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If another large, caldera-forming eruption were to occur at Yellowstone, its effects would be worldwide. Such a giant eruption would have regional effects such as falling ash and short-term (years to decades) changes to global climate. Those parts of the surrounding states of Montana, Idaho, and Wyoming that are closest to Yellowstone would be affected by pyroclastic flows, while other places in the United States would be impacted byfalling ash (the amount of ash would decrease with distance from the eruption site). Such eruptions usually formcalderas, broad volcanic depressions created as the ground surface collapses as a result of withdrawal of partially molten rock (magma) below. Fortunately, the chances of this sort of eruption at Yellowstone are exceedingly small in the next few thousands of years.
Learn more:
Related Content
- FAQ
- Multimedia
- Publications
- News
How big is the magma chamber under Yellowstone?
Yellowstone is underlain by two magma bodies. The shallower one is composed of rhyolite (a high-silica rock type) and stretches from 5 km to about 17 km (3 to 10 mi) beneath the surface and is about 90 km (55 mi) long and about 40 km (25 mi) wide. The chamber is mostly solid, with only about 5-15% melt. The deeper reservoir is composed of basalt (a low-silica rock type) and extends from 20 to 50...
Yellowstone is underlain by two magma bodies. The shallower one is composed of rhyolite (a high-silica rock type) and stretches from 5 km to about 17 km (3 to 10 mi) beneath the surface and is about 90 km (55 mi) long and about 40 km (25 mi) wide. The chamber is mostly solid, with only about 5-15% melt. The deeper reservoir is composed of basalt (a low-silica rock type) and extends from 20 to 50...
What is the difference between "magma" and "lava"?
Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth's surface.
Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth's surface.
When was the last time Yellowstone erupted?
The most recent volcanic activity at Yellowstone consisted of rhyolitic lava flows that erupted approximately 70,000 years ago. The largest of these flows formed the Pitchstone Plateau in southwestern Yellowstone National Park. Learn more: Yellowstone Eruption History The evolution of the Yellowstone Plateau Volcani Field: Past, present, and future!
The most recent volcanic activity at Yellowstone consisted of rhyolitic lava flows that erupted approximately 70,000 years ago. The largest of these flows formed the Pitchstone Plateau in southwestern Yellowstone National Park. Learn more: Yellowstone Eruption History The evolution of the Yellowstone Plateau Volcani Field: Past, present, and future!
Why are there so many earthquakes at Yellowstone?
Almost all earthquakes at Yellowstone are brittle-failure events caused when rocks break due to crustal stresses. Though we've been looking at Yellowstone for years, no one has yet identified "long-period (LP) events" commonly attributed to magma movement. If LP events are observed, that will NOT mean Yellowstone is getting ready to erupt. LP earthquakes commonly occur at other volcanoes in the...
Almost all earthquakes at Yellowstone are brittle-failure events caused when rocks break due to crustal stresses. Though we've been looking at Yellowstone for years, no one has yet identified "long-period (LP) events" commonly attributed to magma movement. If LP events are observed, that will NOT mean Yellowstone is getting ready to erupt. LP earthquakes commonly occur at other volcanoes in the...
Can we drill into Yellowstone to stop it from erupting?
In some cases, limited scientific drilling for research can help us understand magmatic and hydrothermal (hot water) systems; however, drilling to mitigate a volcanic threat is a much different subject with unknown consequences, high costs, and severe environmental impacts. In addition to the enormous expense and technological difficulties in drilling through hot, mushy rock, drilling is unlikely...
In some cases, limited scientific drilling for research can help us understand magmatic and hydrothermal (hot water) systems; however, drilling to mitigate a volcanic threat is a much different subject with unknown consequences, high costs, and severe environmental impacts. In addition to the enormous expense and technological difficulties in drilling through hot, mushy rock, drilling is unlikely...
What type of eruption will Yellowstone have if it erupts again?
The most likely explosive event to occur at Yellowstone is actually a hydrothermal explosion (a rock hurling geyser eruption) or a lava flow. Hydrothermal explosions are very small; they occur in Yellowstone National Park every few years and form a crater a few meters across. Every few thousand years, a hydrothermal explosion will form a crater as much as a few hundred meters across. Though the...
The most likely explosive event to occur at Yellowstone is actually a hydrothermal explosion (a rock hurling geyser eruption) or a lava flow. Hydrothermal explosions are very small; they occur in Yellowstone National Park every few years and form a crater a few meters across. Every few thousand years, a hydrothermal explosion will form a crater as much as a few hundred meters across. Though the...
How far would ash travel if Yellowstone had a large explosive eruption?
Knowledge about past eruptions of Yellowstone combined with mathematical models of volcanic ash dispersion help scientists determine where and how much ashfall will occur in possible future eruptions. During the three caldera-forming eruptions that occurred between 2.1 million and 640,000 years ago, tiny particles of volcanic ash covered much of the western half of North America. That ash was...
How far would ash travel if Yellowstone had a large explosive eruption?
Knowledge about past eruptions of Yellowstone combined with mathematical models of volcanic ash dispersion help scientists determine where and how much ashfall will occur in possible future eruptions. During the three caldera-forming eruptions that occurred between 2.1 million and 640,000 years ago, tiny particles of volcanic ash covered much of the western half of North America. That ash was...
What is a supervolcano? What is a supereruption?
The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that...
The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that...
What are some examples of supervolcanoes?
Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other 'supervolcanoes' would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g. Aniakchak, Emmons, Fisher), and other areas...
Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other 'supervolcanoes' would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g. Aniakchak, Emmons, Fisher), and other areas...
Inside USGS, No. 6, Ken Pierce, Heavy Breathing of Yellowstone Caldera
Forecasting Ashfall Impacts from a Yellowstone Supereruption
The Yellowstone Volcano: Past, Present and Future
Caldera Demonstration Model
Yes! Yellowstone is a Volcano (Part 1 of 3)
Yellowstone Volcano Observatory (Part 2 of 3)
Yellowstone Eruptions (Part 3 of 3)
Volcano and earthquake monitoring plan for the Yellowstone Caldera system, 2022–2032
Executive SummaryThe Yellowstone Volcano Observatory (YVO) is a consortium of nine Federal, State, and academic agencies that: (1) provides timely monitoring and hazards assessment of volcanic, hydrothermal, and earthquake activity in and around Yellowstone National Park, and (2) conducts research to develop new approaches to volcano monitoring and better understand volcanic activity in the Yellow
Living with volcano hazards
Volcanic eruptions are among Earth’s most dramatic and powerful agents of change. Ash, mudflows, and lava flows can devastate communities near volcanoes and cause havoc in areas far downwind, downstream, and downslope. Even when a volcano is quiet, steep volcanic slopes can collapse to become landslides, and large rocks can be hurled by powerful steam blasts. Hazardous volcanic conditions might la
Authors
Wendy K. Stovall, Carolyn L. Driedger, Elizabeth G. Westby, Lisa M. Faust
2018 update to the U.S. Geological Survey national volcanic threat assessment
When erupting, all volcanoes pose a degree of risk to people and infrastructure, however, the risks are not equivalent from one volcano to another because of differences in eruptive style and geographic location. Assessing the relative threats posed by U.S. volcanoes identifies which volcanoes warrant the greatest risk-mitigation efforts by the U.S. Geological Survey and its partners. This update
Authors
John W. Ewert, Angela K. Diefenbach, David W. Ramsey
By
Volcano Hazards Program, Volcano Science Center, Agrigan, Ahyi Seamount, Alamagan, Anatahan, Asuncion, Belknap, Black Butte Crater Lava Field, Black Rock Desert Volcanic Field, Blue Lake Crater, Carrizozo Lava Flow, Cascade Range Weekly Update, Cinnamon Butte, Clear Lake Volcanic Field, Coso Volcanic Field, Crater Lake, Craters of the Moon Volcanic Field, Daikoku Seamount , Davis Lake Volcanic Field, Devils Garden Lava Field, Diamond Craters Volcanic Field, Dotsero Volcanic Center, East Diamante, Esmeralda Bank, Farallon de Pajaros, f*ckujin Seamount , Glacier Peak, Guguan, Haleakalā, Hell's Half Acre Lava Field, Hualālai, Indian Heaven Volcanic Field, Jordan Craters Volcanic Field, Kama‘ehuakanaloa, Kasuga 2, Kīlauea, Lassen Volcanic Center, Long Valley Caldera, Mammoth Mountain, Markagunt Plateau Volcanic Field, Maug Islands, Mauna Kea, Mauna Loa, Medicine Lake, Mono Lake Volcanic Field, Mono-Inyo Craters, Mount Adams, Mount Bachelor, Mount Baker, Mount Hood, Mount Jefferson, Mount Rainier, Mount Shasta, Mount St. Helens, Newberry, Ofu-Olosega, Pagan, Red Hill-Quemado Volcanic Field, Ruby, Salton Buttes, San Francisco Volcanic Field, Sand Mountain Volcanic Field, Sarigan, Soda Lakes, South Sarigan Seamount, Supply Reef, Ta'u Island, Three Sisters, Tutuila Island, Ubehebe Craters, Uinkaret Volcanic Field, Valles Caldera, Wapi Lava Field, Weekly Update, West Crater Volcanic Field, Yellowstone, Zealandia Bank, Zuni-Bandera Volcanic Field
U.S. Geological Survey Volcano Hazards Program—Assess, forecast, prepare, engage
At least 170 volcanoes in 12 Statesand 2 territories have erupted inthe past 12,000 years and havethe potential to erupt again.Consequences of eruptions fromU.S. volcanoes can extend farbeyond the volcano’s immediatearea. Many aspects of our daily lifeare vulnerable to volcano hazards,including air travel, regionalpower generation and transmissioninfrastructure, interstatetransportatio
Authors
Wendy K. Stovall, Aleeza M. Wilkins, Charlie Mandeville, Carolyn L. Driedger
Steam explosions, earthquakes, and volcanic eruptions -- what's in Yellowstone's future?
Yellowstone, one of the world’s largest active volcanic systems, has produced several giant volcanic eruptions in the past few million years, as well as many smaller eruptions and steam explosions. Although no eruptions of lava or volcanic ash have occurred for many thousands of years, future eruptions are likely. In the next few hundred years, hazards will most probably be limited to ongoing geys
Authors
Jacob B. Lowenstern, Robert L. Christiansen, Robert B. Smith, Lisa A. Morgan, Henry Heasler
Tracking changes in Yellowstone's restless volcanic system
No abstract available.
Authors
Peter H. Stauffer
The Quaternary and Pliocene Yellowstone Plateau volcanic field of Wyoming, Idaho, and Montana
This region of Yellowstone National Park has been the active focus of one of the Earth's largest magmatic systems for more than 2 million years. The resulting volcanism has been characterized by the eruption of voluminous rhyolites and subordinate basalts but virtually no lavas of intermediate composition. The magmatic system at depth remains active and drives the massive hydrothermal circulation
Authors
Robert L. Christiansen
Volcanic ash fall - a "hard rain" of abrasive particles
No abstract available.
Authors
Christopher A. Kenedi, Steven R. Brantley, James W. Hendley, Peter H. Stauffer
The National Volcano Early Warning System (NVEWS) will help USGS better monitor nation’s most dangerous volcanoes
In September 2004, USGS scientists detected sudden, but unmistakable, signs that Mount St. Helens was waking up. Volcano monitorshad picked up the...
Related Content
- FAQ
How big is the magma chamber under Yellowstone?
Yellowstone is underlain by two magma bodies. The shallower one is composed of rhyolite (a high-silica rock type) and stretches from 5 km to about 17 km (3 to 10 mi) beneath the surface and is about 90 km (55 mi) long and about 40 km (25 mi) wide. The chamber is mostly solid, with only about 5-15% melt. The deeper reservoir is composed of basalt (a low-silica rock type) and extends from 20 to 50...
Yellowstone is underlain by two magma bodies. The shallower one is composed of rhyolite (a high-silica rock type) and stretches from 5 km to about 17 km (3 to 10 mi) beneath the surface and is about 90 km (55 mi) long and about 40 km (25 mi) wide. The chamber is mostly solid, with only about 5-15% melt. The deeper reservoir is composed of basalt (a low-silica rock type) and extends from 20 to 50...
What is the difference between "magma" and "lava"?
Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth's surface.
Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth's surface.
When was the last time Yellowstone erupted?
The most recent volcanic activity at Yellowstone consisted of rhyolitic lava flows that erupted approximately 70,000 years ago. The largest of these flows formed the Pitchstone Plateau in southwestern Yellowstone National Park. Learn more: Yellowstone Eruption History The evolution of the Yellowstone Plateau Volcani Field: Past, present, and future!
The most recent volcanic activity at Yellowstone consisted of rhyolitic lava flows that erupted approximately 70,000 years ago. The largest of these flows formed the Pitchstone Plateau in southwestern Yellowstone National Park. Learn more: Yellowstone Eruption History The evolution of the Yellowstone Plateau Volcani Field: Past, present, and future!
Why are there so many earthquakes at Yellowstone?
Almost all earthquakes at Yellowstone are brittle-failure events caused when rocks break due to crustal stresses. Though we've been looking at Yellowstone for years, no one has yet identified "long-period (LP) events" commonly attributed to magma movement. If LP events are observed, that will NOT mean Yellowstone is getting ready to erupt. LP earthquakes commonly occur at other volcanoes in the...
Almost all earthquakes at Yellowstone are brittle-failure events caused when rocks break due to crustal stresses. Though we've been looking at Yellowstone for years, no one has yet identified "long-period (LP) events" commonly attributed to magma movement. If LP events are observed, that will NOT mean Yellowstone is getting ready to erupt. LP earthquakes commonly occur at other volcanoes in the...
Can we drill into Yellowstone to stop it from erupting?
In some cases, limited scientific drilling for research can help us understand magmatic and hydrothermal (hot water) systems; however, drilling to mitigate a volcanic threat is a much different subject with unknown consequences, high costs, and severe environmental impacts. In addition to the enormous expense and technological difficulties in drilling through hot, mushy rock, drilling is unlikely...
In some cases, limited scientific drilling for research can help us understand magmatic and hydrothermal (hot water) systems; however, drilling to mitigate a volcanic threat is a much different subject with unknown consequences, high costs, and severe environmental impacts. In addition to the enormous expense and technological difficulties in drilling through hot, mushy rock, drilling is unlikely...
What type of eruption will Yellowstone have if it erupts again?
The most likely explosive event to occur at Yellowstone is actually a hydrothermal explosion (a rock hurling geyser eruption) or a lava flow. Hydrothermal explosions are very small; they occur in Yellowstone National Park every few years and form a crater a few meters across. Every few thousand years, a hydrothermal explosion will form a crater as much as a few hundred meters across. Though the...
The most likely explosive event to occur at Yellowstone is actually a hydrothermal explosion (a rock hurling geyser eruption) or a lava flow. Hydrothermal explosions are very small; they occur in Yellowstone National Park every few years and form a crater a few meters across. Every few thousand years, a hydrothermal explosion will form a crater as much as a few hundred meters across. Though the...
How far would ash travel if Yellowstone had a large explosive eruption?
Knowledge about past eruptions of Yellowstone combined with mathematical models of volcanic ash dispersion help scientists determine where and how much ashfall will occur in possible future eruptions. During the three caldera-forming eruptions that occurred between 2.1 million and 640,000 years ago, tiny particles of volcanic ash covered much of the western half of North America. That ash was...
Knowledge about past eruptions of Yellowstone combined with mathematical models of volcanic ash dispersion help scientists determine where and how much ashfall will occur in possible future eruptions. During the three caldera-forming eruptions that occurred between 2.1 million and 640,000 years ago, tiny particles of volcanic ash covered much of the western half of North America. That ash was...
What is a supervolcano? What is a supereruption?
The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that...
The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that...
What are some examples of supervolcanoes?
Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other 'supervolcanoes' would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g. Aniakchak, Emmons, Fisher), and other areas...
Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other 'supervolcanoes' would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g. Aniakchak, Emmons, Fisher), and other areas...
- Multimedia
Inside USGS, No. 6, Ken Pierce, Heavy Breathing of Yellowstone Caldera
Forecasting Ashfall Impacts from a Yellowstone Supereruption
The Yellowstone Volcano: Past, Present and Future
Caldera Demonstration Model
Yes! Yellowstone is a Volcano (Part 1 of 3)
Yellowstone Volcano Observatory (Part 2 of 3)
Yellowstone Eruptions (Part 3 of 3)
- Publications
Volcano and earthquake monitoring plan for the Yellowstone Caldera system, 2022–2032
Executive SummaryThe Yellowstone Volcano Observatory (YVO) is a consortium of nine Federal, State, and academic agencies that: (1) provides timely monitoring and hazards assessment of volcanic, hydrothermal, and earthquake activity in and around Yellowstone National Park, and (2) conducts research to develop new approaches to volcano monitoring and better understand volcanic activity in the Yellow
Living with volcano hazards
Volcanic eruptions are among Earth’s most dramatic and powerful agents of change. Ash, mudflows, and lava flows can devastate communities near volcanoes and cause havoc in areas far downwind, downstream, and downslope. Even when a volcano is quiet, steep volcanic slopes can collapse to become landslides, and large rocks can be hurled by powerful steam blasts. Hazardous volcanic conditions might la
Authors
Wendy K. Stovall, Carolyn L. Driedger, Elizabeth G. Westby, Lisa M. Faust
2018 update to the U.S. Geological Survey national volcanic threat assessment
When erupting, all volcanoes pose a degree of risk to people and infrastructure, however, the risks are not equivalent from one volcano to another because of differences in eruptive style and geographic location. Assessing the relative threats posed by U.S. volcanoes identifies which volcanoes warrant the greatest risk-mitigation efforts by the U.S. Geological Survey and its partners. This update
Authors
John W. Ewert, Angela K. Diefenbach, David W. Ramsey
By
Volcano Hazards Program, Volcano Science Center, Agrigan, Ahyi Seamount, Alamagan, Anatahan, Asuncion, Belknap, Black Butte Crater Lava Field, Black Rock Desert Volcanic Field, Blue Lake Crater, Carrizozo Lava Flow, Cascade Range Weekly Update, Cinnamon Butte, Clear Lake Volcanic Field, Coso Volcanic Field, Crater Lake, Craters of the Moon Volcanic Field, Daikoku Seamount , Davis Lake Volcanic Field, Devils Garden Lava Field, Diamond Craters Volcanic Field, Dotsero Volcanic Center, East Diamante, Esmeralda Bank, Farallon de Pajaros, f*ckujin Seamount , Glacier Peak, Guguan, Haleakalā, Hell's Half Acre Lava Field, Hualālai, Indian Heaven Volcanic Field, Jordan Craters Volcanic Field, Kama‘ehuakanaloa, Kasuga 2, Kīlauea, Lassen Volcanic Center, Long Valley Caldera, Mammoth Mountain, Markagunt Plateau Volcanic Field, Maug Islands, Mauna Kea, Mauna Loa, Medicine Lake, Mono Lake Volcanic Field, Mono-Inyo Craters, Mount Adams, Mount Bachelor, Mount Baker, Mount Hood, Mount Jefferson, Mount Rainier, Mount Shasta, Mount St. Helens, Newberry, Ofu-Olosega, Pagan, Red Hill-Quemado Volcanic Field, Ruby, Salton Buttes, San Francisco Volcanic Field, Sand Mountain Volcanic Field, Sarigan, Soda Lakes, South Sarigan Seamount, Supply Reef, Ta'u Island, Three Sisters, Tutuila Island, Ubehebe Craters, Uinkaret Volcanic Field, Valles Caldera, Wapi Lava Field, Weekly Update, West Crater Volcanic Field, Yellowstone, Zealandia Bank, Zuni-Bandera Volcanic Field
U.S. Geological Survey Volcano Hazards Program—Assess, forecast, prepare, engage
At least 170 volcanoes in 12 Statesand 2 territories have erupted inthe past 12,000 years and havethe potential to erupt again.Consequences of eruptions fromU.S. volcanoes can extend farbeyond the volcano’s immediatearea. Many aspects of our daily lifeare vulnerable to volcano hazards,including air travel, regionalpower generation and transmissioninfrastructure, interstatetransportatio
Authors
Wendy K. Stovall, Aleeza M. Wilkins, Charlie Mandeville, Carolyn L. Driedger
Steam explosions, earthquakes, and volcanic eruptions -- what's in Yellowstone's future?
Yellowstone, one of the world’s largest active volcanic systems, has produced several giant volcanic eruptions in the past few million years, as well as many smaller eruptions and steam explosions. Although no eruptions of lava or volcanic ash have occurred for many thousands of years, future eruptions are likely. In the next few hundred years, hazards will most probably be limited to ongoing geys
Authors
Jacob B. Lowenstern, Robert L. Christiansen, Robert B. Smith, Lisa A. Morgan, Henry Heasler
Tracking changes in Yellowstone's restless volcanic system
No abstract available.
Authors
Peter H. Stauffer
The Quaternary and Pliocene Yellowstone Plateau volcanic field of Wyoming, Idaho, and Montana
This region of Yellowstone National Park has been the active focus of one of the Earth's largest magmatic systems for more than 2 million years. The resulting volcanism has been characterized by the eruption of voluminous rhyolites and subordinate basalts but virtually no lavas of intermediate composition. The magmatic system at depth remains active and drives the massive hydrothermal circulation
Authors
Robert L. Christiansen
Volcanic ash fall - a "hard rain" of abrasive particles
No abstract available.
Authors
Christopher A. Kenedi, Steven R. Brantley, James W. Hendley, Peter H. Stauffer
- News
The National Volcano Early Warning System (NVEWS) will help USGS better monitor nation’s most dangerous volcanoes
In September 2004, USGS scientists detected sudden, but unmistakable, signs that Mount St. Helens was waking up. Volcano monitorshad picked up the...
