What type of lava does a composite volcano have?

Acidic lavaAcidic 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.

What type of lava flow does a composite volcano have?

Stratovolcanoes show interlayering of lava flows and typically up to 50 percent pyroclastic material, which is why they are sometimes called composite volcanoes. Pyroclastic flows are high-density mixtures of hot, dry rock fragments and hot gases that move away from the vent that erupted them at high speeds.

What is composite volcanoes lava made of?

Magma Composition

Composite volcanoes usually erupt a range of compositions from basalt to rhyolite, but intermediate (andesitic) and dacitic magmas are most common. Mount Rainier has less compositional diversity than many composite cones as it consists of mostly andesitic lava flows and lahar deposits.

Do composite volcanoes have thick lava?

Composite volcanoes are also called stratovolcanoes because of the alternating layers, or strata, of which they are made (Figure 8.22). The magma that creates stratovolcanoes tends to be more viscous, or thick. Viscous lava creates greater pressure which, in turn, tends to create explosive eruptions.

Do composite volcanoes erupt lava?

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 volcanic ash and lava cause layers to form. Over time these layers build up.

What type of volcano is made of lava volcanic ash and cinders?

Composite volcanoes

Composite volcanoes are tall, symetrically shaped, with steep sides, sometimes rising 10,000 feet high. They are built of alternating layers of lava flows, volcanic ash, and cinders.

Which type of volcano contains a lava dome?

stratovolcanoes

Lava domes are one of the principal structural features of many stratovolcanoes worldwide. Lava domes are prone to unusually dangerous explosions since they can contain rhyolitic silica-rich lava.

What are the examples of composite volcano?

Famous examples of composite cones are Mayon Volcano, Philippines, Mount Fuji in Japan, and Mount Rainier, Washington, U.S.A. Some composite volcanoes attain two to three thousand meters in height above their bases. Most composite volcanoes occur in chains and are separated by several tens of kilometers.

Are composite volcanoes explosive or effusive?

Composite volcanoes are tall, steep cones that produce explosive eruptions. Shield volcanoes form very large, gently sloped mounds from effusive eruptions.

What are composite cones?

Composite cones. Composite cones are some of the most easily recognizable and imposing volcanic mountains, with sloping peaks rising several thousand meters above the landscape. Also known as stratocones, composite cones are made up of layers of lava, volcanic ash, and fragmented rocks.

When contrasting lava from a composite volcano to lava from a shield volcano?

When contrasting lava from composite volcanoes to lava from shield volcanoes, composite volcanoes most often produce silica-rich lavas with high viscosities, whereas shield volcanoes produce basaltic lavas with low viscosities.

What does a composite cone volcano look like?

Composite volcanoes. … 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 does a composite volcano look like?

Unlike the shield volcanoes which are flat and broad, composite volcanoes are tall, symmetrically shaped, with steep sides, sometimes rising 10,000 feet high. They are built of alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs.

What are three characteristics of 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.

What are 3 facts about composite volcanoes?

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.

Why do composite volcanoes erupt violently?

Composite cone volcanoes have the most violent eruptions because the magma being erupted is very viscous. This means it doesn’t flow easily.

Was Mount Everest a volcano?

Mount Everest is a volcano located in the Himalayas. It is the highest mountain on Earth, and is also the world’s highest mountain peak. Mount Everest is classified as a stratovolcano, meaning that it is composed of alternating layers of ash and lava.

Is Lahar a lava?

A lahar is a hot or cold mixture of water and rock fragments that flow quickly down the slopes of a volcano. They move up to 40 miles per hour through valleys and stream channels, extending more than 50 miles from the volcano. Lahars can be extremely destructive and are more deadly than lava flows.

How does pahoehoe lava differ from aa lava?

Pahoehoe is lava that in solidified form is characterized by a smooth, billowy, or ropy surface, while aa is lava that has a rough, jagged, spiny, and generally clinkery surface.

Is pahoehoe a pyroclastic material?

The word pyroclastic comes from a Greek word that means “Rock broken by fire”. When volcanoes do produce lava flows they are classified as either Pahoehoe or Aa.

Is pahoehoe lava mafic or felsic?

Mafic lava, which forms much of the oceanic crust, is high in magnesium and iron. Mafic lava is primarily responsible for forming the Hawaiian Islands. Two common forms of mafic lava flow are known by their Hawaiian names: pahoehoe and aa. Pahoehoe lava is billowy lava that is often wrinkled and ropy in appearance.