Study on Classification Method of Rock Types Based on Topographic Indicators-Take Tengchong Research Area in Yunnan as an example

Due to the different types and properties of rocks, the digital elevation model surfaces are different after the dynamic action inside and outside the crust. Based on this, this paper uses macro and micro topographic factors derived from ASTER GDEM data to explore its mathematical definition and geological significance. Through curve fitting method, mean change point method, data statistical analysis, multivariate variance analysis, curve fitting method, mean change point method and maximum likelihood method to supervise classification, the optimal window size for extracting macro topographic factors in Tengchong research area of Yunnan Province is calculated, and the ability of topographic factors to distinguish different rock types is explored, so as to construct the classification accuracy of topographic index combination calculation. The research shows that: (1) The optimal window size for extracting macro topographic factors in Tengchong research area of Yunnan Province is 330m*330m, which can effectively control the topographic fluctuation period, fully reflect the topographic features and avoid the redundancy of information data. (2) Topographic factors can express the topographical features of different rock types from macro and micro perspectives. It is feasible to classify rock types quantitatively by combining topographic factors, and the classification accuracy is high and the effect is good.