What is a stratovolcano simple definition?

Stratovolcanoes, also known as composite volcanoes, are conical volcanoes composed of multiple layers of intermediate to felsic lava, ash, and other volcanic debris.

What best describes a stratovolcano?

A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity.

What is a stratovolcano example?

Stratovolcanoes such as Mayon Volcano in the Philippines, Mount Momotombo in Nicaragua, and Ol Doinyo Lengai in Tanzania are steep cones built by both pyroclastic and lava-flow eruptions. The cone-shaped form slopes up gradually and becomes steeper (up to 35°) toward the summit, which generally contains a crater.

Does stratovolcano erupt?

Like shield volcanoes, stratovolcanoes are polygenetic; however, they differ from shield volcanoes in that they erupt infrequently, with typical repose intervals of hundreds of years between eruptions. Most active stratovolcanoes worldwide appear to be < 100,000 years old, although some, like Mt.

Why is it called a stratovolcano?

Stratovolcanoes are also called composite volcanoes because they are built of layers of alternating lava flow, ash and blocks of unmelted stone, according to the U.S. Geological Survey. Pressure builds in the magma chamber as gases, under immense heat and pressure, are dissolved in the liquid rock.

Are stratovolcanoes old?

Most active stratovolcanoes worldwide appear to be < 100,000 years old, although some, like Mt. Rainier, may be more than 1 million years old.

How does a stratovolcano erupt?

Stratovolcanoes can erupt with great violence. Pressure builds in the magma chamber as gases, under immense heat and pressure, are dissolved in the liquid rock.

What triggers a volcano to erupt?

Volcanoes erupt when molten rock called magma rises to the surface. As the magma rises, bubbles of gas form inside it. Runny magma erupts through openings or vents in the earth’s crust before flowing onto its surface as lava. If magma is thick, gas bubbles cannot easily escape and pressure builds up as the magma rises.

What happens after a stratovolcano erupts?

The pyroclastic material flung into the air, known as tephra, ranges in size from tiny dustlike particles – ash – to house-sized volcanic bombs. Eruption clouds may rise 25 or more miles into the atmosphere, and they can drop ash (as ashfall) hundreds or thousands of miles downwind.

What is the largest stratovolcano?

Mount Fuji is a stratovolcano. It is 3,776 meters tall.

Is a stratovolcano a shield volcano?

Stratovolcanoes have relatively steep sides and are more cone-shaped than shield volcanoes. The lava therefore builds up around the vent forming a volcano with steep sides. Stratovolcanoes are more likely to produce explosive eruptions due to gas building up in the viscous magma.

Why are stratovolcanoes so tall?

They are larger than cinder cones, rising up to 8,000 feet (2,438 meters). Stratovolcanoes result from a conduit system of vents leading from a magma reservoir beneath the surface. When dormant, they typically have steep concave sides that sweep together at the top around a relatively small crater.

Is there another word for stratovolcano?

A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra.

Eruption. The eruption of a stratovolcano begins when a central vent emits pyroclastic material and lava. This will usually happen as an explosion of gases, unlike a Hawaiian volcano, in which lavas seem to flow like thick water. When an explosion occurs, rock and debris are ejected into the air.

How are stratovolcanoes formed?

A stratovolcano is a tall volcano shaped like a cone, formed by various layers of materials such as volcanic ash, hardened lava, pumice, and tephra. Stratovolcanoes are steep and have periodic explosive and effusive eruptions, although some have calderas, which are collapsed craters.

Is Krakatoa a stratovolcano?

Mount Krakatoa is an example of a stratovolcano, a tall, conical volcano with multiple strata of solidified lava , tephra , as well as volcanic ash.