area in this region.The main understanding obtained in the paper is as follows:(1)Among the results obtained by five alteration extraction methods,including band ratio method,standard principal component analysis method,feature vector principal component analysis method,directional principal component analysis method,and secondary principal component analysis method,secondary principal component analysis method and standard principal component analysis method have extracted a better alteration range;The feature vector principal component analysis showed a strong iron stain alteration feature;The results of band ratio method and directional principal component analysis method for alteration extraction are poor.After comparison,the secondary principal component analysis method performs the best in extracting alteration information and has the most accurate effect.(2)The color composite images obtained by standard principal component analysis,feature vector principal component analysis,and secondary principal component analysis showed that argillization and ferritization occurred in a large area in the study area.The regional alteration distribution of the Indosinian intrusive rocks in the Meng Mountain rock mass is the densest and strongest;Secondly,strong iron contaminated alteration information was extracted from the Qibaoshan in the north,Dongmen rock mass in the east,and Tieshan and Tiekeng areas in the south;Obvious alteration information has also been extracted from the mountain slopes in the west,Chengwu and Huagu mountain areas in the east.The above mineral alteration distribution indicates that the study area has a relatively high prospecting space and is worth increasing geological exploration efforts.(3)By superposing and comparing the extracted mineralization and alteration information with existing geological data,geochemical anomaly data,and field survey results,a total of eight mineralization prospect areas were divided in the study area,including one Class I mineralization prospect area,four Class II mineralization prospect areas,and three Class III mineralization prospect areas,and a distribution map of mineralization prospect areas was prepared.