What Are Causes of Volcanoes Erupting?
Other People Are Reading
-
Science Projects
-
The volcano science project is a classic that has been recreated each generation. The student typically builds a papier mâché model of a volcanic mountain. The student then combines substances, such as vinegar, lemon juice, hydrogen peroxide, baking soda, water, yeast and soap to produce a chemical reaction resembling a volcanic eruption. It is a mock eruption of imitation lava and steam.
Real Volcanoes
-
A real volcano is an opening on the earth's surface where eruptions of gases, rock fragments or lava can occur. Most volcanoes are mountains. Some of these volcanic mountains come up through the ocean and form islands. Over time, these eruptions can build up the land area around the opening, such as in the case of an island that has been created by a volcanic mountain. For example, over the years the land area of the Hawaiian Islands has been altered and expanded by volcanic activity.
-
Magma Forms
-
Scientists have developed theories as to how a volcano is formed and why one erupts. At the center of the earth's core it is very hot. It is so hot that rock melts and forms magma. Scientists believe most magma is formed some 50 to 100 feet beneath the earth's surface. When the rock inside the earth melts, it creates gasses that combine with the magma. When the magma fills with gas it begins to rise to the earth's surface. The reason it rises to the surface is that the mixture of magma and gas is lighter than the surrounding rock. On its movement to the surface, surrounding rock melts from the heat of the magma. This process creates a chamber called a "magma chamber." The magma chamber is the reservoir that holds the materials that will erupt from the volcano.
Eruptions
-
As the magma chamber fills with the gas-filled magma, pressure builds up. Weight from the solid rock surrounding the area contributes to the force of this pressure. When the magma pushes its way up to the surface, it breaks or weakens fractures in the surrounding solid rock. As the magma reaches the surface, gas is released and the magma blasts an opening through the earth's surface. The material that is pushed up helps to create the mountain that surrounds a volcano. Not all the magma or materials that are pushed up the magma chamber are expelled from the opening. Instead of reaching the surface it may escape through channels or remain underground.
-
Resources
- Photo Credit A. Johnson
