Landslides often have devastating effects on humans. The wall of mud wipes out buildings, covers roads and changes the landscape. The economic cost of landslides in the United States ranges from $1 billion to $2 billion annually. NBC News reports a death toll of 41 individuals with two missing from the March 22, 2014, landslide in Oso, Washington.Know More
Many landslides are the aftereffects of volcanoes or earthquakes. The damage they cause is often more significant than the damage caused by the triggering event.
Both natural and human forces increase the likelihood of a landslide. Activity at the base of the incline, such as the cutting action of a river or excavation by humans, removes some of the supporting material, giving gravity a greater advantage at moving the sediment from the higher layer.
According to HowStuffWorks.com, geologists classify landslides as "mass movement," a term describing any kind of "gravity induced movement of sediment down a slope." While some mass movements occur slowly over several years, landslides often occur in a matter of minutes. Mass movements are sometimes small, as when a deer kicks a few rocks down an incline. Others are large, such as the 1980 landslide due to Mount St. Helens' eruption. From a technical point of view, a landslide is a specific type of mass movement in which sediment loosens from its underlying bedrock along a distinct line of weakness, separates and moves down a slope in a rapid fashion.Learn More
The most common natural causes of landslides include volcanic eruptions, seismic vibrations from earthquakes, erosion beneath banks or cliffs and increases in pore water pressure. Human causes include deforestation, alterations to natural paths of drainage, pipe leaks and other activities placing significant pressure on landforms.Full Answer >
Landslides can result from a variety of both natural and human causes. Factors that influence landslides include slope angle, climate, weathering, water content of the land, vegetation, geology and slope stability.Full Answer >
The Coriolis effect plays a role in the flight paths of airliners as well as the formation and movement of hurricanes. The Earth's rotation imbues winds and objects that travel through the atmosphere with angular momentum due to the fact that the earth spins faster at the equator than it does near the poles.Full Answer >
The rain shadow effect occurs as warm, moist air rises against high elevations of land and drops its water along the way. This creates a region on the far side of the mountain range that is relatively deficient in precipitation to the point of forming a rain-shadow desert.Full Answer >