Co-seismic landslide detection using ALOS satellite image in the Mianyuan River Basin, China

Taking Mianyuan River Basin as case study, the co-seismic landslides were detected automatically using decision-making tree method on ALOS satellite imagery post the 2008 Wenchuan earthquake. These landslides cover an area of 48.5km
²
. The distribution of landslides was dominated by the seismogenic fault. Furthermore, the lithology determined the type of landslides. Shallow disrupted falls were mainly located in the hard rocks such as magmatic rocks and dolomites, while deep seated landslides were likely to occur in the strata with rigid upper layer and soft lower layer. Moreover, most landslides occurred within the elevation range from 1000 to 2000 m above sea level. In addition, most landslides occurred in the slope gradient range from 25 to 55 degrees. Slope direction also affects the distribution of landslides.