Study On Interpretation Of Complex Geological Body Based On Synergy Of Multi-sources Satellite Remote Sensing Data

Geological bodies are geological products formed by geological processes and has the specialization of mineralization.Identification of ore-forming geological bodies is of great significance to guide ore prospecting.In the process of geological body formation,it often goes through a complex geological process,resulting in complex composition and structure.At the same time,due to the difficult and dangerous surface conditions in some parts of central and western China,it is impossible to carry out on-site direct investigation,which limits the surface exploration of complex geological bodies.Remote sensing technology has become an indispensable means of geological work,and it has also promoted the study of high-precision and quantitative interpretation of complex geological bodies.Previous studies have shown that higher spectral resolution can more accurately represent the differences of surface lithology,while higher spatial resolution can more finely express the boundaries between geological bodies.Due to the limitations of current satellite remote sensing technology,there is often a contradiction among spatial resolution and spectral resolution,which limits the application of remote sensing in the interpretation of complex geological bodies to a great extent.At the same time,due to the limitation of the number of spectral bands,the data of a single sensor are often unable to cover the characteristic bands of a variety of characteristic minerals.Therefore,it is worth exploring and studying to make full use of the complementary advantages of existing multi-source remote sensing data in spatial and spectrum as well as the different spectral band setting to alleviate this contradiction under the existing technical level.This study aims at the interpretation of complex geological bodies and proposed a synergistic idea of multi-source satellite remote sensing data.Focusing on the related problems in spectral and spatial synergy of multi-source remote sensing data,the synergistic application framework and synergistic processing method of multi-source remote sensing data are studied.Through the construction of synergistic image datasets,comprehensive utilization of higher spatial resolution image and higher spectral resolution image is realized,and a more complete band set is obtained.This method has been applied to the interpretation experiments of complex geological bodies such as magmatic complex interpretation,sedimentary unit interpretation and metamorphic mineralization alteration extraction.The following results have been achieved:1)According to the theory of Synergy and the characteristics of remote sensing imaging system,the synergistic idea of remote sensing data is summarized.Based on the principle of consistent spectral response of surface reflectivity of image pixels and improving the spatial resolution of multi-spectral data sources as much as possible,the synergistic application framework of multi-source satellite remote sensing is established.2)A spectral synergistic method based on statistical regression and band correlation is proposed.The spectral synergy factors of different sensors in similar wavelengths bands were established by statistical regression.At the same time,in the study of different wavelengths bands,the spectral synergistic factors are determined by relation and correlation of the spectral bands.Through spectral synergy,the differences in statistical parameters such as mean and standard deviation of surface reflectance values of different sensors' spectral bands are significantly reduced.3)The integral weight of spectral response function is introduced to improve the GS fusion method,which can improve the spectral fidelity through fusion process.The advantage of this method in spectral fidelity can be proved by the root mean square error(RMSE)test results of each resolution scale and each band with the original multispectral data.Through the multi-scale fusion experiment,the amount of image information and sharpness are evaluated by information entropy and variable window improved local variance respectively.Then the optimal synergy scale is determined and used as a spatial synergistic scale to construct a multi-source remote sensing synergy image set.4)The application effect of the synergistic processing method of multi-source remote sensing is verified and a suitable synergistic scheme is put forward for each study area.In Sanfengshan magmatic intrusive complex,Baicheng-Kuqa sedimentary area and Daqingshan metamorphic area and using suitable multi-source remote sensing data,The synergistic method of multi-source satellite remote sensing is applied to the interpretation of magmatic complex,the interpretation of sedimentary units and the extraction of mineralization and alteration of metamorphic rocks separately.Good results of interpretation and extraction are obtained,and the advantages of multi-source remote sensing synergistic method are verified by comparative experiments.The enhancement of intrusive unit,sedimentary unit difference and mineralization alteration which is not widely exposed on the surface all need the support of narrow band set by the corresponding wavelength position of SWIR and higher spatial resolution by spatial synergistic process to alleviate the serious influence of mixed pixels.In the study of interpretation of magmatic complex and sedimentary units,the spectral characteristics of the whole bands of synergistic images,reasonable band ratio set and principal component analysis should be applied in complex areas,so as to obtain more effective results of geological body boundary enhancement.In the metamorphic rock study area,the alteration related to the mineralization in the multiple spectral bands of wavelength positions are enhanced and extracted in the application,and it is proposed that if the spectral bands needed for single alteration enhancement all come from the same sensor,spatial synergistic process can be used singly to improve the resolution without spectral synergistic process.In this study,the results in each study area verifies that synergistic images have certain advantages in spectral information richness and spatial resolution,and also proves the effectiveness of spectral and spatial synergy.It provides a set of reasonable application method of multi-source satellite remote sensing data for the interpretation of complex geological bodies.