An enhancement of reeb graph for modeling hydrogeological information

Abstract

Three-dimensional visualization has been useful for several geological information systems. Typical visualization methods in computer graphics usually cannot properly represent the multi-layer geographical data because of the lack of relation between each soil layer. In addition, some errors in the estimated position of soil layers and in the classification of soil layers can occur. This research, therefore, presents an enhancement of Reeb graph method for three-dimensional geological information providing the complex internal structure of soil layers. Proposed method can calculate major geological information, such as the positions of soil layers, the cross-sectional contours of soil layers at each height level corresponding to the input data. Firstly, the original Reeb graph is enhanced by changing from the relation between Reeb node and its contour to the relation between each Reeb node and its set of contours. Then, the surface is constructed from the set of contours. After specifying the position of each soil layer and constructing each surface for each soil layer according to the input depth, the cross-sectional contours of each soil layer at every critical height are then calculated using Morse theory. Next the enhanced Reeb graph is generated. Finally, the reconstructed surfaces represent the complete internal structure of the geological information. The experimental result shows that the proposed method can be efficiently applied for storing and displaying the cross-sectional data and the structure of soil layers of the hydrogeological information.