9 Reasons to why Mass Wasting occurs

9 Reasons to why Mass Wasting occurs

Posted by Manisha on May 14, 2020

As you know Mass Wasting is also known as Mass Movement or Slope Failure and this is directly related to the slope and gravity. It has the power to change the total geomorphology (map) of an area and region, overnight. 

Do you know its causes, how it occurs? What factors help it to let this occur?

nine reason why mass wasting occurs
Reasons to why Mass Wasting occurs

Here are 9 main reasons and factors of mass wasting:

1. The gravitational force of Earth

It is the main basic factor of mass wasting. Earth has gravity power, which attracts everything towards the lower elevation (ground). This power of earth also applies here. It keeps trying to attract rocks, soil, regolith, rock debris, and others towards the lower elevation or lower case, which results in mass wasting.

2. The angle of the slope

There is a direct relation between slope and mass wasting. Higher the steepness of slope leads to higher intensity of mass wasting.
For example, that is why steep cuts around mountains and steep slope of mountains had higher intensity of mass wasting in the form of landslides, debris flow, etc.

  • Kedarnath Tragedy of Uttarakhand, India in June 2013, is a great example of this. There the destruction was on the vast level or you can say due to a higher angle of the slope the destruction became more intense and also difficult to help people and in the rescue operations, even after a tragedy or natural calamity.
  • This Kedarnath tragedy starts with a landslide in the Chorabadi lake which later leads to the flood, rock slide, mudflow, slumping, and debris slides, all together. 
  • This swiped away everything which came into their path.

3. Increased water content

Whenever higher lands, slopes, mountain areas, etc. absorb more water, due to rain, it loses their grip with their sand grains or soil land base, leads to mass wasting in the form of mudflow.
Running water like rain and river, also helpful in mass wasting.

4. The weakening of material by weathering

Weathering plays an important role in the breakdown of big rocks into smaller pieces and loosen them, which is later eroded by or tumbled down through the Mass Wasting process.

5. Overloading

Anything which is overloaded has nature to collapse, in the lack of balancing or instability, leads to mass wasting.

6. Vegetation cover

Vegetation works as the natural binder on soil particles and on the mountain slope.

  • Because trees and grassroots weaved into each other and do not let soil particles to move anywhere freely.
  • It has an inverse relationship between vegetation and mass wasting.
  • Lower vegetation leads to higher chances of mass wasting and vice versa.

7. Earthquake

Shaking of earth results in mass wasting. 

8. Volcano

Volcano flanks can become over steep resulting in instability and mass wasting.

9. Plant roots wedging

This is a process in which plants have grown into the cracks of rocks and slowly as they grow, their roots also have grown and increase these cracks, which leads to mass wasting.

For example, do you ever saw a peepal tree, which grows on the terrace of your home, or in any cracks of the wall, or any demolished building? (very common at the places where the interference of human being is very rare).
It could crack the whole house as it grows, just like plant roots wedging in mountain rocks leads to the breakdown of big rocks into smaller ones and later eroded.