Geography 10 Landslides in Hong Kong Ms. Ripley
Mass Movement Unit Name:______
Landslides in Hong Kong.
Read this article and answer these questions:
1. Why do a lot of people live on slopes in Hong Kong?
2. What triggered the landslide in June 1972?
3. Explain the different methods used to prevent landslides in Hong Kong.
Hong Kong — flats that should not have been built
Hong Kong is a hilly island which has a rapidly growing population. Many people live in ______high-rise blocks of flats, some of which are built on the steep slopes of the island. The slopes are usually carefully surveyed to make sure that they are
stable before permission is given for any buildings to be constructed, but sometimes, unknown to the government planners, buildings have been sited
on unstable slopes. These are slopes on which soil creep and perhaps landslides may occur. Besides being hilly Hong Kong receives over 2000 mm of rain a year.
In June 192 about 200 mm of rain fell in one day with similar amounts falling on the following days. The result was disastrous. A landslide developed on one of Hong Kong’s slopes and within a few minutes it had cut across two roads arid demolished a high-rise block of flats causing more than 50 deaths. This landslide was triggered by the rapid convergence of rainwater in the soil on the upslope of the flats, causing the soil to become saturated and unstable. See Fig. 3.18. Landslides are always likely in urban areas on steep slopes in regions which have heavy rainfall. In
Hong Kong, attempts have been made to reduce the occurrence of landslides by planting trees on the slopes above the built-up areas and by covering other steep slopes with a kind of plaster. The trees bind the soil with their roots and they also absorb some of the rain water thus reducing the amount in the soil. The cement plaster helps to prevent the soil from becoming saturated by allowing the rain water to run off the surface instead of soaking into it. Landslides in these areas can be prevented if the soil on the exposed slopes is prevented from getting
saturated.
4. Fill in these missing words on the diagram.
4. Fill in these missing words on the diagram.
Continuous / Steep / Saturated