Presentation on theme: "Volcanoes and their effects on Earth"— Presentation transcript:
1Volcanoes and their effects on Earth EQ: How do volcanoes effect Earth’s surface?
2What is a Volcano?A volcano is a mountain that forms when molten rock, magma, is forced to the Earth’s surface
3What are the types of Volcanic eruptions? Nonexplosive Eruptions:Continuous flow of lavaCan release huge amounts of molten rockCan have lava fountains can spray lava into the airExplosive Eruptions:Clouds of hot debris and gases shoot out from the volcano, often at supersonic speedsThe molten rock hardens in the air creating dust particlesCan demolish rock formations
4What are the types of Volcanoes? There are three types of Volcanoes:Shield: spreads out and covers a wide areaCinder cone: cone shaped with a narrow base and dome openingComposite: most common with broad bases and steep slopes
5Where do Volcanoes form? Volcanoes form on or near plate boundariesThey are usually occur at convergent and divergent boundariesThe plate boundary surrounding the Pacific Ocean have so many volcanoes that it is known as the Ring of Fire75% of the world’s volcanoes are found in the Ring of Fire
6What are the effects of Volcanoes? Climate Changes:In large eruptions, volcanic ash and gases can reach the upper atmosphereIf there is enough ash, it can block sunlight causing temperature dropsThis can result in climate changes all over the world
7What are the effects of Volcanoes? Earth’s Surface:Volcanic ash can cause great damage to surrounding trees and vegetationIt can flow like an avalanche, choking and searing everything in its pathLarge amounts of ash can cause buildings to collapse under the extreme weightCan dam up rivers, resulting in massive flooding