Study and application of a new 3D geological model construction method

Modeling of 3D data about geological objects is key problem 3D geological GIS. In this paper, the methods on 3D spatial modeling and GIS about geological objects are reviewed. A new 3D geo-spatial modeling method, called similar tri-prism (STP), is proposed. In this method, the similar tri-prism is the basic body element of expressing 3D geological objects. Five kinds of basic elements and six groups of topological relationships are used to describe the data structure of STP. The STP mode can be combined with the conventional multi-layer TIN model. It can effectively express 3D geological objects and maintain the topological relationship. A 3D GIS primary prototype suitable for geological domain is developed and tested by borehole data from an exploration area in Inner Mongolia.