Formation of Volcanoes
Formation of Volcanoes | Volcanoes form where Collision of Tectonic Plates occur
We have to know the inner structure of Earth, to know well about the formation of volcanoes. Earth on which we live can be divided into four layers based on extent of depth. Uppermost layer called Crust extends to a depth of 15 kilometers. Layer which lies at a depth of 2900 kilometers is called Mantel. The Outer Core layer lies at a depth of 5000 kilometers. Inner core layer lies at a depth of 6,300 kilometers. There will be Maho Gutenberg Discontinuity between the Crust and Mantel & also between the layers Mantel and Inner core. That means upper layers of Earth are floating on the lower layers. Another main thing is the existence of top layer Crust in divided form of 12 big pieces. These are called Tectonic plates. These plates collide and push each other continuously. Volcano is formed at the region where the collision of two Tectonic plates occurs. When one of the two plates got slide down the other plate, then the magma of Mantel layer get settled down at the empty space. After sometime, due to the tension in the crust, magma comes out at the weakest regions on the Earth. These are called Volcanoes.
Due to extreme heat, the stones get dissolved resulting in Magma. It is the composite mixture form of liquid, solid and gaseous forms. Magma inside the Earth accumulates at some region inside due to the tension in the upper layer. These regions are called volcanic regions. The accumulated magma comes as a huge burst and is called as lava.
Temperature of the magma varies with regions. It lies from 700 degrees to 1300 degrees centigrade. Silica i.e. glass is the main component of Magma. Along with it, some types of gases are settled in it in the form of bubbles.