A volcanic mountain starts out as a simple crack in the Earth called a volcanic vent. Magma erupts out of the ground as lava flows, clouds of ash, and explosions of rock. This material falls back to Earth around the vent, and piles up around it. Over time (and sometimes quite quickly) a volcanic mountain builds up, with the familiar cone shape.
Characteristics of volcanic mountains
- A magma chamber is a hollow space inside the earth surface. The molten rocks are called magma. It is present just below the vent of the volcano and is a source of lava.
- Magma chamber contains molten rocks and gases under high pressure. Conduit is a pipe-like structure through which magma comes out and it opens into the main vent. The depth of the magma chamber is usually 1km to 10 km.
- Lava is the molten rock or magma that comes through a volcanic vent. It generally consists of silicates or silica rocks and is in liquid or semi-solid form. The temperature of lava is anywhere between 700 0 C to 12000
- Lava cools and hardens after coming into contact with the air. This cooled lava forms a volcanic mountain-like shape.
- A vent is a hole in the earth’s surface through which the lava comes out with great pressure. Generally vent is a weak point on the crust of the earth. There could be more than one vents of a volcanic mountain.
- Craters are the circular depressions around the main vent. Craters are developed due to a large explosion in the volcano. These are formed when the magma chamber is present near the vent.
- The volcano becomes active due to the creation of high pressure in the magma chamber. Generally, the magma chamber contains a large amount of water which is continuously converting into steam because of the geothermal energy. When the pressure becomes so high, it comes out as an explosion causing a volcanic eruption.
- A pyroclastic flow is the flow of molten semi-liquid lava away from the volcanic mountain, downhill.
Characteristics Of Volcanic Mountains
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