Based on the intersected geological sections, this paper puts forward a kind of 3D geological modeling method based on the division of spatial units. On the basis of self-governing thought, the method divides the complex overall regional into some single cells, and then to construct 3D geological model within each cell. After all the cells' model have been completed, all the models within the cells are merged to form the final overall model in the modeling area. Compared with the modeling method based on approximate parallel section data, this method can effectively overcome the disadvantages of only can choosing a single direction (horizontal or vertical). this method can meet the requirements of large area of 3D geological modeling in city. The proposed method is applied to quaternary 3D geological modeling for one city in china. Intuitive 3D geological model is established, based on the model built, therelated analysis and geological evaluation work on the model can be carried out.

Spatial units, intersected cross-section, cells

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