Volcanic Landforms

Landforms From Lava and Ash Rock and other materials formed from lava create a variety of landforms including shield volcanoes, composite volcanoes, cinder cone volcanoes, and lava plateaus.

Shield Volcanoes A wide gently sloping mountain made of layers of lava and formed by quiet eruptions. Shield volcanoes rising from a hot spot on the ocean floor created the Hawaiian Islands.

Cinder Cone Volcanoes A steep cone shaped hill or mountain. Cinder cone volcanoes occur from pile up of cinders, bombs, and ash from an explosive volcano.

Composite Volcano Tall, cone shaped mountains in which layers of lava alternate with layers of ash. Examples: Mt. Saint Helens, Mt. Fuji

Lava Plateau High level areas formed from lava Example: Columbia Plateau Caldera: A huge hole left by the collapse of a volcanic mountain. The hole is filled with the pieces of the volcano that have fallen inward as well as some lava and ash.

Soils from lava and ash Soils made from volcanic ash is some of the richest soil in the world. Volcanic ash breaks down and releases potassium, phosphorus, and other materials that plants need. People settle near volcanoes to take advantage of the fertile soil.

Landforms from Magma Features formed from magma include: volcanic necks, dikes, and sills, as well as batholiths and dome mountains. Volcanic necks, dikes, and sills: A neck forms when magma hardens in a volcanoes pipe. Magma that forces itself across rock layers hardens into a dike.

When magma squeezes between layers of rock it is called a sill. Batholiths: A mass of rock formed when a large body of magma cools inside the crust. Dome Mountains: Forms when rising magma is blocked by horizontal layers of rock. The magma forces the layers of rock to bend upward into a dome shape