A study on digital isoseisms fast drawing method based on GIS — Take an example of Yunnan Province

This paper discusses how to use the ArcEngine components and Orcale database to quickly draw the Yunnan Province digital isoseisms. Besides the current general ellipse model, the paper was the first time to complete the line source model of isoseisms drawing. At the same time, it improved the Binary search algorithm in order to quickly find closest active fault. Then the existing isoseisms file provided three correction methods: parameter correction, aftershocks correction and manual correction, which were respectively applied for the different data and purpose of the correction. Finally, taking an example of the simulation for Ning'er 6.4 and Lijiang 7.0 earthquake to demonstrate the method of fast drawing Yunnan digital isoseisms, and the method turned out to be feasible and practicable.