关键词: 汶川地震, 互联网, 灾情获取, 地震应急, 地震有感范围, 空间插值, GIS

Abstract:

Based on the felt information from the Internet after the earthquake, this paper studied the methods of earthquake damage information acquisition and analysis. We carried out the research based on 4515 pieces of felt information after the Wenchuan earthquake acquired from the Internet. After the analysis on the publishing time, location and intensity of the feeling of the earthquake in the felt information, we found that the release of felt information was concentrated within the 3 hours after the Wenchuan earthquake happened. And we initially identified 2 289 felt data released in the subsequent three hours after Wenchuan earthquake, which distributed in 199 areas, as the data sources for spatial interpolation. In order to do spatial interpolation for these datasets, we classified the datasets into three categories, which are "unawareness", "felt" and "strongly felt", and assigned the value of 0, 1 and 2 to "unawareness", "felt" and "strongly felt" respectively. Before doing the spatial interpolation for the datasets, we preprocessed the datasets distributed in 193 different areas to remove the redundant and abnormal value data and to finally extract 193 felt data distributed in different areas. At the same time, this paper did exploratory analysis for the datasets, by which we knew the law of the datasets and determined the parameters and model for the spatial interpolation. After a series of analysis, this paper adopted IDW, RBF and Kriging methods to interpolate the felt datasets, and get the results of the felt range of Wenchuan earthquake. Then, the paper compared the results from different spatial interpolation ways by interpolation accuracy and the goodness of fit with the actual earthquake disaster. After the comparison, we found that the result of Kriging method, with a certain interpolation model and parameters, was consistent with actual disaster distribution of the Wenchuan earthquake to a certain extent, especially for the fitting with the strongly felt area (Ⅵ degrees). This study provides an effective way for us to know quickly the earthquake felt range and correct for the disaster information of the earthquake. And it will play an important role in making scientific and rational decisions during the earthquake emergency.

Key words: Wenchuan earthquake, Internet, disaster acquisition, earthquake emergency, earthquake felt area, spatial interpolation, GIS