Volcanoes

By: Mr. Anderson

What is a volcano?A volcano is a mountain that opens downward to a pool of molten rock below the surface of the earth.

When pressure builds up, an eruption occurs!!!

What is an Eruption?An eruption is when molten rock, gases, steam, and lava are ejected out of a volcano.

These eruptions can cause:Earthquakes

Mudslides

Flash floods and more!

What is lava? What is Magma? What’s the difference?Lava- Lava is liquid rock that flows out of the volcano. It glows red hot and changes to white as it goes

Magma- Liquid rock inside the volcano

Magma is inside the volcano and Lava is outside the volcano!

How are Volcanoes formed?1.Magma from the Earth’s mantle is pushed up to the surface

2.At the surface it erupts and turns into lava

3. Lava flows out and ash is put into the air

4. The more a volcano erupts, the bigger it gets!!

The lava cools and continues to form layers on top of itself. SUPER NEAT :)

3 stages of VolcanoesDormant

Extinct

Active

Active VolcanoAn active volcano is one which has recently erupted and there is a possibility that it may erupt soon

Dormant VolcanoA dormant volcano is one which has not erupted in a long time but there is a possibility it can erupt in the future.

Extinct Volcano

An extinct volcano is one which has erupted thousands of years ago and there’s no possibility of eruption.

Why do Volcanoes Erupt?The Earth’s crust is made up of huge slabs or plates and they fit together like a puzzle

When these plates try to move, they cause friction.

This friction causes earthquakes and volcanic eruptions near the edges or fault areas!!!

What is the name of this theory?????

What is plate Tectonics?A theory that the continents drift or move from place to place

They: break apart, collide, and grind against each other.

4 types of VolcanoesCinder Cones

Composite Shield

Lava Volcanoes

Cinder ConesCircular or oval cones

small/single vent in the crustFragments cool and fall around the vent

Composite VolcanoesSteep-sided

Many layers of volcanic rockMade from lava, ash, and rock debris

Shield Volcano

shaped like a bowl or shield in the middlelong gentle slopes made by balastic flow

Lava Volcanoes

The domes are made when lava erupting is to thicksteep sided mounds of lava pile up near the vent

Pyroclastic FlowsA fast

movement of fluidized

mixture that contains gas and rocks.

Ring of Fire

String of volcanoesand sites of seismic activities

This area has lots of Earthquakes and Volcanic Eruptions

Around edges of Pacific Ocean