Meghan Knoth, Tatum Printy, Samantha DiIorio Volcanoes Meghan Knoth, Tatum Printy, Samantha DiIorio

What is a Volcano? A mountain that opens downward to a pool of molten rock below earth’s surface. Gases and rock shoot up through an opening and spill over with fragments of lava. Some eruptions were strong enough to knock down whole forests.

Why do Volcanoes Erupt? Earth’s crust is made of plates that fit together like a puzzle. These plates sometimes move; the friction of the plates movement is what causes the eruption of the volcano  this is called the theory of plate tectonics.

Plate Tectonics Theory When continents drift from place to place breaking apart, colliding, and grinding against one another. All plates are moving in different directions and different speeds.

How many Volcanoes are there? There are over 1,500 active volcanoes in the world. About 80 of these volcanoes are under water, such as oceans and large bodies of water.

Different Types of Volcanoes Cinder cones – are circular or oval cones made up of small fragments of lava from a single vent that have been blown into the air, cooled, and then fallen around the vent.

Composite Volcanoes Steep-sided volcanoes composed of many layers of volcanic rocks, usually composed of lava, rock, and ash Examples: Mt. Saint Helens and Mt. Rainier

Shield Volcanoes Shaped like a bowl or shield in the middle with long slopes made by lava flows. Lava flows from these volcanoes are called flood basalts.

The World’s Largest Volcano World’s largest, active volcano is Mauna Loa in Hawaii. There is famous coffee grown here. This volcano is 13,677 feet above sea level; from its base to its summit, it is taller than Mt. Everest.

Difference between lava and magma: Magma is liquid rock inside a volcano. Lava is a liquid rock (magma) that flows out of a volcano. Fresh lava grows red hot to white hot as it flows.

Why Lava takes a long time to cool: Lava cools slowly because lava is a poor conductor of heat. Lava flows slowly down and thickens as it hardens.