Volcanoes can be classified into three main types based on their frequency of eruption: 1) Active volcanoes are presently erupting or have erupted recently, 2) Dormant volcanoes are not currently erupting but may become active, and 3) Extinct volcanoes have not erupted for at least 10,000 years and are not expected to erupt in the future. Volcanic activity provides both benefits like fertile soils, mineral resources, and geothermal energy, as well as hazards such as air and water pollution, earthquakes, tsunamis, and destruction of life and property during eruptions.

2. INTRODUCTION
• Endogenic Forces : forces arising from interior of the earth.
• .Exogenic Forces : forces arising from the exterior of the earth

3. • A volcano is a vent (opening) in the earth’s crust from which hot molten rock (magma)
erupts from the earth’s interior.
• VOLCANOES Can be classified
• on various basis.
• Based on the frequency of eruption
they can be classified into
THREE Main types (groups) .
1. 1. ACTIVE
2. 2. DORMANT
3. 3. EXTINCT

4. Presently in active state and have erupted in recent past.
At present 550 … out of this 20 may erupt at any time..
EXAMPLES:
Mt.Stromboli in italy
Mt. Etna in Italy.
Barren Island ---- Andaman in India.

5. It is an active volcano that is not erupting recent times.
Also called sleeping volcanoes.
May become active at any time.
Very dangerous.
EXAMPLES
Mt. Mauna Kea in Hawaii Island.
Mt. killimanjaro in Africa.
Mt. Rainier in the United States(100years)

6.  These are not erupted in recent geological period(10,000years) .
The y have been inactive .
They are not likely to erupt
 (active) in future.
EXAMPLES
Mt. Kenya Africa..
Dhosi Hill Haryana in India.
The Bolshaya Udina in Russian Peninsula

7. 1. Fertile soils:
Weathered lava rocks and ash add to the soil fertility- Framing.
2. Minerals :
Volcanic rocks contain a number of metallic minerals.
Volcanic activity is also responsible for metamorphism of rocks and minerals.
Eg : Conversion of Carbon into diamond through volcanic activity.
3.Geothermal energy:
High level of heat due to volcanic activity help to generating geothermal energy.
It is a renewable energy.
4. Numerous types of landforms created by cooling and solidification of lava.
Eg.Volcanic plateaus,volcanic mountains,volcanic plains.,Coldera Lake

8. 5. Springs and geysers associated with volcanic areas contain mineral salt in
solution.This mineral water has medicinal value.
6. Promotes tourism
Volcanic activity adds to the
beauty of landscape.
Old faithful in theYellowstone Park
in U S A

10. 1. Destruction of life and property (economic loss)
2. Air pollution, environment pollution -many poisonous gases come out .
3. Water Pollution.
4. Lahars -steam from volcanic eruption may lead to heavy rainfall causing landslides,
mudflows and floods.
5. Earthquakes,Tusanamis
6. Climate change --Increase in temperature.
7. Agricultural land became unsuitable for cultivation.8. health hazards