Distribution characteristics of geohazards induced by the Lushan Earthquake and their comparisons with the Wenchuan Earthquake

The Lushan Earthquake induced a large number of geohazards. They are widely distributed and caused serious damages. The basic characteristics, formation mechanisms and typical cases of geohazards induced by Lushan Earthquake are described, and compares to the relationships of Lushan and Wenchuan earthquakes between geohazards and earthquake magnitude, geomorphology, slope angle, elevation and seismic intensity in the most affected areas in the article. (1) The numbers and volumes of landslides and rockslides differ significantly between the two earthquakes due to their differing magnitudes. The Lushan Earthquake is associated with fewer and smaller-magnitude geohazards, within the immediate area, which mainly consist of small-and medium-sized shallow landslides and rockslides, and occur on steep slopes and mountain valleys. The largest landslide induced by Lushan Earthquake is the Gangoutou Landslide debris flow with a residual volume of about 2.48×106 m3. The most dangerous debris flow is at Lengmugou gulley in Baoxing County, which has similar geomorphological features and disaster modes as a previous disaster in Zhouqu County, Gansu Province. (2) Geohazards induced by the Lushan Earthquake show four mechanisms: cracking-rockslides-collision-scraping and then debris flows, cracking-rockslides, vibration-rainfall-rockslides-landslide and then debris flow, vibration-throwing or scrolling. (3) There are significant similarities and differences between the geohazards induced by these two earthquakes. The types of geohazards are the same but the volume, quantity and other factors differ: geohazards are concentrated on slope angles of 10°–40° in the Lushan Earthquake area, especially within 10°–20°, and at absolute elevation of 500–2 000 m above sea level (a.s.l.). Geohazards within the Wenchuan Earthquake area are concentrated on steeper slope angles of 30°–40° at higher absolute elevations of 1 500–2 000 m.s.l..

[1]  Xiaoqing Chen,et al.  The 12 May Wenchuan earthquake-induced landslide lakes: distribution and preliminary risk evaluation , 2009 .

[2]  Zhu Qi.  INVERSE GRADING ANALYSIS OF DEPOSIT FROM ROCK AVALANCHES TRIGGERED BY WENCHUAN EARTHQUAKE , 2012 .

[3]  Keming Yang,et al.  Tectonic Evolution of the Middle Frontal Area of the Longmen Mountain Thrust Belt, Western Sichuan Basin, China , 2009 .

[4]  Chong Xu,et al.  GIS-based bivariate statistical modelling for earthquake-triggered landslides susceptibility mapping related to the 2008 Wenchuan earthquake, China , 2013 .

[5]  Chong Xu,et al.  Revisions of the M 8.0 Wenchuan earthquake seismic intensity map based on co-seismic landslide abundance , 2013, Natural Hazards.

[6]  Xu Chon.  LANDSLIDES TRIGGERED BY THE APRIL 20,2013 LUSHAN,SICHUAN PROVINCE M_S7.0 STRONG EARTHQUAKE OF CHINA , 2013 .

[7]  Weile Li,et al.  Analysis of the geo-hazards triggered by the 12 May 2008 Wenchuan Earthquake, China , 2009 .

[8]  E. Harp,et al.  Interpretation of earthquake-induced landslides triggered by the 12 May 2008, M7.9 Wenchuan earthquake in the Beichuan area, Sichuan Province, China using satellite imagery and Google Earth , 2009 .

[9]  Hiroyuki Fujiwara,et al.  Coseismic surface‐ruptures and crustal deformations of the 2008 Wenchuan earthquake Mw7.9, China , 2009 .

[10]  Z. hui.  Acta geologica sinica , 1988 .

[11]  Huabin Wang,et al.  Preliminary investigation of some large landslides triggered by the 2008 Wenchuan earthquake, Sichuan Province, China , 2009 .

[12]  Qiusheng Li,et al.  Deep Background of Wenchuan Earthquake and the Upper Crust Structure beneath the Longmen Shan and Adjacent Areas , 2009 .

[13]  Chuan Tang,et al.  Landslides induced by the Wenchuan earthquake and the subsequent strong rainfall event: A case study in the Beichuan area of China , 2011 .

[14]  R. King,et al.  A geological and geophysical context for the Wenchuan earthquake of 12 May 2008, Sichuan, People's Republic of China , 2008 .

[15]  Wen Xue-ze,et al.  Seismogenic structure of Lushan earthquake and its relationship with Wenchuan earthquake , 2013 .

[16]  Liang Bin,et al.  Geohazards Induced by the Lushan Ms7.0 Earthquake in Sichuan Province, Southwest China: Typical Examples, Types and Distributional Characteristics , 2013 .

[17]  Xinli Hu,et al.  Characteristics of landslides induced by the great Wenchuan earthquake , 2010 .

[18]  Ping Sun,et al.  Landslide hazards triggered by the 2008 Wenchuan earthquake, Sichuan, China , 2009 .

[19]  C. Westen,et al.  Distribution pattern of earthquake-induced landslides triggered by the 12 May 2008 Wenchuan earthquake , 2010 .

[20]  F. Wang,et al.  The motion mechanism of some long runout landslides triggered by 2008 Wenchuan earthquake, China , 2009 .

[21]  Bin Li,et al.  Catastrophic landslides associated with the M8.0 Wenchuan earthquake , 2011 .

[22]  Qiu Zhu-li.  The surface rupture zone distribution of the Wenchuan earthquake (Ms8.0) happened on May 12th, 2008 , 2008 .

[23]  Feng Zhen.  DYNAMIC RESPONSE CHARACTERISTICS OF DAGUANGBAO LANDSLIDE TRIGGERED BY WENCHUAN EARTHQUAKE , 2012 .

[24]  Dong Jia,et al.  Co-seismic thrusting rupture and slip distribution produced by the 2008 Mw 7.9 Wenchuan earthquake, China , 2009 .

[25]  Chong Xu,et al.  Three (nearly) complete inventories of landslides triggered by the May 12, 2008 Wenchuan Mw 7.9 earthquake of China and their spatial distribution statistical analysis , 2014, Landslides.

[26]  A. Ghulam,et al.  Focusing seismic energy along faults through time-variable rupture modes: Wenchuan earthquake, China , 2009 .

[27]  Yann Klinger,et al.  Coseismic reverse- and oblique-slip surface faulting generated by the 2008 Mw 7.9 Wenchuan earthquake, China , 2009 .