In a weaker part of the earth’s crust sometimes the molten rock finds its way to the surface and is poured out to form a volcano. Thus the spewing out of molten material, ash, gases, etc. through vents is called a volcanic eruption. The magma which comes out on the surface is called lava.
Volcanoes are of three types:
Those volcanoes are called active which erupt regularly. Mount Etna in Sicily and Barren Island in Andamans are the examples of active volcanoes.
Those volcanoes are called dormant which have not erupted for a long time but they can erupt in the future, Mount Fuji in Japan and Mount Shasta in the USA are the examples of dormant volcano.
Extinct or dead volcano: Those volcanoes are called extinct or dead which have not erupted for several hundred of years and there Is no hope of volcanic eruption In the future, Mount Kilimanjaro In Tanzania Is an extinct volcano.
1. Which region of the earth experiences volcanic eruption frequently?
Ans. Pacific Ocean.
2. What is a vent?
Ans. Vent is an op
3. What Is a crater?
Ans. The top of the vent has a cup like depression which If known as a crater.
4. What is a caldera?
Ans. Due to frequent volcanic eruption, the crater become larger and larger, Such a large crater Is known as caldera,
5. Where is the active volcano Krakatua situated?
Ans. In Indonesia.