Taiyuan Graben Basin Quaternary Three-dimensional Geological Modeling And Buried Faults Primary Analysis

China network project of digital Earthquake observation—China seismic active fault surveying system is an event which is benefit for nation and people during the tenth five-year plan. Because 80% property damage and 60% population loss happened in some cities where the active fault existed, it is necessary to research the distribution and damage of seismic active fault hidden in the cities and to reduce the damage effectively.Taiyuan city is on the Taiyuan graben basin which is in the middle of Fen Wei graben belt. Taiyuan is a national earthquake danger area to which the government paid much attention in recent years. Therefore, the project of Taiyuan active fault surveying and earthquake risk estimation has been supported and paid much attention by ShanXi governments at the beginning.Based on the above-mentioned research subject, this paper has collected many kinds of geological and bore data and used the technology of three-dimensional visualize model integrated the spatial information administration, geology explanation, spatial analysis, geology statistic, three-dimensional picture visualization and so on to build a three-dimensional geologic model of Taiyuan graben basin in the quaternary period. This article directly describes the undulate variety of spatial stratum and primarily analyzes the stratum, faults distribution and activity of Taiyuan graben basin.The paper will build a spatial database of bore delamination through stratifying and tiding bore data. Using the powerful ArcGIS three-dimensional display function and making AO as the platform, it achieves the three-dimensional histogram of bore by designing algorithm; then it achieves three-dimensional visualization of stratum of three-dimensional vertical section and stratum interface and gets the three-dimensional stratum framework of quaternary period in Taiyuan graben basin by the collected bore materials.At last, based on the quaternary period 3-D geologic model of Taiyuan graben basin and combined all kinds of geological materials, we primarily analyze that Nanyan fault(F₁) breaks the stratum of Early Pleistocene and Medi-Pleistocene in the quaternary period; the strike of Fen River east and west fault (F₂,F₃) breaks the stratum of Early Pleistocene and Medi-Pleistocene on the quaternary period; the strike of Xincheng-Qinxian fault(F₄) breaks the stratum of Early Pleistocene, Medi-Pleistocene, and Late Pleistocene on the quaternary period.The achievement of this article is to build the 3-D geologic model of quaternary period in Taiyuan graben basin. It is the explorement and research of GIS in geology field. It is valuable on scientific research and application, and it can be used for reference to the development of active fault surveying project for other cities.