Endogenic Forces: Sources & Geological Impact

Endogenic forces are geological processes that originate from within the Earth’s interior. These forces shape the Earth’s surface by causing movements and deformations of the Earth’s crust. These processes are responsible for creating and shaping landforms such as mountains, valleys, and plateaus over millions of years. They play a crucial role in shaping the Earth’s landscape and are a key aspect of understanding geological phenomena.

Energy Sources Behind Endogenic Geomorphic Forces

• Source: Endogenic forces occur due to the energy emanating from within the earth’s surface.
  • Sources of this energy include radioactivity, rotational and tidal friction, and primordial heat from the Earth’s formation.
• Effect of Geothermal Gradients:  Geothermal gradients along with heat flow within the Earth’s interior cause diastrophism (deformation of the Earth’s crust) and volcanism.
  • Variations in geothermal gradients and heat flow result in differences in crustal thickness and strength.
  • Thus, the action of endogenic forces is inconsistent, leading to an uneven distribution of tectonically controlled crystal surfaces.

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Diastrophism

• Diastrophism: It includes processes causing slow movement, elevation or building up portions of the Earth’s crust. It is also known as land-building forces.  It can cause different types of movements,
  • Warping: bending of the Earth’s crust, 
  • Folding: bending of rock layers
  • Faulting: breaking and displacement of rock layers
  • Uplifting or subsiding of the Earth’s crust. 
  • Diastrophism is of two types: Orogenic and Epeirogenic
• Orogenic Process:  It involves mountain building through severe folding and affects long and narrow belts of the earth’s crust. 
  • The crust undergoes significant deformation, forming folds.
  • Divergent Force: Orogenic forces operate in a horizontal manner (tangential forces).
    • It is also called tensional force when it operates in opposite directions and creates ruptures, fractures, cracks, and faults in the crustal parts.
  • Convergent Forces: When forces operate towards each other face to face, they are also called compressional forces.
• Epeirogenic Process: This process involves upliftment (emergence) and subsidence (submergence) of large parts of the earth’s crust (continental masses) through vertical upward and downward movements. 
  • It is a continental building process. 
  • There may be simple deformation.
• Metamorphism: Both orogenic and epeirogenic processes lead to changes in pressure, volume, and temperature (PVT), which in turn trigger the metamorphism of rocks.
• Sudden Endogenic Processes: Sudden movements are caused by sudden endogenic forces originating deep within the Earth. It includes earthquakes, volcanism, and landslides. 

Conclusion

Endogenic forces, powered by energy from within the Earth, shape our planet’s surface through processes like volcanism and crustal deformation. These forces result in the formation of mountains, valleys, and other geological features, playing a vital role in shaping the Earth’s landscape over time.