7/31/2019 | National Geographic Society

R E S O U R C E L I B R A R Y | E N C Y C L O P E D I C E N T RY Volcanic Cone

A volcanic cone is the hill-shaped that forms around a . Volcanic cones can be steep or gently sloping depending on the type of eruption that form them.

For the complete encyclopedic entry with media resources, visit: http://www.nationalgeographic.org/encyclopedia/volcanic-cone/ A volcanic cone is a hill-shaped landform that forms around a volcano. Volcanic cones can be steep or gently sloping depending on the type of eruption that forms them.

The steepest cones form around . Cinder cones form from ash and cinders--partly-burned, solid pieces of magma, that fall to the ground following a volcanic eruption. This type of eruption contains little , as the magma hardens and breaks into pieces during the explosion. As a result, cinder cone volcanoes tend to be smaller than other types of volcanoes. Italy’s Mt. Vesuvius is a famous cinder cone volcano.

In contrast, shield volcanoes are characterized by a large, broad cone with sides sloping gently away from the center. The lava that erupts from these volcanoes is a thin liquid that slowly emerges from the center of the volcano as well as from cracks in its sides. The lava spreads in a thin layer before cooling. ’s is a famous example of a shield cone volcano.

A third type of volcanic cone is a composite cone. Composite cone volcanoes are also called stratovolcanoes. They form when different types of eruptions deposit different materials around the sides of a volcano. Alternating eruptions of and lava cause layers to form. Over time these layers build up. The result is a cone that has a gentler slope than a cinder cone but is steeper than a . Washington state’s Mt. St. Helens is an example of a composite cone volcano.

Vocabulary https://www.nationalgeographic.org/encyclopedia/volcanic-cone/print/ 1/2 7/31/2019 Part of Volcanic Cone | National Geographic Society Term Definition Speech hill created by tiny bits of lava blown out of a volcano and fallen down cinder cone noun around the volcanic vent. Also called a cone. eruption noun release of material from an opening in the Earth's crust. Mount St. noun active volcano in the U.S. state of Washington. (2,549 meters/8,364 feet) Helens Mount noun active volcano in southwest Italy. (1,190 meters/3,900 feet) Vesuvius shield noun large, gently sloping volcano made from fluid lava. volcano steep volcano made of hardened lava, rock, and ash. Also known as a stratovolcanonoun composite volcano. volcanic ash noun fragments of lava less than 2 millimeters across. volcanic cone noun hill created by a volcanic eruption.

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