The impact of millions of raindrops hitting the bare soil surface can be incredible, dislodging soil particles and splashing them 3 to 5 feet away . A heavy rainstorm may splash as much as 90 tons of soil per acre. However, the majority of the soil splashed is not immediately lost from the field.

Answer. Rainwater, or snow melt, either soaks into the ground to become groundwater, evaporates, or flows over the surface of the land. The water that flows over the ground is called stormwater or runoff.

More rain equals more chemical reactions to weather minerals and rocks. In warmer regions, plants and bacteria grow faster, which helps to weather material and produce soils. In tropical regions, where temperature and precipitation are consistently high, thick soils form.

The rainfalls have a double effect: reduce the soil cohesion and increase the pore pressure. This influence of the rainfall on slope stability depends of the duration and intensity of the rainfall. This triggering factor is generally rainfall or earthquakes.

Experts said that the primary reason for the Oso mudslide was rain. Water can trigger landslides and mudslides because it alters the pressure within the slope, which leads to slope instability. Consequently, the heavy water-laden slope materials (soil, rock, etc.) will succumb to the forces of gravity.

Rainfall-induced landslides are a common occurrence in terrain with steep topography and soils that have degradable strength. Rainfall infiltration into a partially saturated slope of infinite extent can lead to either a decrease or complete elimination of soil suction, compromising the slopes’ stability.

Landslide Warning Signs

• Springs, seeps, or saturated ground in areas that have not typically been wet before.
• New cracks or unusual bulges in the ground, street pavements or sidewalks.
• Soil moving away from foundations.
• Ancillary structures such as decks and patios tilting and/or moving relative to the main house.

There are also various direct methods of preventing landslides; these include modifying slope geometry, using chemical agents to reinforce slope material, installing structures such as piles and retaining walls, grouting rock joints and fissures, diverting debris pathways, and rerouting surface and underwater drainage.

The health hazards associated with landslides and mudflows include: Rapidly moving water and debris that can lead to trauma; Broken electrical, water, gas, and sewage lines that can result in injury or illness; and.

Landslides can cause seismic disturbances; landslides can also result from seismic disturbances, and earthquake-induced slides have caused loss of life in many countries. Slides can cause disastrous flooding, particularly when landslide dams across streams are breached, and flooding may trigger slides.

Almost every landslide has multiple causes. Landslides can be initiated in slopes already on the verge of movement by rainfall, snowmelt, changes in water level, stream erosion, changes in ground water, earthquakes, volcanic activity, disturbance by human activities, or any combination of these factors.

Landslides occur when ground on slopes becomes unstable. Given the nature of such disasters, fast relief and rescue operations are required to get to trapped survivors but this can be delayed due to landslides cutting off easy access to the affected area.

Many human-caused landslides can be avoided or mitigated. They are commonly a result of building roads and structures without adequate grading of slopes, poorly planned alteration of drainage patterns, and disturbing old landslides.

Human activities can increase landslide risks. They include clear-cutting, mining and quarrying, bad agricultural practices, and construction activities.

Construction works, legal and illegal mining, as well as the unregulated cutting of hills (carving out land on a slope) caused most of the human-induced landslides.

Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.

Explanation: Because the thunder can cause of fire to the forest, when the tree is burned by thunder there will be no left to the forest and will have a landslide.

eruption of Mount St. Helens

Deforestation generally increases rates of soil-erosion, by increasing the amount of runoff and reducing the protection of the soil from tree litter. Trees removal on steep slopes with shallow soil thus increases the risk of landslides, which can threaten people living nearby.

Conclusion. Landslides are a dangerous hazard that can cause serious damages, death, injuries and affect a variety of resources. By understanding the different types and causes of landslides it can help us predict future occurrences and reduce the potential effects.

Nigeria

The most common cause of death in a landslide is trauma or suffocation by entrapment. Broken power, water, gas or sewage pipes can also result in injury or illness in the population affected, such as water-borne diseases, electrocution or lacerations from falling debris.

Countries where there are frequent landslides include China, the western United States, Italy, Switzerland, Japan, the Philippines and Indonesia. Countries that straddle the Himalayas such as Nepal, Pakistan and India are also areas where there are a large number of landslides.

Landslides occur in every state and U.S. territory. The Appalachian Mountains, the Rocky Mountains and the Pacific Coastal Ranges and some parts of Alaska and Hawaii have severe landslide problems. Any area composed of very weak or fractured materials resting on a steep slope can and will likely experience landslides.

Landslides are a serious geologic hazard that occurs in almost all 50 states. Every year in the United States, they cause significant damages and 25 to 50 deaths. Globally, landslides cause billions of dollars in damages and thousands of deaths and injuries each year.

On steep hillsides, debris flows begin as shallow landslides that liquefy and accelerate. A typical landslide travels at 10 miler per hour, but can exceed 35 miles per hour.

A landslide is a mass of soil sliding down a hillside. Large trees help retain soil and lean over. Smaller trees grow with a bend in the trunk. In Figure 1 the soil appears to be flowing down hill like a thick oatmeal mix.

A landslide is the movement of rock, earth, or debris down a sloped section of land. Landslides are caused by rain, earthquakes, volcanoes, or other factors that make the slope unstable. Geologists, scientists who study the physical formations of the Earth, sometimes describe landslides as one type of mass wasting.