Geological Knowledge Rule Constructing And Three-dimensional Modeling Based On Planar Geological Map

Three-dimensional geological modeling is able to express the geometry and attributes of geologic body visually and provide reference to rational use of underground space and geological resouces. It has become one of the hotspots of earth science research. However, traditional data sources for modeling,such as bore, profiles and geophysical information, are hard to obtain, limited in number, and unevenly distributed, which brought some obstacles to the study of three-dimensional geological modeling field.Planar geological map is an important achievement of regional geological studies, which combines geological knowledge of experts, reflects the topography and geologyl characteristics of the overall region, and has advantages such as low cost and easiness to obtain. Accordingly, taking planar geological map as modeling data source can alleviate the problems caused by traditional data source to some extent. In order to give decision support to geological research and underground engineering and promote the development of three-dimensional geological modeling theory, this paper takes planar geological map as major data source, uses geology knowledge rule set to mining implicit information in planar geological map, builds characteristic surfaces, expresses spatial extension and topological relation of stratigraphy and geological structure, consturcts shallow three-dimensional geological surface model of the region. Results and conclusions are as follows:(1)Summarize the the geometric elements and classification of fold and fault structures, analyze the manifestations of folds and faults in planar geological map. On this basis, using UML diagrams make formal expression of geometric elements and classification of folds and faults.(2)Build geology knowledge rule set to mining information in the planar geological map. Rule set system contains four rule sets which make researches from geological age,stratigraphic relationships, stratigraphic occurrence, structure morphology respectively. Rule set obtains indirect information by reasoning from direct information in the map to provide data support to geological modeling.(3)Propose a three-dimensional geological model that takes planar geological map as major data sources, combines with geological information obtained by rule set, uses surface model based on curved contour to express characteristic surface, constructs regional shallow three-dimensional geological surface model, which reproduces geological conditions of the region from a macro perspective. Study processing mechanism of intersect and deviation of characteristic surfaces to ensure topology consistency.(4)Select Typical experiment area and use the proposed method to construct three-dimensional geological model. The experiment shows that with the support and restraint of geology knowledge rule sets, stratum sufaces and fault planes can be constructed. The model can reflect the three-dimensional characteristics of shallow folds and faults in the study area, which verifies the feasibility of the method.