Magma

Magma is molten rock that is deep underground within the Earth's mantle and portions on the crust called magma chambers. Click on image for full size (31K GIF ) Courtesy of Boise National Forest

If you could travel to the center of the Earth, you would find that it gets hotter and hotter as you travel deeper. The heat is naturally produced by decay of radioactive elements. Within the Earth’s mantle layer it is hot enough that much of the rock is molten. The molten rock is called magma. Magma is so hot that it glows white and is so bright that you’d need sunglasses to look at it! If it flows into an area underground that is less hot, it cools, becomes yellow, and then increasingly deeper shades of red. As it cools slowly, minerals crystallize from the melt forming intrusive igneous rocks like granite.

If magma finds a crack in the Earth and comes to the surface, it is called lava and cools to form extrusive igneous rocks like basalt.

Magmas can be different depending on their chemical composition. Magma is a mixture of elements such as silica, oxygen, iron, sodium, and potassium and not all magmas have the same amounts of each element. As the molten material cools, elements combine to form the common types of silicate minerals, which are the building blocks of igneous rocks. Rocks that form from different types of magma are often made of different minerals.

Magma is molten rock that is deep underground. Click on image for full size (31K GIF) Courtesy of Boise National Forest

If you could travel to the center of the Earth, you would find that it gets hotter and hotter as you travel deeper. The heat is naturally produced when radioactive elements break apart. Within the Earth’s mantle layer it is hot enough that much of the rock has melted, turning it into a liquid that we call molten rock.The molten rock is called magma. Magma is so hot that it glows white and is so bright that you’d need sunglasses to look at it! If it flows into an area underground that is less hot, it cools, becomes yellow, and then increasingly deeper shades of red. As it cools slowly, minerals crystallize from the melt forming intrusive igneous rocks like granite.

If magma finds a crack in the Earth and comes to the surface, it is called lava and cools to form extrusive igneous rocks like basalt.

Magma is molten rock that is deep underground. Click on image for full size (31K GIF) Courtesy of Boise National Forest

Pretend that you are an explorer traveling to the center of the Earth. You would find that the deeper you travel, the hotter it gets! Beneath the crust, in the mantle layer, it is hot enough that rock can melt. When rock melts and turns into a liquid, we call it "molten". The molten rock is called magma. Magma is so hot that it glows bright white. You would need sunglasses to look at it!

If magma flows into an area underground that is less hot, it cools, becomes yellow, and then red. As it cools slowly, minerals form crystals making a plutonic rock like granite.

If magma finds a crack in the Earth and comes to the surface, it is called lava!