Seismic Risk Evaluation On Active Fault & Geodatabase Building In Urumqi

Strong earthquakes caused by offset of active fault in the urban range threaten directly the security of city and people's lives and properties. The urban activity fault surveying and seismic risk evaluation is a systematic project in service to reduce natural disasters in the city, and also is a new job that the study of active structure is up against. The research in my thesis is supported by"The active fault surveying and seismic risk evaluation project in Urumqi". Based on the work of the project, the urban active fault surveying, seismic activity appraisal, drill detecting across the active fault and trial trench exposure , we made seismic risk evaluation , built a geodatabase with all data inputted, and programmed an information system with VB.net for people to browse data. The purpose is to offer a basis for urban development planning.Firstly, we collected a large number of data produced during the survey, concerning physical geography, geochemistry foundation geography, and etc. Data are chosen according to the tasks related, which naturally realized data classification, to name one category data of physical geography. For the database system, the geographical information system platform under ArcGIS is adopted to arrange data and make spatial analyses. In order to improve the data sharing, all the data involved in the project are stored in Oracle through ArcSDE. By analyzing the available data we made seismic risk evaluation of the urban activity fault according to tasks raised by the urban activity fault surveying.For the convenience of non-professionals to browse the active fault data, the author develops the platform of software with good operating function -- active fault information system in Urumqi (which is similar to OUTLOOK navigate interface). The program was developed through VB.net and ArcGIS Engine components, which realizes basic GIS function. During the course of developing information system, aiming at the seismic risk evaluation of active fault, spatial data browsing module, spatial data management module, and etc. are set up on the basis of realizing the space data similar to ArcMap and view management to realize information in query, figure editor, thematic map, seismic risk evaluation etc.