A landslide is a form of mass extinction involving a variety of earth movements such as rockfalls, deep slope failure, and shallow debris. Landslides can occur underwater called underwater landscape, coastal and onshore environment. Although it is the primary driving force for gravitational drift, there are other factors that affect the original slope stability. The actual slip usually requires a trigger before it is published, whereas typically, the pre-conditional factors are to create specific subsurface conditions prone to slope failure. The landslides should not be mixed with the mud which is a mass depletion form associated with a very rapid rash flow partially or totally liquefied by adding significant quantities of water to the starting material.
Causes of Landslides
- Destabilize of Slope reason groundwater
- There is no vertical vegetative structure, soil nutrients, and soil structure
- Erosion reasons to river or sea waves
- weakening of a slope to snow and glacier melting
- Earthquake disrupt of slope
- Volcanic eruptions.
Types of Landslides
A Debris Flow is basically a fast-moving landslide made up of liquefied, unconsolidated, and saturated mass that resembles flowing concrete. In this respect, they are not dissimilar from avalanches, where unconsolidated ice and snow cascades down the surface of a mountain, carrying trees and rocks with it.
A common misconception is to confuse debris flows with landslides or mudflows. In truth, they differ in that landslides are made up of a coherent block of material that slides over surfaces. Debris flows, by contrast, are made up of “loose” particles that move independently within the flow.
Similarly, mud flows are composed of mud and water, whereas debris flows are made up larger particles. All told, it has been estimated that at least 50% of the particles contained within a debris flow are made-up of sand-sized or larger particles (i.e. rocks, trees, etc).
Overpressured zones (including gas and shallow water flows)
Overpressured zone is oil and gas blast out of underground trap machanism to under high pressure. Usually these zones occur oil and gas drilling process
During the 1991 Gulf War, the retreating Iraqi soldiers dynamited the wellheads off more than six hundred Kuwati oil wells, creating one of the biggest man-made environmental disasters in history. Since most Kuwati wells flow without pumps under their own great pressure, the oil and gas erupted from the ground with tremendous force. It was first estimated that it would take 2 years to repair all the wells. However, the heroic and extremely dangerous job was actually done in about six months.
Mud flows, diapirism and volcanism/volcanoes
Mud flow definition is extremely rapid surging flow to become significant amount of water to the source material. Mud mostly contain clay ,so ıt makes more fluid depris lows.
Areas at risk
- Areas where wildfires or human modification of the land have destroyed vegetation
- Areas where landslides have occurred before
- Steep slopes and areas at the bottom of slopes or canyons
- Slopes that have been altered for construction of buildings and roads
- Channels along streams and rivers
- Areas where surface runoff is directed
A flood basalt is the result of a giant volcanic eruption or series of eruptions that covers large stretches of land or the ocean floor with basalt lava. Flood basalt provinces such as the Deccan Traps of India are often called traps, after the Swedish word trappa (meaning “stairs”), due to the characteristic stairstep geomorphology of many associated landscapes. Michael Rampino and Richard Stothers (1988) cited eleven distinct flood basalt episodes occurring in the past 250 million years, creating large volcanic provinces, plateaus, and mountain ranges. However, more have been recognized such as the large Ontong Java Plateau, and the Chilcotin Group, though the latter may be linked to the Columbia River Basalt Group. Large igneous provinces have been connected to five mass extinction events, and may be associated with bolide impacts.