For billions of years there has been a slow but continuous displacement of the plates that form the crust of our planet Earth.
This movement originates from the call Tectonic plates, a theory that complements and explains the Continental drift.
The continents unite with each other or fragment, the oceans open, mountains rise, the climate changes, influencing all this, in a very important way in the evolution and development of living beings. New crust is created on the seabed, crust is destroyed in the ocean trenches and they are produced collisions between continents that modify the relief.
The basis of the theory
According to the theory of plate tectonics, the earth's crust is composed of at least a dozen rigid plates that move in its air. These blocks rest on a layer of hot and flexible rock, called an asthenosphere, which flows slowly as a hot tar.
Geologists have not yet determined exactly how these two layers interact, but the most avant-garde theories claim that the movement of the thick and molten material of the asthenosphere forces the upper plates to move, sink or rise.
The basic concept of the theory of Tectonic plates It's simple: the heat rises. Hot air rises above cold air and hot water flows float above those of cold water.
The same principle applies to hot rocks that are under the earth's surface: the molten material of the asthenosphere, or magma, rises upwards, while the cold and hardened matter sinks deeper and deeper into the bottom, inside the mantle.
The sinking rock finally reaches the high temperatures of the lower asthenosphere, heats up and begins to rise again.
This continuous movement and, in a certain circular way, is called convection. At the edges of the divergent plate and in the hot areas of the solid lithosphere, the molten material flows to the surface, forming a new crust.
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