Parts of a Volcano

The accumulation of lava, ash, and rocks on a hot spot due to successive eruptions forms a conical structure called cone. The smallest cones are called conelets and are usually formed in the area near the main cone.

The bowl-shaped depression around the opening at the top of the volcano is known as the crater. Some volcanoes have broad craters called calderas, which are formed due to explosive eruptions. The opening from which volcanic materials, such as lava, ash, and gases, are expelled is called the vent. It is usually found in the middle of the crater. Below the vent is the pipe, which serves as the passageway of all volcanic and pyroplastic materials. The pipe leads down the magma chamber.

Sometimes, mature volcanoes emit materials from the breaks and fissures that develop along their bases. Continued volcanic activity produces small cones from these fissures, such as fumaroles. Fumaroles are volcanic openings that release steam or sulfuric gases. The steam coming out of fumaroles can be used to generate geothermal energy. Examples of fumaroles are the secondary vents of Mt. Etna in Italy.