Q6 of 18 Page 66

Are there any possible places of landslide in your area? Collect information from experts.

Yes, there are places of landslide in my area. Landslides mostly do not occur in household areas. They can occur on roads, areas where buildings are constructed, heavy crackers bursting or some explosion etc. These landslides are aggravated by human activities, such as

Deforestation, cultivation and construction, which destabilize the already fragile slopes.


vibrations from machinery or traffic


blasting


earthwork which alters the shape of a slope, or which imposes new loads on an existing slope


● in shallow soils, the removal of deep-rooted vegetation that binds colluviums to bedrock


Construction, agricultural or forestry activities (logging) which change the amount of water infiltrating the soil.


A landslide is caused by gravity acting on an over-steepened slope. A variety of contributing factors are often responsible for their occurrence, but rainfall often plays a major role in failure.


Landslides are associated with hilly or mountainous landscapes. They are also common along coastlines and river valleys.


Landslides occur most frequently in regions where climate and precipitation, bedrock and soil conditions, and slopes are susceptible to failure.


Landslides are mostly likely to occur in areas where they have already occurred in the past. In many cases, the landscape features surrounding a location where recent landslide catastrophes have occurred provide evidence of past and ongoing landslide activity. Land sliding is part of the processes behind and evolution of the landscape.


But mostly are the natural causes of landslides, which include:


● groundwater (pore water) pressure acting to destabilize the slope


● loss or absence of vertical vegetative structure, soil nutrients, and soil structure (e.g. after a wildfire – a fire in forests lasting for 3–4 days)


● erosion of the toe of a slope by rivers or ocean waves


● weakening of a slope through saturation by snow melting, glaciers melting, or heavy rain


● earthquakes adding loads to barely stable slope


● earthquake-caused liquefaction destabilizing slopes


● Volcanic eruptions.


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