Abstract: According to the requirements of the 3D ore-body model of digital mine construction,the 3D reconstruction methcd of complex ore-body model based on the 2D contours of the plane or profile drawings of prospecting lines is analyzed,the method and coordinate transformation formula for convert 2D ore-body contours to 3D spatial polyline are proposed.Based on the oriented cycle of contour tiling algorithm,firstly,the wavelet filter bank is utilized to convert the contours into low resolution and similar shape with original contours,then,the optimal tiling is conducted of the low resolution contours,finally,the the low resolution contours are reconstructed successively by adopting the wavelet filter bank,besides that,the tiling result is locality reconstructed and optimized.The complexity of the oriented cycle of contour tiling algorithm is decreased in a large extent by using the multi-resolution contours tiling algorithm proposed in this paper,and the computation speed of the algorithm and model quality are improved effectively.The middle axis polyline between the neighbor parts of branch contours is calculated,the composite contour is splitted into closed branch contours,and they are reconstructed respectively,therefore,the branch composite problem is solved effectively.Taking the Dahongshan copper deposit as the study example,the ore-body contour of the plane and profile drawings of prospecting lines is grouped into different layers,they are converted into 3D modeling environment,the ore-body 3D model of the No.I iron copper deposit is established.The study results show that the 3D model of complex ore-body can be established effectively by adopting the 3D reconstruction method of 2D contour,which is good for the realization of the 3D visual mine decision and design.

Key words: Digital mine, Model reconstruction, Contours tiling, Oriented cycle of contour tiling algorithm, Wavelet filter, Branch composite