What are the characteristics of a composite volcano?
The characteristics of composite volcanoes, also known as stratovolcanoes, are:
- cone shape with steep sides
- made of layers of hardened cinder, lava and ash
- most violent eruptions of all volcano types
- high altitudes (up to 8,000 ft.)
- erupts from one large vent or a clustered group of vents in a summit crater
- easily eroded by the wind when dormant
- built up over hundreds of years
How do you describe a composite volcano?
Composite volcanoes have the following characteristics:
- Acidic lava, which is very viscous (sticky).
- Steep sides as the lava doesn’t flow very far before it solidifies.
- Alternate layers of ash and lava. For this reason, they’re also known as stratovolcanoes .
- Violent eruptions.
- Longer periods between eruptions. How tall is a composite volcano? ...
Which is the best description of a composite volcano?
Composite Volcano (Stratovolcano): Key Facts and Formation
- Composition. Composite volcanoes—also called stratovolcanoes—are named for their composition. ...
- Formation. Stratovolcanoes form at subduction zones, where one plate at a tectonic boundary is pushed below another.
- Location. ...
- Eruptions and Their Consequences. ...
- Sources. ...
What is the definition of a composite volcano?
Composite volcanoes, also called stratovolcanoes, are cone-shaped volcanoes built from many layers of lava, pumice, ash, and tephra. Because they are built of layers of viscous material, rather than fluid lava, composite volcanoes tend to form tall peaks rather than rounded cones. See also What do birds see when they look at humans?
Do composite volcanoes have lava flows?
Some of the Earth's grandest mountains are composite volcanoes--sometimes called stratovolcanoes. They are typically steep-sided, symmetrical cones of large dimension built of alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs and may rise as much as 8,000 feet above their bases.
What type of lava and magma are found in composite volcanoes?
Composite volcano magma is felsic, which means it contains silicate-rich minerals rhyolite, andesite, and dacite. Low-viscosity lava from a shield volcano, such as might be found in Hawaii, flows from fissures and spreads.
Does a composite volcano have sticky lava?
Composite volcanoes: steep slopes; thick, sticky lava; lava does not flow quickly or far; erupt violently.
What type of eruptions do composite volcanoes have?
Composite Volcanoes The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava. A pyroclastic flow is a superheated mixture of hot steam, ash, rock and dust. A pyroclastic flow can travel down the side of a volcano at very high speeds with temperatures over 400 degrees celsius.
What are 3 facts about composite volcanoes?
Composite volcanoes are one of the most dangerous types of volcanoes. A composite volcano is also known as a stratovolcano. It has steep sides which makes it quite tall. There are many kinds of volcanoes: submarine volcanoes, shield volcanoes, cinder cones, dome volcanoes, and composite volcanoes.
How do you describe a composite volcano?
A composite volcano, also known as a stratovolcano is a cone-shaped volcano built from several layers of lava, pumice, ash, and tephra. Due to its viscous lava, a composite volcano tends to form tall peaks rather than rounded cones. Mount Fuji in Japan and Mount Shasta in California are examples of composite volcanoes.
What is a lava flow called?
'A'a lava flows are also called clinkers, because of their rough and jagged appearance. The eruptions of submarine volcanoes result in pillow lavas, which form as the lava cools in seawater.
What is viscous lava?
Lava viscosity determines the kind of volcanic activity that takes place when the lava is erupted. The greater the viscosity, the greater the tendency for eruptions to be explosive rather than effusive.
Why are composite volcanoes more explosive?
Composite volcanoes have the following characteristics: Andesitic magma, which is lower in temperature, has more silica and a lot of dissolved gases and is more likely to explode when it reaches the surface. Acidic lava, which is very viscous (sticky). Steep sides as the lava doesn't flow very far before it solidifies.
What type of volcanoes are formed from viscous or sticky lava that does not flow easily?
Stratovolcano. Stratovolcanoes have relatively steep sides and are more cone-shaped than shield volcanoes. They are formed from viscous, sticky lava that does not flow easily.
What happens when a composite volcano erupts?
Composite volcanoes have very sticky and thick lava, which can make them very explosive when they erupt: gas bubbles that are trapped in the magma chamber find it hard to escape through the viscous rock. They can also spurt lots of hot ash and rocks into the air, making them extremely dangerous.
How does a composite volcano erupt?
Composite volcanoes are fed by a conduit system which taps into a reservoir of magma deep within the Earth. This magma can erupt out of several vents across the composite volcano's flanks, or from a large central crater at the summit of the volcano.
Which type of volcano has felsic lava?
Composite volcanoesComposite volcanoes are constructed of felsic to intermediate rock. The viscosity of the lava means that eruptions at these volcanoes are often explosive.
Are composite volcanoes basaltic?
Shield volcanoes are formed by basaltic magma, typically above a mantle plume, whereas the stratovolcanoes (sometimes referred to as composite volcanoes) are formed by andesitic/rhyolitic magma.
What type of volcanoes are formed from viscous and sticky lava that does not flow easily?
Stratovolcano. Stratovolcanoes have relatively steep sides and are more cone-shaped than shield volcanoes. They are formed from viscous, sticky lava that does not flow easily.
Which type of lava erupts from shield volcanoes?
basaltShield volcanoes are usually basalt but can be constructed of mostly andesitic lava flows. Mauna Loa and Kīlauea erupt almost exclusively basaltic lavas.
Why do volcanoes form cones?
The volcanoes form steep cones, rather than rounded shapes, because the magma is viscous. Composite volcano magma is felsic, which means it contains silicate-rich minerals rhyolite, andesite, and dacite. Low-viscosity lava from a shield volcano, such as might be found in Hawaii, flows from fissures and spreads.
How many people have died from volcanoes since 1600?
Lahars are basically volcanic landslides down the steep slope, traveling so quickly that they are difficult to escape. Nearly a third of a million people have been killed by volcanoes since 1600. Most of these deaths are attributed to stratovolcanic eruptions. Semeru Volcano in Indonesia is an active stratovolcano.
Why do composite volcanoes have tall peaks?
Because they are built of layers of viscous material, rather than fluid lava, composite volcanoes tend to form tall peaks rather than rounded cones. Sometimes the summit crater collapses to form a caldera.
What are some examples of composite volcanoes?
Famous examples of composite volcanoes include Mount Fuji in Japan, Mount Rainier and Mount St. Helens in Wash ington State, and Mayon Volcano in the Philippines.
Which type of volcano is responsible for the most catastrophic eruptions in history?
Composite volcanoes are responsible for the most catastrophic eruptions in history.
What are the different types of volcanoes?
There are several different types of volcanoes, including shield volcanoes, composite volcanoes, dome volcanoes, and cinder cones. However, if you ask a child to draw a volcano, you'll almost always get a picture of a composite volcano.
Where are composite volcanoes found?
To date, composite volcanoes have only been found on one other body in the solar system: Mars. Zephyria Tholus on Mars is believed to be an extinct stratovolcano.