vulkanare some of the most fascinating features on Earth. They were both creators and destroyers: their lava cooled and built new lands, while eruptions of ash and rock buried cities like Pompeii and even blocked the sun. Volcanoes have also inspired artists, writers and scientists for centuries. Read on for some explosive examples of how volcanoes changed the world.
1. There are three main types of volcanoes
The simplest type of volcano,talk cinderIt aptly describes how this type of volcano is formed: as lava erupts from the Earth, it cools and falls back to the surface, and gravel-like ash accumulates around the site of the original eruption. The ember ends as a black, smooth cone. When you look at a map, you can see thousands of cinder cones in western North America and other volcanic regions around the world.
Some of the most majestic mountains on Earth arecomposite volcano- is sometimes calledstratovolcanoThey are usually high, with steep and flat sides, formed by repeated layers of lava flows, volcanic ash, cinders, rocks and volcanic bombs. These mountain volcanoes often result in massive eruptions of thick lava and tephra (small rock fragments) over time. About 60 percent of the world's volcanoes are stratovolcanoes, including Mount St. Helens and Mount Rainier in Washington, Mount Hood in Oregon, Mount Garibaldi in British Columbia and Mount Shasta in California. Some composite volcanoes rise more than 8,000 feet above their surroundings.
shield volcanoBuilt almost entirely from flowing lava flows. Lava ejects or pours out of multiple vents in all directions, spreading across the land. Shield volcanoes are formed slowly from thousands of lava flows that spread over long distances and then cool into thin layers. The crater lake was created when Mount Mazama, a massive shield volcano, collapsed on itself. The snow filled the crater with water, creating a lake. Further eruptions created a small island in the middle of the lake. The Hawaiian Islands consist of a number of shield volcanoes, including Kilauea and Mauna Loa, the largest active volcano in the world.
2. Eruptions are measured by the Volcanic Explosivity Index
The strength of a volcanic eruption is measured on a scale of 0 to 8 based on the amount of lava, ash, and cinders ejected, known as the Volcanic Explosivity Index (VEI). An eruption with a VEI of 0 is essentially quiescent; each subsequent number represents a tenfold increase in ejected material. The eruption of Mount St. Helens in 1980 was VEI 5th for the last timehuge2022 Hunga Tonga Ha'apai Eruption: This explosion destroyed 90% of the South Pacific islands and had a VEI of 6.
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3. ofring of fireis the most active volcanic belt on earth
About 1,350 potentially active volcanoes dot the planet today, about 75 percent of which can be found along the 25,000-mile-long horseshoe-shaped belt bordering the Pacific Ocean. The Pacific Rim, better known asring of fireHome to some of the most volcanically active regions in the world, including Southeast Asia, New Zealand, Japan, Chile, Alaska, and parts of the continental United States.
These volcanoes cluster near subduction zones—unstable areas on Earth where a heavy tectonic plate slides beneath a lighter tectonic plate. These movements cause earthquakes and create magma (lava) where the plates rub against each other. Magma often escapes from lighter plates as volcanoes.
4. The USA has an incredible number of volcanoes
Since the signing of the Declaration of Independence, three volcanoes have erupted in the lower 48 states:Mount St Helensu Washingtonu, Mount Hood, Oregon, iLarsen Peakin California. Mount St. Helens: Eruptions and/or lava dome growth occurred in the late 18th century, 1800-1857, 1980-1986. and 2004-2008.
Lassen Peak: A series of steamy eruptions began on May 30, 1914. It erupted 12 months later on May 21, 1915. Small-scale operations continued until the middle of 1917.
Mount Hood: After being dormant for over 1,000 years, Mount Hood's eruption began in 1781 and lasted for about a decade. In the mid-19th century, local residents reported less bombing activity.
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Thanks to the independence of Alaska and Hawaii in 1959, the United States now leads the world in the number of potentially active volcanoes per country, with 162. This includes the largest active volcano on Earth, Mauna Loa in Hawaii, which is 2.5 miles above sea level and 10, 5 miles above sea level. Miles above the submarine base. Alaska's Novarupta volcano in what is now Katmai National Park and Preserve erupted in the largest eruption of the 20th centuryAndThe century began on June 6, 1912 with the VEI of the 6
5. Volcanoes can change the Earth's climate
The largest volcanic eruptions can throw tons of ash and gases high into the atmosphere, where they block some of the sun's radiation and spread around the world on air currents. These aerosols can actually change the Earth's climate within a few years.
In April 1815, the eruption of Mount Tambora shook present-day Indonesia. The explosion was almost 100 times more powerful than the Mount St Helens eruption in 1980, sending a huge cloud of tiny particles into the atmosphere. As the cloud of particles orbits the Earth, it reflects sunlight, causing the phenomenon we now call ityear without summer.
In June 1991, Mount Pinatubo erupted in the Philippines, spewing ash into the stratosphere and cooling the globe for about two years.
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When the Hunga Tonga-Hunga Ha'apai volcano erupted in January 2022, it caused a global tsunami and a sonic boom that circled the world twice. An underwater eruption in the South Pacific also released massive amounts of water vapor into Earth's stratosphere—enough to fill more than 58,000 Olympic-size swimming pools. The abundance of water vapor could be enough to temporarily affect Earth's global average temperature.
6. A volcano makes the loudest sound ever
When Krakatoa erupted in August 1883, it produced a roar that geologists consider the loudest sound in recorded history. The 310-decibel crash was heard more than 2,000 miles away in Australia, and ranchers believed it was gunfire; 3,000 miles away people thought it was the sound of a cannon from a nearby boat. In addition to the deafening noise, the volcano released 6 cubic miles of material into the atmosphere, causing a tsunami that killed 36,000 people and covered the sea in layers of floating pumice.
The closest we've come to re-imagining Krakatoa is the Hunga Tonga-Hunga Ha'apai eruption off the Polynesian island of Tonga in January 2022. As far north as Alaska, more than 6,000 miles away, Boise State University researchers felt a sonic boom recorded in Idaho on an underground a frequency equivalent to approximately 100 decibels.
Fortunately, the explosion was not so deadly and 3 people died. Still, he did a lot of damage. Tonga was largely cut off from the rest of the world for days as ash covered large areas around it and a tsunami caused extensive damage along its coast. On the island closer to the island, all the houses were destroyed. A few years ago, the volcano created a new island of its own. That, along with parts of two nearby islands, has completely disappeared.
7. Volcanoes erupt, spewing ash on three continents
The active volcano triggered an ash warning earlier this month and sparked tensions in Italy, Mexico and the Democratic Republic of Congo.
On Sunday, May 21, 2023, Mount Etna spewed ash over Catania in eastern Sicily, forcing the airport to temporarily suspend operations. Lava flows were reported in January, and an explosion on May 14 produced ash. Etna's activity has been observed and recorded for over 2,500 years, making it one of the oldest continuously monitored volcanoes.
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Volcanic ash from Popocatepetl caused the temporary closure of Mexico City's Benito Juárez International Airport on Saturday, May 20. There were also reports of flight delays linked to volcanic ash on Monday. People were urged not to travel within a 12.5-mile radius of the volcano and to avoid the crater "due to the risk of falling ballistic fragments," according to Mexico's National Civil Defense Communications and Operations Center. The volcano has been exploding, shaking and spewing steam, gas and ash for weeks, according to reports from the National Center and the National Autonomous University of Mexico.
Eruptions and lava flows also continued at Nyamulagira volcano in the Democratic Republic of Congo. Nyamulagira is the most active volcano in Africa. According to the Smithsonian's Global Volcanic Activity Program, the summit caldera began erupting on March 14, with active eruptions on May 7 and 12. The volcano has been active since April 2018.
According to the Smithsonian's Global Volcanism Program, there were 49 active volcanoes worldwide as of April 14, 2023. According to the program's latest weekly report, 24 volcanoes were in some stage of active eruption last week.
The 730,000-year-old Popocatepetl volcano is said to be the second highest mountain in Mexico; Citlaltépetl is about 500 feet higher. It is the second highest volcano in North America; Mauna Loa in Hawaii is the largest active volcano in the world, rising about 30,000 feet above the sea floor.
Mauna Kea on the island of Hawaii is the highest mountain on Earth if its height is measured from the sea floor; it rises to a height of more than 33,000 feet.
It's worth thinking about...
Each volcano is a separate machine - no, each crater and caldera is currently working on its own special job, cooking its own special dish, which will be served separately in due course. We spew completely different types of lava from vents far apart from each other, neither empathizing with others in any noticeable way nor influencing others to any noticeable degree.
— Clarence Edward DuttonGeological Report on the Utah Plateau(1880)
Stratovolcanoes are more likely to produce explosive eruptions due to gas building up in the viscous magma. Andesite (named after the Andes Mountains), is perhaps the most common rock type of stratovolcanoes, but stratovolcanoes also erupt a wide range of different rocks in different tectonic settings.What are 5 interesting facts about volcanic eruptions? ›
- Major health threats from a volcanic eruption. Volcanoes spew hot, dangerous gases, ash, lava, and rock that are powerfully destructive. People have died from volcanic blasts. ...
- Volcanic ash. Exposure to ash can be harmful. ...
- Gases. Most gases from a volcano quickly blow away.
Stratovolcanoes are more likely to produce explosive eruptions due to gas building up in the viscous magma. Andesite (named after the Andes Mountains), is perhaps the most common rock type of stratovolcanoes, but stratovolcanoes also erupt a wide range of different rocks in different tectonic settings.What are the 7 steps of a volcanic eruption? ›
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.What are the 3 main causes of volcanic eruptions? ›
Although there are several factors triggering a volcanic eruption, three predominate: the buoyancy of the magma, the pressure from the exsolved gases in the magma and the injection of a new batch of magma into an already filled magma chamber.What are 2 known facts about volcanoes? ›
More than 80% of the earth's surface is volcanic in origin. The sea floor and some mountains were formed by countless volcanic eruptions. Gaseous emissions from volcano formed the earth's atmosphere. There are more than 500 active volcanoes in the world.What was the biggest volcanic eruption facts? ›
The world's largest eruption of the 20th century occurred in 1912 at Novarupta on the Alaska Peninsula in what is now Katmai National Park and Preserve. An estimated 15 cubic kilometers of magma was explosively erupted during 60 hours beginning on June 6th.What is the biggest volcano facts? ›
Rising gradually to more than 4 km (2.5 mi) above sea level, Hawaii's Mauna Loa is the largest active volcano on our planet. Its submarine flanks descend to the sea floor an additional 5 km (3 mi), and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km (5 mi).What are the 5 characteristics of a volcano? ›
Answer and Explanation: The five characteristics of a composite volcano involve their lava type, shape, composition, eruption type, and duration between eruptions.What is volcano Class 7? ›
A volcano is a landform, a mountain, where molten rocks erupt through the surface of the planet. The volcano mountain opens downwards to a pool of molten rocks underneath the surface of the earth. Pressure builds up in the earth's crust and this is the reason why eruptions occur.
According to the catalog "Volcanoes of the World" by Smithsonian Institution volcanologists Tom Simkin and Lee Siebert, 9 percent of eruptions end in less than one day, 16 percent within two days, 24 percent within one week, 30 percent within two weeks, 43 percent within a month, 53 percent within two months, 83 ...What are the 2 types of volcanoes that are explosive? ›
There are three basic cone shapes and six eruption types. The three cone shapes are cinder cones, shield cones, and composite cones or stratovolcanoes. The six eruption types are in order from least explosive to the most explosive; Icelandic, Hawaiian, Strombolian, Vulcanian, Pelean, and Plinian.Which volcano is most explosive? ›
There isn't much in Kamchatka, a remote peninsula in northeastern Russia just across the Bering Sea from Alaska, besides an impressive population of brown bears and the most explosive volcano in the world. Kamchatka's Shiveluch volcano has had more than 40 violent eruptions over the last 10,000 years.What do explosive volcanoes have? ›
A volcano's explosiveness depends on the composition of the magma (molten rock) and how readily gas can escape from it. As magma rises and pressure is released, gas bubbles (mainly of water vapor and carbon dioxide) form and expand rapidly, causing explosions.How hot is lava? ›
The temperature of the lava in the tubes is about 1,250 degrees Celsius (2,200 degrees Fahrenheit).What are the 10 parts of erupting volcano? ›
Volcanoes can be of different shapes and sizes, but all contain some basic parts. The essential parts of a typical volcano are: 1) magma chamber, 2) lava, 3) primary vent, 4) throat, 5) conduit, 6) crater, 7) summit, 8) secondary vent, 9) secondary cone, 10) lava flow, and 11) ash cloud.How does a volcano erupt step by step? ›
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.What makes a volcano erupt? ›
The melted rock, or magma, is lighter than the surrounding rock and rises up. This magma collects in magma chambers, but it is still miles below the surface. When enough magma builds up in the magma chamber, it forces its way up to the surface and erupts, often causing volcanic eruptions.How often do volcanoes erupt? ›
Since there are on average between 50 and 60 volcanoes that erupt each year somewhere on Earth (about 1 every week), some of Earth's volcanoes may actually erupt within a few days or hours of each other.How old are volcanoes? ›
Volcanoes and earthquakes could have started as far back as 3.8 billion years ago.
How Long Does it Take a Volcano to Grow? Volcanoes are created over approximately 10,000-500,000 years by thousands of eruptions -- each lava flow covering the one before it. In the case of oceanic island volcanoes, lava erupts first from fissures, or cracks, on the deep ocean floor.How many people have died from volcanoes? ›
|Human death toll||Volcano||Year|
|23,000||Nevado del Ruiz||1985|
|20,000~ (estimated)||Santorini||c. 1600 BC|
- The first recorded volcanic eruption: Vesuvius (79 AD) ...
- The longest volcanic eruption: Yasur (1774-present) ...
- The deadliest volcanic eruption: Tambora (1815) ...
- The loudest volcanic eruption: Krakatoa (1883) ...
- The most expensive volcanic eruption: Nevado del Ruiz (1985)
Paricutin is the world's youngest volcano. The story starts in Mexico in 1943, near the village of Paricutin, in the state of Michoacán, located about 320 kilometers west of Mexico City. In particular, it starts with a single farmer by the name of Dionisio Pulido.What is a famous volcano eruption? ›
In 1815, Mount Tambora erupted on Sumbawa, an island of modern-day Indonesia. Historians regard it as the volcano eruption with the deadliest known direct impact: roughly 100,000 people died in the immediate aftermath.What is the 3 biggest volcano in the world? ›
|Volcano, location||Height in meters|
|Mauna Loa (Hawaii, United States)||9,170|
|Mount Kilimanjaro (Tanzania)*||5,895|
|Popocatépetl Volcano (Mexico)||5,426|
|Mount Fuji (Tokyo, Japan)||3,776|
Lava is hot, liquefied rock that flows from a volcano or other opening in the surface of Earth. When the liquid rock is still underground it is known as magma. Igneous rock is formed when lava cools and hardens.What are the top 3 biggest volcanoes? ›
The top 3 biggest volcanoes are Tamu Massif (Pacific Ocean), Mauna Loa (Hawaii), and Ojos del Salado (Chile).What are 4 features of a volcano? ›
The main features of a volcano include the magma chamber, vents, craters and slopes.What are three types of volcanoes? ›
The most well-known types of volcanoes are cinder cones, composite volcanoes (stratovolcanoes), and shield volcanoes.
They are: (1) initial - deep submarine stage, (2) submarine - shield building stage, (3) sea level - shield building stage, (4) subaerial - shield building stage, (5) capping stage, (6) erosional stage - reef growth, (7) renewed volcanism stage, and (8) atoll stage.How are volcanoes made? ›
Magma rises from the hot spots and erupts as lava through cracks in the Earth's surface forming volcanoes. As a plate moves slowly across a hot spot, a chain of volcanoes or volcanic islands can form. The islands of Hawaii and Samoa were formed in this way.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.Can a dead volcano erupt again? ›
There are many volcanic systems, however, that can go quiet for thousands of years and then reawaken. Mount St. Helens, for example, was dormant from about 11,000 years ago to about 4,000 years ago, after which time it has erupted very frequently.Can a volcano erupt 2 times? ›
Some small volcanoes only erupt once in their lives, while other volcanoes erupt multiple times. Kilaeua volcano in Hawaii, which has been erupting continuously since 1983, is the world's most active volcano.How fast does lava flow? ›
The leading edges of basalt flows can travel as fast as 10 km/h (6 mph) on steep slopes but they typically advance less than 1 km/h (0.27 m/s or about 1 ft/s) on gentle slopes.Which volcano is the least explosive? ›
Basalt plateau refers to an extensive, thick, smooth flow or succession of flows of high-temperature, fluid basalt erupted from fissures, flooding topographic lows, and accumulated to form a plateau. It is the least explosive type of volcano.What is a GREY volcano? ›
Explosively eruptive volcanoes frequently produce grey eruption clouds that rise high into the sky. The lava of these volcanoes is richer in gas, more viscous and cooler than that of "red volcanism". They have great destructive potential.What volcano is violent and explosive? ›
Icelandic eruptions are mainly vent eruptions whereas Hawaiian eruptions are often associated with large volcanoes. As seen in Figure 5.28, explosive volcanoes, in order of increasing VEI and size, create Strombolian, Vulcanian, Peléan, Plinian, ultra-Plinian, and supervolcano eruptions.What are the six types of eruptions? ›
Public domain.) The small-scale explosive activity of lava fountains shreds and blasts molten rock into the air, forming a variety of lava fragments that solidify as tephra and fall back to the ground. Most fragments land within a few hundred meters from the vent, typically forming a spatter cone or rampart.What are the 4 types of volcanic eruptions? ›
There are four types of eruptions with properties determined mostly by the silica content of magma, and the amount of gas it contains. In order of increasing explosiveness, these are Hawai'ian, Strombolian, Vulcanian, and Plinian eruptions.Are explosive eruptions fast? ›
Explosive eruptions can expel as much as 1,000 kg (2,200 lb) per second of rocks, dust, gas and pyroclastic material, averaged over the duration of eruption, that travels at several hundred meters per second as high as 20 km (12 mi) into the atmosphere.What was the worst volcanic eruption facts? ›
Since the late 1700s, volcanoes have caused more than 250,000 deaths. Most of these occurred during four disastrous eruptions. The largest of the four occurred on April 10–11, 1815, at Mount Tambora on Sumbawa Island, now a part of Indonesia.How long does a volcano eruption last? ›
According to the catalog "Volcanoes of the World" by Smithsonian Institution volcanologists Tom Simkin and Lee Siebert, 9 percent of eruptions end in less than one day, 16 percent within two days, 24 percent within one week, 30 percent within two weeks, 43 percent within a month, 53 percent within two months, 83 ...How fast are volcanoes? ›
Pyroclastic density currents are hot, fast moving "clouds" of gas, ash, and rock debris known as tephra. They can reach temperatures up to 1,000 degrees Celsius and speeds of 700 kilometers per hour and are much denser than the surrounding air.What are the most explosive volcanoes called? ›
Caldera Volcanoes: Calderas Volcanoes are known as the most explosive volcanoes on Earth. When they erupt, they incline to drop on themselves rather than constructing any structure.What is the biggest volcano explosion? ›
Hundreds of articles have been written about the largest volcanic eruption in recorded history, at Indonesia's Mt. Tambora just over 200 years ago...What are the 3 biggest volcanoes in the world? ›
The top 3 biggest volcanoes are Tamu Massif (Pacific Ocean), Mauna Loa (Hawaii), and Ojos del Salado (Chile).Which volcano killed most people? ›
Pelean and Plinian eruptions are the most dangerous and explosive of the eruption types. Pelean eruptions are named for the catastophic eruption on the island of Martinique in the Carribean Sea in 1902.What was the most violent eruption? ›
The most violent eruption registered in history was that in the La Garita Caldera in the United States. It occurred 2.1 million years ago and formed a 35 x 75 km crater, drastically changing the climate on Earth. Fortunately, these eruptions are rare: they occur every 50,000 or 100,000 years.What volcano had the worst day in history? ›
In 1815, Mount Tambora on the island of Sumbawa (present-day Indonesia) erupted causing the most powerful volcanic eruption ever recorded in human history, spewing tons of sulphur dioxide into the atmosphere causing global temperatures to fall.How many volcanoes are erupting right now? ›
Overall, 49 volcanoes were in continuing eruption status as of 14 April 2023. An eruption marked as "continuing" does not always mean persistent daily activity, but indicates at least intermittent eruptive events without a break of 3 months or more.