Volcanoes

A:

An active volcano is one that has had at least one eruption in the past 10,000 years. An active volcano can be dormant or erupting.

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  • What is the difference between magma and lava?

    Q: What is the difference between magma and lava?

    A: Magma and lava are the same substance in two different forms. Magma is molten rock that is found beneath the earth's crust, while lava is what magma becomes once it reaches the surface and erupts from a volcano or crack in the earth.
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  • What is a mudflow on a volcano called?

    Q: What is a mudflow on a volcano called?

    A: Mudflow on a volcano is called lahar and is typically caused by heavy rains during or after volcanic eruptions. Lahars can also occur when nearby ice or snow melts, carrying ash and rock debris down a volcano's slopes.
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  • What is the Pacific Ring of Fire?

    Q: What is the Pacific Ring of Fire?

    A: The Pacific Ring of Fire is the name for a horseshoe-shaped region of high seismic and volcanic activity surrounding the Pacific Ocean Basin. In addition to volcanoes, the area encompasses major fault zones. It spans 25,000 miles and touches a number of island chains, as well as four continents.
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  • When will Yellowstone erupt?

    Q: When will Yellowstone erupt?

    A: Predicting when the next eruption will occur is difficult; however, the National Science Foundation estimates the next major eruption shouldn't happen for at least another one million years. The next eruption may dump several inches of ash over a large portion of the United States and could change Earth's climate.
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  • What are the main features of a volcano?

    Q: What are the main features of a volcano?

    A: The main features of a volcano include a vent, a summit crater and a magma chamber. The vent is an opening through which volcanic material is erupted. Volcanoes can have more than one vent. The summit crater is the large concave opening that holds the central vent at the top of the volcano. The magma chamber is the large pool-like structure inside the volcano that holds the magma.
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  • Where is Mount Kilimanjaro located?

    Q: Where is Mount Kilimanjaro located?

    A: Mount Kilimanjaro is located in Tanzania. It is a dormant volcano comprising three volcanic cones, and is the highest peak in Africa.
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  • What is a lateral blast?

    Q: What is a lateral blast?

    A: A lateral blast, also known as a lateral eruption, is a volcanic eruption that occurs out of the side of a volcano instead of at its summit. An example of a lateral blast is the 1980 eruption of Mount St. Helens.
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  • What is the oldest volcano in the world?

    Q: What is the oldest volcano in the world?

    A: Mt. Etna is considered the oldest volcano in the world. Its first recorded eruption took place around 1500 B.C.E. Since that date, the volcano is believed to have erupted an additional 190 times.
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  • What are some examples of extinct volcanoes?

    Q: What are some examples of extinct volcanoes?

    A: Some examples of extinct volcanoes include Aconcagua in Argentina, Mount Kenya in Kenya, Mount Ashitaka in Japan and Mount Buninyong in Australia. Extinct volcanoes have been inactive for a long period of time and are considered unlikely to erupt again.
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  • How often does Old Faithful erupt?

    Q: How often does Old Faithful erupt?

    A: Old Faithful erupts at varying intervals from 60 to 110 minutes in length. The Yellowstone National Park staff offers predictions based on past activity; this is so that visitors can plan a visit to the geyser area during an eruption, which lasts between one-and-a-half minutes and five minutes.
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  • How many super volcanoes are there in the world?

    Q: How many super volcanoes are there in the world?

    A: The Earth has approximately 20 known supervolcanoes, according to James Morgan, who write for the BBC News. What constitutes a "supervolcano" is not clearly defined, so the term is avoided in the literature, but it is often used in reference to two distinct phenomena.
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  • What gases are produced by volcanic eruptions?

    Q: What gases are produced by volcanic eruptions?

    A: Volcanic eruptions mainly produce steam (H2 0 ), sulfur dioxide (SO 2 ) and carbon dioxide (CO 2 ). They do release other gases in lesser amounts, such as carbon monoxide (CO), helium (He), hydrogen (H 2 ), hydrogen chloride (HCL), hydrogen fluoride (HF) and hydrogen sulfide (H 2 S).
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  • What is the top of a volcano called?

    Q: What is the top of a volcano called?

    A: The top of a volcano is called the crater. A volcano is shaped like an inverted cone, and the tip of the cone is the crater. The crater is the opening of the vent in a volcano through which the molten magma or the lava is ejected.
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  • What do volcanologists do?

    Q: What do volcanologists do?

    A: Volcanologists study the processes of volcano formation and their eruptive activity. In addition to studying current volcanic activity, they also study the eruptions of volcanoes throughout history.
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  • What are the positive and negative effects of volcanoes?

    Q: What are the positive and negative effects of volcanoes?

    A: The negative effects of volcanoes include the destruction of man-made and natural environments and the death of human, animal and plant life. On the other hand, volcanoes generate geothermal energy and produce nutrients that result in fertile soil.
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  • What country has the most volcanoes?

    Q: What country has the most volcanoes?

    A: Indonesia has the most volcanoes, with 76 volcanoes that have erupted within historical times. The Smithsonian Institution has 141 Indonesian entries in its volcano database; this includes volcanoes which have yet to erupt.
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  • What is an extinct volcano?

    Q: What is an extinct volcano?

    A: An extinct volcano is one that has not erupted in at least 10,000 years and is not expected to erupt in the future, according to Oregon State University. There can be confusion between dormant and extinct volcanoes, but the difference between the two is that a dormant volcano may erupt even if it is in the distant future.
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  • How does a volcano form?

    Q: How does a volcano form?

    A: A volcano forms when a vent in the Earth's crust allows magma to well up from below. The magma fills a void underneath the surface, and when it builds up enough pressure, it bursts through to the surface. As the magma cools, it hardens into rock, and multiple eruptions may build up the mountainous form of a volcano.
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  • How are inselbergs formed?

    Q: How are inselbergs formed?

    A: Inselbergs, or isolated rock hills or mountains, are formed by erosion and long-term weathering. A type of disintegration landform, inselbergs are steep sided and rise abruptly from a gently sloping terrain or level surrounding plain. Their formation may be initiated by a volcanic process that causes a body of relatively erosion-resistant hard rock inside a body of softer rock to rise, which eventually erodes to expose the inner hard-rock portion.
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  • What is an active volcano?

    Q: What is an active volcano?

    A: An active volcano is one that has had at least one eruption in the past 10,000 years. An active volcano can be dormant or erupting.
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  • How was Mount Kilimanjaro formed?

    Q: How was Mount Kilimanjaro formed?

    A: Mount Kilimanjaro is a stratovolcano that formed as the plates below it dropped and porous basalt rock magma erupted through the surface of the ocean. The magma and other debris formed layers with each eruption, eventually rising high enough to bring Mount Kilimanjaro to its height of 19,341 feet.
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