What are Endogenic and Exogenic Forces? IAS Geography Notes
Endogenic forces have been a recurring and important topic in Geography for IAS entrance examinations. In this article, we will cover the crucial aspects of endogenic forces that are significant from the IAS preparatory aspect. Let’s start with what are endogenic forces?
What are Endogenic and Exogenic Forces?
Clearly, the surface of the earth is not flat but is rather unevenly spread out due to the presence of landforms including mountains, plains, hills, etc. These uneven landforms are formed and deformed over a while, in an ongoing process, due to the influence of internal and external pressure from within and above the surface of the earth.
Simply put, we can define endogenic forces (internal) and exogenic forces (external) as the two major geomorphic pressures that lead to the earth’s movements and give shape to the earth’s surface.
When these internal and external changes occur continuously, chemical changes and stress are triggered on the surface of the earth, which eventually leads to the formation of uneven terrains.
Endogenic Forces – Internal Forces
Endogenic forces or endogenetic forces are the pressure that originates inside the earth, therefore also called internal forces. These internal forces lead to vertical and horizontal movements and result in subsidence, land upliftment, volcanism, faulting, folding, earthquakes, etc.
It Includes the Following Features:-
- Endogenic forces are land building forces that play a crucial role in the formation of the earth’s crust.
- These are also called internal pressure as they form, originate and are located below the surface of the earth.
- Primordial heat, radioactivity, tidal and rotational friction from the earth results in the creation of this energy.
- The main processes involved under this are volcanism, folding, and faulting.
The Endogenetic Forces can be Further Broken Down into Two Major Forms:
- Slow movements: These are also referred to as Diastrophic forces. It results in changes over some time.
- Sudden motions: As the name suggests, these are the visible motions, and includes significant landform changes like earthquakes and volcanic eruptions.
Slow Movements (Diastrophic forces)
In simple terms, Diastrophic forces can be defined as the pressure that is created due to the motion of the solid material on the earth’s surface. This includes all the processes that raise, move or build up the parts on the earth’s surface.
Diastrophism Involves the Following Processes:
- Epeirogenic motions: this is the process of warping or upliftment of large parts of the earth’s surface.
- Orogenic movements: this is essentially the process of mountain building that involves major folding, and affects the long as well as narrow belts of the surface.
- Earthquakes that occur due to relatively minor local movements.
- The horizontal motions of the crustal plates, or plate tectonics.
Diastrophic Forces can be Divided into Two Major movements.
- Orogenic movements
- Epeirogenic movements
Features of Horizontal Movements or Orogenic Movements
- These movements are caused by the horizontal pressure that acts on the surface of the earth from side to side.
- Orogenic movements or horizontal movements is also referred to as mountain building. They can be categorized into two major pressures such as the pressure of tension and pressure of compression.
- Orogenic motions create tension to the strata’s horizontal layer, which further leads to massive structural deformation of the earth’s surface.
Features of Vertical Movements or Epeirogenic Movements
- Epeirogenic movements are essentially responsible for the creation of plateaus and continents on earth.
- These powerful movements occur from the centre of the earth.
- Vertical movements can be responsible for both the upliftment as well as the subsidence of the continent.
- They cannot create variation in the horizontal rock strata unlike discussed in the previous type.
What are the Differences between Endogenic Forces and Exogenic Forces?
Let us now quickly discuss the major points of difference between Endogenic and exogenic forces:
Based on Origin
- Endogenic forces originate from within the surface of the earth.
- Exogenic or external forces are the pressure that occurs on or above the earth’s surface.
- Endogenic forces include earthquakes, mountain formation.
- Exogenic forces include the tidal force of the moon, erosion.
Nature of Movements
- Endogenic forces can result in both slow and/ or sudden motions.
- Exogenic forces will always lead to slow motions.
- Endogenic forces produce after-effects that are visible only after it causes sudden damage.
- Exogenic forces create changes visible over a period of thousands or millions of years.
Meaning of Important Terms You Must Know to Score Better on You Geography Paper
Following are some of the basic terms that one frequently encounters while preparing for the geography exam. Keep these notes handy for your future reference:
What is Erosion?
In geography, erosion is a term that indicates the action of processing of a surface that removes rock, soil or materials which are dissolved from one location to another location.
What are Lithospheric Plates?
The whole land part of the Earth is broken into a various number of plates. lithospheric plates refer to the blocks of the landmass.
What are Sand Dunes?
Sand dune refers to a large amount of windblown sand. This can be seen at the part of the beaches which are affected by tides.
Why do Plates Move?
To answer this question in the simplest form, the Earth’s surface plates’ motion happens due to the immense heat at the planet’s core. Molten rock in the mantle layer moves due to that immense heat.
Hope this article will help you in many ways while you prepare for the geography paper. So how do you plan to start the preparation? Let us know by commenting in the box below.