Earthquake Emergency Situation Plotting Technology Based on GIS

The classifications of earthquake emergency situation map elements are put forwarded,and the visualization symbol library of situation map elements is designed based the classifications.The library is composed of basic symbol level,unit symbol level and representation level.GIS based display method and realization procedure of the situation elements are described.A hash table based virtual layer manager is adopted to realize the display management of situation plotting symbols.Through constructing Nanjing earthquake emergency platform,the situation plotting module is realized.The feasibility and effectiveness of the situation plotting technology studied in this paper is verified in a real earthquake emergency drill.