Three Dimensional visualization of geological structure based on Geophysical field data

Qi Min, The Institute of Geology and Geophysics Chinese Academy of Science, China

Three dimensional visualization of geologic volume as one of the hot in the geosciences field, gathers all kinds of geological information and uses visualization technology to construct 3D geological model and all kinds of spatial object. It is convenient for geologists to describe the spatial distribution of geological objects, and to analyze the relations and law of the geological phenomena.

Traditional geological model is built by known information, such as ichnography 、section plane and drill histogram. But especially for the unexplored field and deep part of old diggings, drilling exploration is expensive, long period and skilled, so in the exploration stage, it must use right geophysical method to get geology information. How to transform a great deal of geophysical data to geological 3D model which geologist can see and feel is a problem to be settled. This is also the important problem of 3DGIS (3D Geographic Information System) and 3D GMS (3D Geosciences Modeling System).

This article, based on the former work, has researched and developed a 3D visualization system. It bases on the OO (orientated object) thought and modular programming, uses the C# language and Microsoft .NET platform which are the new product by Microsoft Corporation. This system firstly has built the high resistivity method and MT database. Data file uses Access Excel and SQL server types. System uses irregular tetrahedron to construct model and it has finally built the 3D geological model. There are some characters in this system, for example, it could define the geophysical parameters boundary to realize the transparency of some parts. It could show the real geographical coordinate real-time. It could set insert data times for the balance of efficiency and quality. It could set the geology volume color and analyze the regularity of geophysical parameters. This system has been already applied in predicting the complicated cavity in Shanxi province and searching hot water in Heilongjiang province and taken good effect on the result.

Keywords : three dimensional geological model, tetrahedron, high density electrical technique, MT, Microsoft.net, OpenGL