Loading...

Sunday, 22 May 2011

Science of Land Slide

Hill Slope

Heavy Rain
Detachment of soil bed from rock bed
Land Slide

Landslides are a form of mass movement, a term used to describe any sort of gravity-induced movement of sediment down a slope. Mass movements can occur slowly over a period of years, or they can happen in a matter of minutes. A mass movement can be as small as some rocks and debris you kick down a small incline or as big as the 1980 landslide set off by the eruption of Mount St. Helens.
­There are many different kinds of mass movements categorized by the type of material involved, the way it is moved and how fast it moves­. However, with any mass movement, a soil layer is separated to some degree from the underlying bedrock. Soil is the relatively loose mixture of worn-down rock, minerals, air, water and decayed organic matter that covers the ground. Bedrock is the more stable, solid layer of rock underneath.