Major landslides and mudflows triggered by earthquakes and volcanic activity can cause thousands of casualties when they occur in densely populated areas.

Many recent examples have shown that earthquakes themselves can be very destructive, but they can also have disastrous indirect consequences such as landslides, rockfalls and avalanches.

Kyrgyzstan, a Central Asian republic situated in the middle of the Tian Shan Mountains, is particularly at risk of landslides triggered by earthquakes.

This is a direct consequence of the Tian Shan mountains’s youth and the high degree of tectonic and seismic activity in the area. This is related to the collision and convergence of India into Eurasia, which causes a high rate of crustal movement. Large earthquakes (M>6.0) are therefore frequent in this region.

The project aims to evaluate the landslide risk associated with earthquakes in the Tian Shan region of Kyrgyzstan. Aerial photograph interpretation, remote sensing analysis and field investigations will be used to draw up a landslide susceptibility map that will be of direct use for planners.

Socio-economic impact of the landslides in Kyrgyszstan

Danger for all
This Central Asian republic has a long history of landslides associated with earthquakes, some of which had catastrophic effects. For instance, in 1885 an earthquake took place along a main fault near Bishkek. This earthquake triggered several landslides. The major landslide in the Bielogorka area was 20-30 metres thick, 500 metres wide, and about 2000 metres long and carried 25 million m3 of material. The landslides obstructed a river, thereby impounding its water to create a lake.
In this century, three earthquakes triggered important landslides and avalanches that caused casualties. These landslides also destabilised mining tailings from former uranium mining activities, as a result of which uranium waste slid into the adjacent river.

In these inhabited and industrial regions, the problem of active tectonics and seismicity is changing from one of purely scientific interest to one of economic and human importance. Though the major cities are located in the plains, many small cities and villages are huddled in narrow valleys or close to escarpments. Moreover, nomads move their settlements up the mountains when they take their flocks to graze the summer pastures, where they are highly exposed to rockfalls.