Remote Sensing Image Digital Processing And Geological Interpretation In Shiquanhe Area,Tibet

Multi-source remote sensing image fusion,as an important means of comprehensive processing and analysis of data in the field of remote sensing,can make up for the shortcomings of low-spectral resolution or low spatial resolution of single remote sensing data,and has the advantages of complementarity,accuracy and usability and has been well used in various fields.Taking the Shiquanhe area in Tibet as an example,which is rich in strata and complex in structure,this paper puts emphasis on the combination of method experiment and interpretation verification.It has carried out exploratory research on remote sensing image digital processing and geological interpretation.In this paper,the geological overview of the study area are summarized,and multi-source remote sensing fusion data is selected and image fusion processing is performed.By comparing and analyzing the characteristics and advantages of the fusion methods,based on the fusion image quality evaluation,the best fusion image is screened,and the remote sensing geological interpretation and field verification of the study area are completed.The main research contents and results are as follows:(1)By analyzing the features of Landsat 8 OLI remote sensing image and ZY-102 C remote sensing image,the digital image processing technology is used to perform radiation calibration,atmospheric correction and cropping on Landsat 8 OLI data;The ZY-1 02 C data is processed by orthorectification,image mosaic and cropping,and the spatial registration of the image to be fused is completed.The multi-spectral remote sensing image map and the high spatial resolution image map of the study area are respectively generated.(2)Through multi-source remote sensing image fusion methods,including wavelet transform image fusion method based on band analysis(Wavelet-SB fusion method),and HPF fusion method,Brovey fusion method,Gram-Schmidt fusion method,PC fusion method,HSV fusion method.The method of fusion of multi-source remote sensing images in the study area is carried out by the method of 6pairs of fusion methods.It is preliminarily believed that the Wavelet-SB fusion image has the superiority of maintaining multi-spectral information and improving spatial detail information.(3)A fusion image quality evaluation system combining subjective evaluation and objective evaluation is established.The peak signal-to-noise ratio,mutual information,mean square error and variance are used to measure the image correlation degree;standard deviation,average value and entropy are used to measureinformation richness;average gradients and other indicators for measuring the texture definition,a total of 8 indicators.The quality of six fusion images such as Wavelet-SB fusion image,HPF fusion image,Brovey fusion image,Gram-Schmidt fusion image,PCA fusion image and HSV fusion image conduct an evaluation.The results show that the fusion quality of Wavelet-SB fusion images is higher than that of the other five fusion images.(4)The Wavelet-SB fusion image was used to carry out the geological interpretation of the study area.Through the establishment of remote sensing geological interpretation marks in the study area,the interpretation of geological information such as strata,magmatic rocks and fault structures in the study area was completed.Through field verification,the boundaries of the surrounding units are clear,consistent with the actual geological conditions,and the structural traces are clear,accurately reflecting the geological structure of the study area.