Abstract: A supervoxel data model is introduced to represent exactly the complex space distribution of geological data in the coal mining area. Meanwhile, problems of continuity, involving B-Spline curves and fractal-based subdivide, can be also taken into account in this paper. Based on these theories and methods, an optimal technique for area filling contours based on multi-resolution is designed, enabling to greatly strengthen the reliability and stability of area filling contours in 3D mining GIS.