Minamata debris flow

Minamata debris flow

LCI : JPN1607131159
Main Information
Landslide Name : Minamata debris flow
Latitude : 32:12:40 N
Longitude : 130:25:33 E
Location
City / District : Minamata
Province : Kumamoto
Country : Japan
Reporter
Reporter 1 : Khang Dang
Reporter 2 : Kyoji Sassa
Landslide Type
Material : Debris
Movement : Flow
Velocity (mm/sec) : Extremely Rapid
Depth (m) : Moderate-Shallow
Slope (degree) : Moderate
Volume (m³) : Unknown
Date of Occurence
Date of Occurence : Jul 20, 2003
Other Information
Land Use Source area : Forest
Run-out/deposition area : Farming, Road
Other Activity : Active in the past
Triggering Factor : Rainfall
Death(s) & Missing : 15
Houses and other structural damage : 15
Photo of landslide : Aerial oblique view of the 2003 Minamata debris flow.png
Google earth kmz file : Minamata debris flow.kmz
Plan of landslide : -
Cross section of landslide : Cross section of Minamata landslide.png
Reference (paper/report) : http://link.springer.com/article/10.1007/s10346-003-0004-y
Testing graph : Test results.JPG
Monitoring graph : -
Video of moving landslides including 3D simulation : -
Description :

On 20 July 2003, a landslide occurred in an andesitic weathered lava layer on a mountain slope of 31–32 degrees in Minamata City, Kumamoto Prefecture, Kyushu Island, Japan. It was triggered by a heavy rainstorm with 314 mm total rainfall and a maximum rate of rainfall of 91 mm/h. The slide mass entered a torrent, where it was transformed into a debris flow that struck a village along the torrent, destroying 15 houses, killing 15 people, and injuring an additional six people. This debris flow was triggered by the slide, and the landslide mass flowed downstream along the torrent, increasing its volume by entraining material from the channel and weathered surface soils of the mountain slopes on both sides of the channel. Based on a topographic survey made after the landslide occurred, the initial slide was estimated to have occurred along a failure surface with an inclination of 26.5 degrees and depth of approximately 10–12 m. Source: Sassa, K., Fukuoka, H., Wang, G. et al. Undrained dynamic-loading ring-shear apparatus and its application to landslide dynamics. Landslides (2004) 1: 7. doi:10.1007/s10346-003-0004-y