Volcanoes (2024)

FAQs

What is the volcano question answer? ›

A volcano is an opening in the earth's crust through which lava, volcanic ash, and gases escape. Beneath a volcano, liquid magma containing dissolved gases rises through cracks in the Earth's crust. As the magma rises, pressure decreases, allowing the gases to form bubbles.

The Short Answer:

A volcano is an opening on the surface of a planet or moon that allows material warmer than its surroundings to escape from its interior. When this material escapes, it causes an eruption. Lava fountain at Kīlauea Volcano, Hawai`i.

A volcano is a mountain that has lava (hot, liquid rock) coming out from a magma chamber under the ground, or did have in the past. Volcanoes are formed by the movement of tectonic plates. The Earth's crust has 17 major, rigid tectonic plates. These float on a hotter, softer layer in its mantle.

The Ring of Fire is also where an estimated 75% of the planet's volcanoes are located, such as Mount Tambora of Indonesia, which erupted in 1815 and became the largest volcanic eruption in recorded history.

Geologists generally group volcanoes into four main kinds--cinder cones, composite volcanoes, shield volcanoes, and lava domes.

volcano eruptions go through several stages typically beginning with earthquake swarms and gas emissions, then moving to initial steam and ash venting, lava dome buildup, dome collapse, magmatic explosions, more dome growth interspersed with dome failures and finally, ash, lava and pyroclastic eruptions.

Deep within the Earth it is so hot that some rocks slowly melt and become a thick flowing substance called magma. Since it is lighter than the solid rock around it, magma rises and collects in magma chambers. Eventually, some of the magma pushes through vents and fissures to the Earth's surface.

Answer and Explanation: Volcanoes become extinct when they are cut off from their magma flow, thus not having a source a lava to erupt. They initially become dormant and then extinct. Volcanoes are often formed by the movement of tectonic plates grinding or subducting and shifting upwards.

Molten rock below the surface of the Earth that rises in volcanic vents is known as magma, but after it erupts from a volcano it is called lava. Magma is made of molten rock, crystals, and dissolved gas—imagine an unopened bottle of soda with grains of sand inside.

Generally, a volcano is formed when molten rock, ash, and other volcanic materials rise up from the Earth's mantle and accumulate in a magma chamber below the Earth's surface. The depth of this magma chamber can range from a few kilometers to tens of kilometers below the surface.

Why is it called a volcano? ›

The word volcano is derived from the name of Vulcano, a volcanic island in the Aeolian Islands of Italy whose name in turn comes from Vulcan, the god of fire in Roman mythology. The study of volcanoes is called volcanology, sometimes spelled vulcanology.

Expert-Verified Answer. There are lots of countries that do not have volcanoes, some of them include: South Africa, Nigeria, Zimbabwe, Malawi, Djibouti, Somalia, Algeria, Morocco, Tunisia, Liberia, Denmark, Norway, Wales, Finland, Sweden, Ireland...

(As you can see in a graphic in the gallery above.) The United States is home to three active supervolcanoes, the USGS has determined: The famous Yellowstone, Long Valley and the Valles Caldera in New Mexico.

Although Mount Edgecumbe has not erupted in 800 years, recent seismic activity suggests that it might. Small earthquakes have been observed by researchers near the volcano, which raises the possibility that it is about to erupt and seriously endanger the communities nearby.

Volcanoes are formed when the earth's plates move together or apart, causing magma to come up to the earth's surface. When magma reaches the surface, it's called lava. Different mixtures of lava help to create different types of volcanoes, including composite volcanoes, cinder cone volcanoes, and shield volcanoes.

As a volcano erupts, it spills lava that flows downslope. Hot ash and gases are thrown into the air.

A volcanic eruption is the expulsion of gases, rock fragments, and/or molten lava from within the Earth through a vent onto the Earth's surface or into the atmosphere. Illustration of the basic process of magma formation, movement to the surface, and eruption through a volcanic vent. USGS illustration.