Enhancement And Extraction Of Lithology In Metamorphic Rocks Zone:Based On Collaborative Image

Tianshan-Beishan metallogenic belt is one of the three important metallogenic belts in western China, with a strong regional metamorphism, favorable metallogenic conditions, and metamorphic zone is also widely distributed. The metamorphic zone tend to be concentrated within the metallogenic belt with a lot of copper, gold and other metal deposits. Since these metamorphic area is located in the eastern region of Xinjiang, northwestern Gansu and western Inner Mongolia, the Gobi desert area with bad weather, sparse vegetation, and sparsely populated, makes field work under very difficult conditions. However, the arid climate with low vegetation coverage, are very beneficial for remote sensing technology play to their strengths in the region.This paper analyzes the typical spectral characteristics of lithology in Qingger, Yamansu, White beaches and other metamorphic zones, based on the combination of the bands of different lithologic characteristic in metamorphic zone.The collaborative data comes from the WorldView-2 high-spatial resolution image and ASTER Medium resolution multispectral images. This study try to use the ratio of the characteristic bands of this collaborative data in metamorphic zone to complete mafic veins, gneiss, marble, quartzite and quartz schist corresponding enhancement processing.According to the bands of the typical lithology in metamorphic zone, the collaborative data main covers the spectral data in visible-near infrared, short infrared range. Collaborative data well inherited the high resolution advantages of the WorldView-2 data, and make up for the defects of WorldView-2 with no short-wave infrared and thermal infrared bands. With respect to the ASTER image, collaborative data not only enrich its spectral information in visible-near infrared spectral range, but also improve the spatial resolution of the data in its own short-wave infrared, thermal infrared range.In the Qingger area, Firstly, this study uses the differences of the spectral characteristics data of mafic dikes and their surrounding rocks, by band4/band8 of the collaborative data, the study area can be enhanced mafic dikes from the surrounding rock; Secondly, this study uses the differences of the spectral characteristics data of the plagioclase, K-feldspar spectral curve, by band5/band3 of the collaborative data, the K-feldspar granitic gneiss and granitic gneiss plagioclase can be enhanced out in this study area; Thirdly, with the the differences of the spectral characteristics data of marble, quartzite, quartz schist, this study chose band14/bandl3 of the collaborative data, and can be easily distinguish the quartzite, quartz schist from the surrounding rocks in marble rock. Finally, the ratio of these three factors typical lithology, were used to make false color composition in the region. The enhance image in this study area had been a great help to recognition and interpretation of lithology, and enhance the capability of the regional metamorphic Solutions translation in the overall image level in metamorphic zones.