Mass movements affect the following elements of the environment: (1) the topography of the earth’s surface, particularly the morphologies of mountain and valley systems, both on the continents and on the ocean floors; (2) the character/quality of rivers and streams and groundwater flow; (3) the forests that cover much …

Such factors include: weathering or erosional debris cover on slopes, which is usually liable to mass movement; the character and structure of rocks, such as resistant permeable beds prone to sliding because of underlying impermeable rocks; the removal of the vegetation cover, which increases the slope’s susceptibility …

The factors that cause most mass movement events are the undercutting of steep slopes, the removal of vegetation, earthquakes, and heavy prolonged rainfall. Many mass movement disasters are preceded by development, deforestation, and slope steepening, which weakens the slopes.

Mass movement control must be primarily preventive: e.g., mapping vulnerable zones, drawing up a land use plan, banning building work or any modification of slopes, and protection in the form of coppice forests.

The causes of mass wasting include an increased slope steepness, increased water, decreased vegetation and earthquakes. One of the types of mass wasting that is an example of the slope failing is a slump. This is the sliding of coherent rock material along a curved surface.

Types of Mass Movement: Creep; Fall, Slip, Flow; Solifluction; Rock Glaciers; Slumping (Earthflow); Mudflow (lahar); Debris Flow, Debris Slide, Debris Avalanche; Rockslide; Rockfall; Debris Fall.

Mass wasting is the movement of rock and soil down slope under the influence of gravity. Rock falls, slumps, and debris flows are all examples of mass wasting.

Solifluction and creep are the slowest types of mass movement. Creep is the slowest of all the mass movements and moves the most soil out of all the mass movements. The only way to detect soil creep is to observe the fences, buildings, and other surface objects that may be in that area.

Concise Medical Dictionary, by Joseph C Segen, MD mass movement. Synonyms: Mass peristalsis.

Mass movement is the movement of earth materials called regoilth down a slope under the influence of gravity. Water and gravity cause the soil to move slowly downhill. This movement is shown on the features of the surface.

Rockfall is a natural mass-wasting process that involves the dislodging and rapid downslope movement of individual rocks and rock masses. The widespread combination of steep slopes capped by well-jointed bedrock makes rockfall among the most common slope-failure types in Utah.

How does water trigger mass movements? Water fills the pores in sediment, allowing the particles to slide past one another more easily. If the steepness of a slope exceeds that angle, mass movements become more likely.

The deadliest variety of debris flow is the debris avalanche, a rapidly churning mass of rock debris, soil, water, and air that races down very steep slopes. It has been theorized that trapped air may increase the speed of an avalanche by acting as a cushion between the debris and the underlying surface. Creep.

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. earthquakes of magnitude 4.0 and greater have been known to trigger landslides.

How does water affect mass wasting processes? Water in pores and cracks displaces air, so water adds to the mass of soil and broken rock on a slope. If pores and cracks are saturated (filled with water), the pore pressure tends to push the material particles apart, further promoting failure and downslope movements.

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Water in pores and cracks displaces air, so water adds to the mass of soil and broken rock on a slope. If pores and cracks are saturated (filled with water), the pore pressure tends to push the material particles apart, further promoting failure and downslope movements.

Human activity is one of the causes of mass movement. Increased human activity would increase the driving forces of mass movement. The density of the human activity, such as infrastracture, plus the pull of gravity would increase the likelihood of a landslide or a mudslide, or weaken a part of the slope.

Landslides and avalanches are the most dramatic, sudden, and dangerous examples of earth materials moved by gravity. Landslides are sudden falls of rock, whereas avalanches are sudden falls of snow.

Mass movements can sometimes be avoided by employing engineering techniques to make the slope more stable. Among them are: Steep slopes can be covered or sprayed with concrete covered or with a wire mesh to prevent rock falls. Retaining walls could be built to stabilize a slope.

Which of the following human activities can contribute to mass movement? any human disturbance of a slop, including roadcuts, surface mining, and development.

The impact of a landslide can be extensive, including loss of life, destruction of infrastructure, damage to land and loss of natural resources. Deep landslides, triggered by major earthquakes or volcanic activity can destroy thousands of square kilometres of land and kill thousands of people.

Human activities can effect slope stability through overloading the slope (waste, reservoirs) undercutting the slope (roads, quarrying, mining) vegetation removal (deforestation), cultivation (ploughing). Generally, however, these serve to accentuate slope instability rather than being the only cause.

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

Mount St. Helens

Bottom line: Landslides are mainly caused by gravity acting on weakened rocks and soil that make up a sloping area of land. Both natural and human-related activities can increase the risk for landslides. Water from heavy rainfall is a frequent trigger for landslides.

Landslides are caused by disturbances in the natural stability of a slope. They can accompany heavy rains or follow droughts, earthquakes, or volcanic eruptions. Mudslides develop when water rapidly accumulates in the ground and results in a surge of water-saturated rock, earth, and debris.

In simple terms, a hazard is a dangerous situation or event that carries a threat to humans. A disaster is an event that actually harms humans and disrupts the operations of society. Hazards will be considered disasters once they affect humans, but if they occur in an unpopulated area, they will remain hazards.