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Stratovolcano facts for kids

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Cono de Arita, Salta. (Argentina)
Cono de Arita, a stratovolcano in Salta (Argentina)
FujiSunriseKawaguchiko2025WP
Mount Fuji, an active stratovolcano in Japan that last erupted in 1707–08
Tavurvur volcano edit
Tavurvur, an active stratovolcano in Papua New Guinea

A stratovolcano is a tall, conical volcano built up by many layers (strata) of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes have a steep slope and explosive eruptions every now and then.

Stratovolcanoes are common along plate tectonic boundaries where oceanic crust is drawn under continental crust.

Hazards

Etna from 2900m
Mount Etna on the island of Sicily, in southern Italy
Ashfall from Pinatubo, 1991
Snow-like blanket of Mount Pinatubo's ashfall deposits in a parking lot on Clark Air Base (June 15, 1991)

In addition to potentially affecting the climate, volcanic clouds from explosive eruptions pose a serious hazard to aviation.

Mayon 0052
Mayon Volcano in Philippines extruding lava flows during its eruption on December 29, 2009

Lava flows from stratovolcanoes are generally not a significant threat to humans or animals because the highly viscous lava moves slowly enough for everyone to flee away from the path of flow. The lava flows are more of a threat to property. However, not all stratovolcanoes erupt viscous and sticky lava. Nyiragongo, near Lake Kivu in central Africa, is very dangerous because its magma has an unusually low silica content, making it quite fluid.

Volcanic bombs are extrusive igneous rocks ranging from the size of books to small cars, that are explosively ejected from stratovolcanoes during their climactic eruptive phases. These "bombs" can travel over 20 km (12 mi) away from the volcano, and present a risk to buildings and living beings while shooting at very high speeds (hundreds of kilometers/miles per hour) through the air. Most bombs do not themselves explode on impact, but rather carry enough force to have destructive effects as if they exploded.

Lahars (from a Javanese term for volcanic mudflows) are mixtures of volcanic debris and water. Lahars usually come from two sources: rainfall or the melting of snow and ice by hot volcanic elements, such as lava. Depending on the proportion and temperature of water to volcanic material, lahars can range from thick, gooey flows that have the consistency of wet concrete to fast-flowing, soupy floods. As lahars flood down the steep sides of stratovolcanoes, they have the strength and speed to flatten or drown everything in their paths.

List of stratovolcanoes in North America

Mount Rainier over Tacoma
Northwest side of Mount Rainier seen from Tacoma
Pyroclastic and Cayley
The Mount Cayley volcanic complex on August 13, 2005. Summits left to right are Pyroclastic Peak and Mount Cayley.
Mount Adams 3503s
Mount Hood 2619s
Mount Hood, 2017

Canada

Northwest Territories/Nunavut
Northern British Columbia
Southern British Columbia

Mexico

United States

Alaska
Washington
Oregon
California
Arizona
New Mexico

Related pages

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See also

Kids robot.svg In Spanish: Estratovolcán para niños

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Stratovolcano Facts for Kids. Kiddle Encyclopedia.