Volcanoes and their effects on Earth EQ: How do volcanoes effect Earth’s surface?

Volcanoes and their effects on Earth

EQ: How do volcanoes effect Earth’s surface?

What is a Volcano?• A volcano is a mountain that forms

when molten rock, magma, is forced to the Earth’s surface

What are the types of Volcanic eruptions?

Nonexplosive Eruptions:

• Continuous flow of lava

• Can release huge amounts of molten rock

• Can have lava fountains can spray lava into the air

Explosive Eruptions:• Clouds of hot

debris and gases shoot out from the volcano, often at supersonic speeds

• The molten rock hardens in the air creating dust particles

• Can demolish rock formations

What are the types of Volcanoes?

• There are three types of Volcanoes:– Shield: spreads out and covers a wide area– Cinder cone: cone shaped with a narrow

base and dome opening– Composite: most common with broad

bases and steep slopes

Where do Volcanoes form?• Volcanoes form on or

near plate boundaries

• They are usually occur at convergent and divergent boundaries

• The plate boundary surrounding the Pacific Ocean have so many volcanoes that it is known as the Ring of Fire

• 75% of the world’s volcanoes are found in the Ring of Fire

What are the effects of Volcanoes?

Climate Changes:• In large eruptions,

volcanic ash and gases can reach the upper atmosphere

• If there is enough ash, it can block sunlight causing temperature drops

• This can result in climate changes all over the world

What are the effects of Volcanoes?

Earth’s Surface:• Volcanic ash can cause great

damage to surrounding trees and vegetation

• It can flow like an avalanche, choking and searing everything in its path

• Large amounts of ash can cause buildings to collapse under the extreme weight

• Can dam up rivers, resulting in massive flooding