This entry refers to the geological term landslide. For the word's political usage, see landslide victory. In politics, a landslide victory (short form: landslide) is the victory of a candidate or political party by an overwhelming majority in an election. ...

A landslide is a geological phenomenon which includes a wide range of ground movement, such as rock falls, deep failure of slopes, and shallow debris flows, see flow. Although gravity acting on an over steepened slope is the primary reason for a landslide, there are other contributing factors: A Geological phenomenon is a phenomenon which is explained by or sheds light on the science of geology. ... FLOW is a J-Pop group. ... This article covers the physics of gravitation. ...

• erosion by rivers, glaciers, or ocean waves create oversteepened slopes
• rock and soil slopes are weakened through saturation by snowmelt or heavy rains
• earthquakes create stresses that make weak slopes fail (see the Hope Slide)
• volcanic eruptions produce loose ash deposits, heavy rain, and debris flows.
• vibrations from machinery, traffic, blasting, and even thunder may trigger failure of weak slopes
• excess weight from accumulation of rain or snow, stockpiling of rock or ore, from waste piles, or from man-made structures may stress weak slopes to failure and other structures

Slope material that become saturated with water may develop a debris flow or mud flow. The resulting slurry of rock and mud may pick up trees, houses, and cars, thus blocking bridges and tributaries causing flooding along its path. Severe soil erosion in a wheat field near Washington State University, USA. Erosion is the displacement of solids (soil, mud, rock, and so forth) by the agents of wind, water, ice, movement in response to gravity, or living organisms (in the case of bioerosion). ... For the Second World War frigate class, see River class frigate The Murray River in Australia A waterfall on the Ova da Fedoz, Switzerland A river is a large natural waterway. ... Austrias longest glacier, the Pasterze, winds its 8 km (5 mile) route at the foot of Austrias highest mountain, the Grossglockner A glacier is a large, long-lasting river of ice that is formed on land and moves in response to gravity. ... This article is about waves in the most general sense; a separate article focuses on ocean waves. ... This page is about the form of precipitation. ... Rain falling Rain on an umbrella Rain is a form of precipitation, as are snow, sleet, hail, and dew. ... Global earthquake epicenters, 1963–1998 An earthquake is a trembling or a shaking movement of the Earths surface. ... The Hope Slide was the largest landslide ever recorded in Canada. ... This article is about volcanoes in geology. ... See Oscillator (disambiguation) for particular types of oscillation and oscillators. ... A machine is any mechanical or organic device that transmits or modifies energy to perform or assist in the performance of tasks. ... Western vehicular traffic is generally organized, flowing in lanes of travel for a particular direction, with interchanges, traffic signals, or signage at intersectons to facilitate the orderly and timely flow of traffic. ... Explosive material - Wikipedia /**/ @import /skins/monobook/IE50Fixes. ... Thunder is the sound of the shockwave caused when lightning instantly heats the air around it to up to 30 000 °C (54 000 °F). ... In its earliest usage, trigger refers to a mechanical mechanism, the pulling or pushing of which sets a device into action. ... This article is about the edifice. ...

Similarly, ice floes can form in rivers that are clogged with ice, but are generally much slower moving. Nonetheless, they can generate forces strong enough to collapse bridges.

An avalanche is similar in mechanism to landslide and it involves a large amount of ice, snow and rock falling quickly down the side of a mountain. Usually the ice builds in cornices or forms over a weaker layer of snow, creating the danger of an avalanche. A Himalayan avalanche. ...

A pyroclastic flow is caused by a collapsing cloud of ash, poisonous gas and hot rocks from a volcanic explosion that moves rapidly down an erupting volcano. Pyroclastic flows are a common and devastating result of some volcanic eruptions. ... This article is about volcanoes in geology. ...

Landslides through history

• The Storegga Slide - Norway
• Frank Slide - Turtle Mountain, Alberta

The three Storegga Slides count among the largest recorded landslides. ... Norway - Wikipedia /**/ @import /skins/monobook/IE50Fixes. ... Motto: Fortis et Liber (Strong and free) Other Canadian provinces and territories Capital Edmonton Largest city Calgary Lieutenant Governor Norman Kwong Premier Ralph Klein (PC) Area 661,848 km² (6th)  - Land 642,317 km²  - Water 19,531 km² (2. ...

See also

• lahar
• shear stress
• geotechnical engineering

A lahar is a mixture of rock, mud, and water that flows down from a volcano (or occasionally other mountains), typically along a river valley. ... Shear stress is a stress state where the shape of a material tends to change (usually by sliding forces - torque by transversely-acting forces) without particular volume change. ... Geotechnical engineering is concerned with the engineering properties of earth materials. ...

Reference

• First-draft text taken from USGS fact sheet, public domain

External links

• United States Geological Survey site (http://landslides.usgs.gov/)
• British Columbia government landslide information (http://www.em.gov.bc.ca/Mining/Geolsurv/Surficial/landslid/)
• Slide!  (http://www.knowledgenetwork.ca/know_tool/slide/splash.html), a program on B.C.'s Knowledge Network, with video clips