Regional assessment of geohazard recovery eight years after the Mw7.9 Wenchuan earthquake: a remote-sensing investigation of the Beichuan region
File(s)Liu-etal_EQ_recovery_Beichuan_IJRS-2017_final.pdf (1.83 MB)
Accepted version
Author(s)
Liu, Jianguo
Mason, Philippa J
Bryant, Eleanor C
Type
Journal Article
Abstract
The earthquake of 12 May 2008 in Wenchuan County, Sichuan Province, China, devastated the entire Beichuan region. Sitting at the intersection of the Yingxiu-Beichuan and Pengguan faults, the region experienced seismic intensities of VIII–XI on the Liedu scale. High seismic intensity combined with inherent geomorphological and climatic susceptibility to slope failure resulted in widespread co-seismic geohazards (slope failures of various types), which decimated the region. The seismic characteristics of the Wenchuan earthquake and the co-seismic geohazard distribution in relation to various conditioning factors have previously been examined in depth. However, there has been a lack of regional assessment of temporal and spatial recovery from co-seismic geohazards. Triggered by the authors’ field observation of rapid recovery, this study presents a temporal series of geohazard maps, produced by manual interpretation of satellite imagery, to present an initial assessment of changes in geohazard occurrence in the Beichuan region since the Wenchuan earthquake. In particular, landscape recovery at the co-seismic geohazard sites, as indicated by re-vegetation, is analysed based on temporal/spatial characteristics of geohazard distribution, in relation to co-seismic deformation, distance from the rupture zone and slope angle. Eight years after the Wenchuan earthquake, the overall recovery stands at 65.48%, with approximately uniform annual rates of recovery at 13.45% a year between 2009 and 2011 and 10.56% a year between 2012 and 2016. Whilst co-seismic geohazards are concentrated on the hanging wall of the seismic fault, landscape recovery is more significant in the very highly deformed zone than in other areas. Recovery has been the greatest on slopes of <50° and peaks on 40°–50° slopes, where the area occupied by co-seismic geohazards was the largest. The block-slides and rock topples, which characterize high angle slopes, show much slower recovery, possibly due to greater instability and the lack of soil to support re-vegetation.
Date Issued
2018-01-01
Date Acceptance
2017-11-13
Citation
International Journal of Remote Sensing, 2018, 39 (6), pp.1671-1695
ISSN
0143-1161
Publisher
Taylor & Francis
Start Page
1671
End Page
1695
Journal / Book Title
International Journal of Remote Sensing
Volume
39
Issue
6
Copyright Statement
© 2017 Informa UK Limited, trading as Taylor & Francis Group. This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Remote Sensing on 03 Dec 2017, available online: [insert hyperlinked DOI]
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000423204500004&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Technology
Remote Sensing
Imaging Science & Photographic Technology
LANDSLIDE HAZARD ASSESSMENT
CENTRAL TAIWAN
ASTER IMAGERY
CHINA
AREA
SUSCEPTIBILITY
DISASTERS
PATTERNS
BADONG
Publication Status
Published
Date Publish Online
2017-12-03