Evaluating triggering and causative factors of landslides in Lawnon River Basin, Taiwan

This study evaluates triggering and causative factors of landslides by comparing their occurrence in the Lawnon River Basin prior to and after rainfall and earthquake events over a five-year period (2005–2009). The landslide ratio in the study area was low (less than 4%) before 2007, and significantly increased in the wake of Typhoon Morakot in 2009. The high accumulation of rainfall was the major triggering factor. In addition, the major seismic activity of March 4, 2008 also contributed to landslide occurrence. The combined influence of rainfall and the earthquake is evaluated based on multi-variable regression analysis. Though no significant co-seismic landslides were found after the March 4, 2008 earthquake, its influence on slope stability has been observed from the apparent growth of landslide ratio in the four rainfall events following the quake. Causative factors include the higher landslide ratios occurring in sedimentary rock zones (especially sandstone formations with intercalations of shale), and dip slopes, which are demonstrably prone to plane failures.

[1]  E. Harp,et al.  Inventory of landslides triggered by the 1994 Northridge, California earthquake , 1995 .

[2]  Giovanni B. Crosta,et al.  Introduction to the special issue on rainfall-triggered landslides and debris flows , 2004 .

[3]  R. Schuster,et al.  Mass wasting triggered by the 5 March 1987 ecuador earthquakes , 1996 .

[4]  E. A. Rogozhin,et al.  Some observations of landslides triggered by the 29 April 1991 Racha earthquake, Republic of Georgia , 1994 .

[5]  C. F. Lee,et al.  Landslide characteristics and, slope instability modeling using GIS, Lantau Island, Hong Kong , 2002 .

[6]  Chen Chien-Yuan,et al.  Rainfall duration and debris-flow initiated studies for real-time monitoring , 2005 .

[7]  Fausto Guzzetti,et al.  Geographical Information Systems in Assessing Natural Hazards , 2010 .

[8]  A. Brimicombe,et al.  APPLICATION OF GIS TO HAZARD ASSESSMENT, WITH PARTICULAR REFERENCE TO LANDSLIDES IN HONG KONG , 1995 .

[9]  Richard Dikau,et al.  Databases and GIS for landslide research in Europe , 1996 .

[10]  Chjeng-Lun Shieh,et al.  Impact of Chi-Chi earthquake on the occurrence of landslides and debris flows: example from the Chenyulan River watershed, Nantou, Taiwan , 2004 .

[11]  W. M. Brown,et al.  Real-Time Landslide Warning During Heavy Rainfall , 1987, Science.

[12]  C. Chen.  Sedimentary impacts from landslides in the Tachia River Basin, Taiwan , 2009 .

[13]  Robert K. Mark,et al.  Statistical and Simulation Models for Mapping Debris-Flow Hazard , 1995 .

[14]  D. Varnes.  Landslide hazard zonation: A review of principles and practice , 1984 .

[15]  Ming-Lang Lin,et al.  Statistical approach to earthquake-induced landslide susceptibility , 2008 .

[16]  G. Wieczorek,et al.  Effect of rainfall intensity and duration on debris flows in central Santa Cruz Mountains, California , 1987 .

[17]  Fu-Shu Jeng,et al.  Influence of petrographic parameters on geotechnical properties of tertiary sandstones from Taiwan , 2004 .

[18]  B. Khazai,et al.  Evaluation of factors controlling earthquake-induced landslides caused by Chi-Chi earthquake and comparison with the Northridge and Loma Prieta events , 2004 .

[19]  N. Caine,et al.  The Rainfall Intensity - Duration Control of Shallow Landslides and Debris Flows , 1980 .

[20]  Ming-Lang Lin,et al.  Statistical approach to storm event-induced landslides susceptibility , 2008 .

[21]  D. F. VanDine,et al.  Debris flows and debris torrents in the Southern Canadian Cordillera , 1985 .

[22]  Alberto Carrara,et al.  Multivariate models for landslide hazard evaluation , 1983 .

[23]  D. Keefer.  Landslides caused by earthquakes , 1984 .

[24]  Yanluan Lin,et al.  EVALUATING LANDSLIDES AND SEDIMENT YIELDS INDUCED BY THE CHI-CHI EARTHQUAKE AND FOLLOWED HEAVY RAINFALLS ALONG THE TA-CHIA RIVER , 2007 .

[25]  D. Varnes.  SLOPE MOVEMENT TYPES AND PROCESSES , 1978 .

[26]  W. Z. Savage,et al.  Gravitational spreading of steep-sided ridges (“sackung”) in Western United States , 1976 .

[27]  Shou-Heng Liu,et al.  Impacts of the Chi-Chi earthquake on subsequent rainfall-induced landslides in central Taiwan , 2006 .

[28]  David J. Unwin,et al.  Modelling landslide distribution on loess soils in China: an investigation , 1992, Int. J. Geogr. Inf. Sci..

[29]  D. Cruden.  A simple definition of a landslide , 1991 .