Relief is the variations in elevation of the Earth’s surface. These variations are founded in the surface of our continents and on the ocean bed.
It is formed by:
-The theory of plate tectonics explain that Earth’s crust is made up of plates which float on the top layer of the mantle.
-Rifts are formed when the plates separate. When magma cools, is formed a new crust.
-The area where the crust is destroyed is called a subduction zone.
-Magma pushes up through the continental crust, creating volcanoes on the Earth’s surface.
-Two continental plates sometimes collide and the pressure forms folds. Faults occur when the crust is rigid and fractures.
-Erosion of rocks, fragment or dissolved.
-Transport of the eroded materials.
-Sedimentation, or the deposition of materials in another place. The erosion of rocks is caused by the interaction of external agents over an extended period of time. These forces are mainly water, wind, Temperature.
EXAMPLES: -The action of water dissolves the limestone and gypsum and they form karstic relief. – The scree of mountains are accumulations of rocks which originated in this way.