Factors that change the potential of mass wasting include:
change in slope angle, weakening of material by weathering
, increased water content; changes in vegetation cover, and overloading. Volcano flanks can become over-steep resulting in instability and mass wasting.
What are 5 events that can trigger a mass movement?
Factors that cause Mass Movements
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.
What are the 4 factors that influence mass wasting?
landslides. Mass wasting is the downhill movement of Earth materials under the pull of gravity. Mass wasting is influenced by
slope, material strength, water content, and amount of vegetation
. Mass wasting can be triggered by storms, earthquakes, eruptions, and human activity.
What are three causes of mass wasting?
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.
What are the controls and triggers of mass wasting?
Steep slopes, widely varying altitude ranges (relief), the thickness of the loose earth material, planes of weakness parallel to the slopes, frequent freezing and thawing, high water content in the earth material
, dry conditions with occasional heavy rainfall, and sparse vegetation are the factors that contribute to …
What human activities can influence mass wasting?
Humans can contribute to mass wasting in a few different ways:
Excavation of slope or its toe
.
Loading of slope or its crest
.
Drawdown
(of reservoirs)
What are the four main classes of mass movements?
- Rockfall. Bits of rock fall off the cliff face, usually due to freeze-thaw weathering.
- Mudflow. Saturated soil (soil filled with water) flows down a slope.
- Landslide. Large blocks of rock slide downhill.
- Rotational slip. Saturated soil slumps down a curved surface.
What is the most important factor in causing mass movements?
Gravity
is the main force responsible for mass movements. Gravity is a force that acts everywhere on the Earth’s surface, pulling everything in a direction toward the center of the Earth.
What force must be overcome in order for mass wasting to occur in most cases?
For mass wasting to operate on a sloped surface
the gravitational force
must be resolved into two vectors (Figure 7). One must be the downward force acting perpendicular to the sloped surface. This is the “Stay Force” component of the vertical pull of gravity.
Which mass movement is the fastest?
Landslides and avalanches
can move as fast as 200 to 300 km/hour. Figure 3. (a) Landslides are called rock slides by geologists. (b) A snow avalanche moves quickly down slope, burying everything in its path.
How can we prevent mass wasting?
Engineering solutions include
barriers and retaining walls, drainage pipes
, terracing the slope to reduce the steepness of the cuts, and immediate revegetation. Rockfalls can be controlled or eliminated by the use of rock bolts, cables, and screens and by cutting back slopes to lesser gradients.
How does mass wasting occur?
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. Often lubricated by rainfall or agitated by seismic activity, these events may occur very rapidly and move as a flow.
What are the effects of mass wasting?
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 …
What is the fastest type of mass wasting process?
A rock fall
are the fastest of all landslide types and occurs when a rock falls through the air until it comes to rest on the ground—not too complicated.
How does deforestation contribute to mass movements?
Deforestation can cause mass wasting
through erosion after trees are removed
. This is particularly bad in the tropical rain forest as the top soil washed away quickly and takes a long time to re-grow. The impact of mass movements increases as populations grow and cities expand into unstable areas.
What is landslide and its causes and effects?
On a slope downwards is called a landslide. It is a type of ” mass wasting ” which refers to the movement of any mass, soil, or rocks under the influence of gravity. … Landslides are caused because of
heavy rains, earthquakes, deforestation, volcanic eruptions, construction of roads, and buildings or houses, etc
.
