The methods of 3D stratum modeling by multi-DEMs and triangular prisms can cause many redundant triangular-facets and slim triangular-prism meshes

so they aren’t propitious to fast scan the 3D stratum model

or used for the numerical simulation meshes. The TIN model can adjust the area and amount of the triangular-facets

so it can avoid redundant data

when it is used to represented the stratum interface. The TIN model can be built by the incremental insertion algorithm with the discrete points

and converted from grid (generated by Kriging interpolation) by greedy insertion; and it also can be built by the topographic contours. The cutting method between TIN models is presented to implement Boolean operations for stratum interfaces and faults 3D modeling. The multi representation methods are developed with the Visualization ToolKit; and the stratum body can be vividly represented by controlling the layer’s color

texture and material. At last the 3D stratum model of Longtan Hydropower Station is built to validate the theories and programs.