Extracting Alteration Anomalies Based On The ASTER And Hyperion Data In Qulong And Jiama Ore Concentration Area

The way of extracting surrounding-rock alteration with remote sensing had developed for several decades,which was gradually becoming an important method for geological mapping and prospecting.Extracting surrounding-rock alteration information provided the significant basis for calculating minertogenic rock.The ASTER data which was carried by TERRA satellite had 6 SWIR bands could clearly distinguish the clay mineral information.The Hyperion data which setting was more particular than others had applied successfully in geological mapping and surface mineral identification.Domestic and foreign scholars had done plenty of researches in extracting the information.But the researches on combination of them to extract mineral alteration were still scarcely.In this paper,we took Qulong mining area and Jiama mining area as study areas to extract mineral alteration information with ASTER and Hyperion data and integrated them together to divide metallogenic prospect area.The results were mainly achieved as followed:(1)Alteration minerals had been extracted with PCA and BR on ASTER data,including kaolinite,sericite with PCA(1,4,6,7),calcite with PCA(1,3,4,5)and PCA(2,6,7,8,9),jarosite with PCA(1,2,3,4)in Qulong mining area and calcium-garnet and diopside with PCA(1,3,4,(8+9)/2),chlorite with PCA(1,2,3,4,8,9),calcite with PCA(1,3,4,(5+8)/2)in Jiama mining area.(2)Extracting alteration minerals with Hyperion data in Qulong mining area had been carried out.Firstly,ROI was extracted with MNF,PPI,spectral matching and SAM after preprocessing which contained removing watery bands,data integration and atmospheric correction.Then,mineral alteration map was gotten by combining USGS spectral library,field spectral library and spectral response characteristic in image,and mineral alteration information had been extracted including calcium-garnet,kaolinite,sericite,malachite,jarosite,chlorite and epidote.(3)Alteration minerals extracted were basically consistent with the field geological conditions by field verification for the above-mentioned alteration minerals information.We analyzed the superimposed mineral alteration to achieve the mineral alteration map.Based on this work,dividing metallogenic area was carried out and A,B,C,D four favorable metallogenic prospect areas were identified.The research showed that combination of ASTER and Hyperion data could comprehensively extract the mineral alteration information,which would provide strong support for mineral exploration by superimposing alteration minerals extracted by the two sensors.