Geomorphic Processes is an important topic to be asked in the UPSC Civil Services Exam.

In this article we will cover topics such as the meaning of Geomorphic Process, topography of the Earth, types of geomorphic processes and more. Stay tuned to Testbook to get a detailed account of Geomorphic Processes for your UPSC exams.

• The forces like endogenic and exogenic which cause physical stress and chemical actions on the earth material and also bring changes in the configuration of the earth surface is called the Geomorphic process. Examples of endogenic processes are: Diastrophism and volcanism whereas examples of exogenic processes are: Weathering, Mass wasting, Erosion & Deposition. 
• Nature’s exogenic material has the ability to transport earth material and that’s why they are called Geomorphic agents. When these elements are portable because of the presence of gradients then they have the ability to remove the materials and transport them over slopes and deposit them at a lower level.
• Gravitational stress is also considered as important as other geomorphic processes. The force of gravity is keeping us in contact with the surface and it is the force that switches on the movement of all surface material on earth.

Geomorphic Processes (UPSC Geography) NCERT Notes: Download PDF Here

Why Is The Earth Uneven?

Because of both external and internal forces earth is continuously changing its surface condition. Crust of the earth is always dynamic in nature and it shows both vertical and horizontal movement. Because of differences in the internal forces making the surface uneven Wearing down of relief features is termed as  gradation. The forces which parts of the earth’s surface are called endogenic force whereas the processes fail to even out the relief variations of the surface of the earth is called exogenic process. 

This variation will remain only upto as long as there is difference between endogenic and exogenic forces.

You can check NCERT notes on Earth – Origin & Evolution here.

Types of Geomorphic Processes

• Endogenic Process: 

The energy which is coming from within the earth is the main force behind the endogenic geomorphic processes. This generation of energy can be because of various processes like: radioactivity, rotational force, tidal friction, primordial heat from the origin of the earth. Endogenic processes like Diastrophism And Volcanism are because of geothermal gradients and flow of heat within the Earth whereas crustal thickness, strength, action Of endogenic forces are because of variation in the geothermal gradient and uneven flow of heat. 

Diastrophism: 

Processes which moves, elevate or build up the portion of the earth’s crust come under

diastrophism.

Types of Diastrophism:

Orogenic processes: mountain building through folding

 Epeirogenic processes: uplifting large part of earth crust

Earthquakes

Plate tectonics: involve horizontal movements

Volcanism: 

Volcano is the movement of molten rocks towards the earth’s surface along with formation of many intrusive and extrusive volcanic forms. The process with which a volcano takes place is called volcanism. 

• Exogenic Processes: 

The energy for these processes is derived from the atmosphere determined by the prime source. The prime sources are the sun and also gradients created by the tectonic factors. Whereas gradient towards the down slope direction is created by the gravitational force.

Check NCERT notes on Volcanoes here

Denudational Processes And Their Driving Forces

Denudation is a general term which is used to cover all exogenic processes. The term “denude” means uncover. Processes which come under denudation are weathering, mass wasting erosion and transportation are included in denudation.

The driving force called energy on the Earth surface thermal gradient is caused by following factors:

• Latitude 
• Seasons 
• Land And Water Distribution 
• Angle Of Earth’s Inclination 
• Natural vegetation density is greatly influenced by the temperature and the precipitation and indirectly helpful in the exogenic process. 

You might also like: NCERT notes on Factors Controlling Temperature Distribution here.

Factors of Climatic Variation

Factors for climatic variation are listed below:

• Altitude
• Angle Of Slope
• Ocean Currents
• Amount Of Insolation Received By The Region
• Wind Velocity And Direction
• Direction Of The Slope
• Amount And Kind Of Precipitation
• Relation Between Precipitation And Evaporation
• Daily Rang Of Temperature
• Freezing And Thawing Frequency
• Depth Of Frost Penetration

You might also like: NCERT notes on Koppen’s Climate Classification

Weathering

Process of disintegration and chemical decomposition of rocks through the actions of various elements so weather and climate is called the weathering process. In this process there is no motion of materials taking place on site. 

Factor influencing the weathering process and depth of weathering: 

• Chemical weathering:

Weathering caused by an alteration to the chemical composition of the rock due to a reaction is called chemical weathering. Acidic water has the ability to dissolve rock. For example: acidic rain changes the chemical composition of limestone to form a limestone pavement. 

• Physical weathering: 

Process of weathering of rocks into smaller pieces with the help of exfoliation, freeze-thaw cycles, abrasion, root expansion, and wet-dry cycles. 

Exfoliation is the process of sudden change in the temperature of rocks that can expand or crack rocks.

• Biological weathering: 

Effects which are caused by living things are called biological weathering. For example: roots of trees penetrate the rock that creates cracks in rock which leads to disintegration of the rocks.

Check detailed NCERT notes on  Weathering here.

Significance of weathering: 

• Weathering process leads to formation of soil and erosion. 
• Weathering of rock and deposition helps in the enrichment and concentrations of certain valuable ores of iron manganese, aluminium copper.it is an important process of soil formation.
• Weathering leads to mass movement as these movements lead to the transfer of mass of rock debris down the slopes under the direct influence of gravity.

We hope the above NCERT Notes Geography(NCERT) -Geomorphic Processes  for UPSC aspirants proves to be useful for your UPSC and other competitive exams preparations. For more notes and updated details, download the Testbook App and get exam-ready in no time!