Configuration of earth is the result of various processes operating within as well as outside the earth. Multiple forces affect the earth’s crust.
ENDOGENETIC FORCES (LAND BUILDING FORCES)
- They are called as internal forces as they are present within Earth.
- These lead to vertical and horizontal movements and result in subsidence, land upliftment, volcanism, faulting, folding, earthquakes, etc.
- Primordial heat, radioactivity, tidal and rotational friction from the earth results in the creation of these forces.
- Diastrophic forces are slow movements. It involves epeirogenetic and orogenetic movements.
- Epeirogenetic movements are the vertical forces and are responsible for continent building. These vertical movements can lead to submergence as well as emergence.
- Orogenetic movements are the horizontal forces and are responsible for mountain building. They can be categorized into two major pressures such as the pressure of tension and pressure of compression.
- Catastrophic forces are fast movements like earthquakes.
EXOGENETIC FORCES (LAND MODIFYING FORCES)
- They are forces acting outside the earth. Hence, are called as external forces.
- They are land modifying forces because they cause land to wear down because of their action. Therefore, they are referred to as land wearing forces/denudational forces.
- Exogenic processes include weathering, mass wasting, erosion, and deposition.
- Geomorphic agents are natural elements capable of performing these exogenic processes (or exogenic geomorphic agents). For example, the wind, water, and waves.
- They draw their power from the solar energy.
