**2.4.2 Secondary geological disaster remote sensing monitoring results**

The overall results of monitoring secondary geological disaster are shown in Figure 3, where the red stands for landslides, blue for debris flows, and green for collapses. As can be seen from the figure, the landslide occurred mainly in Beichuan, Pingwu and Qingchuan counties; debris flow occurred mainly in Wenchuan, Maoxian and Li counties; and collapse occurred mainly in Wenchuan and Beichuan counties. According to statistics, the total disaster area is about 29,000 square kilometers, and the secondary geological disaster area is 2,250 square kilometers ( 7.8% of the total).

Fig. 3. Map of secondary geological disasters occurring in the heavily-hit areas of the Wenchuan earthquake
