Question

What is volcano? explain the distribution of volcanoes in the world

Answer 1

A volcano is a mountain that opens downward to a pool of molten rock below the surface of the earth. When pressure builds up, eruptions occur. Gases and rock shoot up through the opening and spill over or fill the air with lava fragments .
These belts coincide with major lines of weakness is the earth's crust and these happen to be the earthquake zones also. These weaker zones are also characterised by the young folded mountains.
There are three volcanic belts, besides many volcanoes which are outside these belts. The three volcanic belts are as under:

1. The Circum-Pacific belt

2. The Mid-Continental belt

3. The Mid-Atlantic belt.

Answer 2

Volcano and its distribution

Explanation:

Volcanoes refer to a vent or fissure on the earth's surface from which lava comes out.It emits gases, molten lava and vast quantities of pyroclastic deposits.

Distribution of volcanoes around the world is as follows:-

• There are about 800 active volcanoes around the earth's surface.

• Also, there are thousands of volcanoes that are extinct volcanoes  of which most of them are present under the sea floor.

• A great majority of volcanoes are found to be concentrated along the following belts:-

1. The Circum Pacific Belt
2. The Alpine Indonesian Belt
3. The Mid-Oceanic Ridges
4. African Rift Valleys

• The belt along the Pacific ocean contains the largest number of active volcanoes and thereore it is called the "ring of fire".
• The Circum Pacific and the Alpine Indonesian belt are the regions of crustal deformation which lie along the collision edges of the crustal plates.
• Similarly, the Mid-Oceanic ridges and the African rift valleys represent big tensional cracks on the earth's surface.