A Weighted Overlay Method for Liquefaction-Related Urban Damage Detection: A Case Study of the 6 September 2018 Hokkaido Eastern Iburi Earthquake, Japan

Geosciences

Sadra Karimzadeh¹  Masashi Matsuoka¹ 

[1] Department of Architecture and Building Engineering, Tokyo Institute of Technology, Yokohama 226-8502, Japan;

关键词: synthetic aperture radar;    Hokkaido Eastern Iburi earthquake;    InSAR;    LiquickMap;    damage;    microtremor;   

DOI  :  10.3390/geosciences8120487

来源: DOAJ

【 摘 要 】

We performed interferometric synthetic aperture radar (InSAR) analyses to observe ground displacements and assess damage after the M 6.6 Hokkaido Eastern Iburi earthquake in northern Japan on 6 September 2018. A multitemporal SAR coherence map is extracted from 3-m resolution ascending (track 116) and descending (track 18) ALOS-2 Stripmap datasets to cover the entire affected area. To distinguish damaged buildings associated with liquefaction, three influential parameters from the space-based InSAR results, ground-based LiquickMap (from seismic intensities in Japanese networks) and topographic slope of the study area are considered together in a weighted overlay (WO) analysis, according to prior knowledge of the study area. The WO analysis results in liquefaction potential values that agree with our field survey results. To investigate further, we conducted microtremor measurements at 14 points in Hobetsu, in which the predominant frequency showed a negative correlation with the WO values, especially when drastic coherence decay occurred.

【 授权许可】

Unknown