Research On Image Recognition Method Of Ancient Edition

The paleo-landmass is not only to be used to indicate crustal evolution history, but also is related to the uranium polymetallic mineralization, so it has important theoretical and practical significance to recognize the paleo-landmass. Currently, the researches on the paleo-landmass are mainly focus on geology features, such as geochemistry, geochronology and so on, lacking of study on integrated features of geoscience and recognition method. The North China craton is the biggest paleo-landmass in China, with a lot of small blocks in the northern margin. Anshan-Benxi paleo-landmass has an earlier evolution among the North China craton, with the record of landmass formation at 3800 Ma. In this area, besides the banded iron formation and non-ferrous metal deposits, it still have the oldest 3075 uranium deposit. This paper discusses the geological features of the paleo—landmass exemplified by Liaodong area in Anshan-Benxi paleo-landmass, and we try to introduce the fractal geometry and variogram to characterize the features of paleo-landmass, combined remote sensing, geophysical and other information. On such a basis, a remote sensing-geophysics process has been established, which is of great significance for the study of paleo-landmass.Based on the previous studies, this paper summarized the geological features of paleo-landmass firstly. Then we use Geophysics information to study the magnetic features of ancient metamorphic rocks, the gravity features of acidic magmatic rocks and the radioactive features of kaligranite. And remote sensing image information is used to distinguish ancient metamorphic rocks and mafic rocks, metamorphic rocks and sedimentary rocks, acidic effusive rocks and intrusive rocks, and different ages rocks. At last, regard the area which have both ancient metamorphic rocks and old kaligranite as the paleo-landmass, through the method of GIS spatial analysis. Major contributions of this paper are as follows.(1) Through analysis of magnetic susceptibility of 57 kinds of rocks, we find the average magnetic susceptibility of Archean metamorphic rocks are 27871.5×10-6, which is significantly higher than the average of lower Proterozoic, and much higher than Sedimentary and metamorphic rocks of other ages, except lower than intermediate-basic volcanic rocks. Based on the previous studies, identify the distribution of Archean metamorphic rocks and intermediate-basic volcanic rocks with magnetic anomaly.(2) The density of granitoid is 2.56 g/cm3~2.59g/cm3, which is in the low area of all rocks by the analysis of rock density parameter. And we identify the distribution of acidic magmatic rocks through the gravity anomaly information.(3) Compared with other rocks, kaligranite is characterized by significant radioactive, with higher content of K and lower U/Th.(4) Because of acidic magmatic rocks are rich in U,Th,K,compared with other geological units, we can use the radioactive data to figure acidic magmatic rocks out of other rocks.(5) For the remote sensing image of acidic effusive rocks and intrusive rocks, not only are the different from visual feature, but also have the differentia in multi spectrum. Intrusive rocks have more symmetric and less span multi spectrum than that of effusive rocks.(6) Since the different stages and duration of formation, granites of different ages have different texture complexity and developing features. Besides, old granites have wider span of multi spectrum than that of new granites.(7) With characteristic pectiniform river system, metamorphic rock images are obviously different from the visual feature of sedimentary rocks and igneous rocks, and have smaller variogram range.(8) Based on the geological meaning of paleo-landmass and the features of remote sensing and geophysics we summarize in this paper, we preliminarily build the identification process of the paleo-landmass, and try to be applied to the identification of Anshan-Benxi paleo-landmass. At last, in this paper, analysis the relationship between paleo-landmass and uranium mineralization.