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 worst-case scenario for a giant Yellowstone eruption is indeed bad and could have global implications, most past eruptions at Yellowstone were not highly explosive. Of the past 50 or so eruptions, almost all were simple lava flows. If they occurred tomorrow or next year, they would have minimal direct effect outside Yellowstone National Park.
As for the worst-case scenario, even previous Yellowstone supereruptions did not cause extinctions, and ash fallout on the other side of the continent was minimal.
Yellowstone is routinely monitored for signs of volcanic activity. These methods include using seismographs to detect earthquakes and using GPS (Global Positioning System) to detect ground motion. The USGS has not detected any signs of activity that suggest an eruption is imminent.
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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...
What would happen if a "supervolcano" eruption occurred again at Yellowstone?
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...
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!
How do scientists know what’s going on beneath the ground at Yellowstone? Is Yellowstone monitored for volcanic activity?
Yellowstone Volcano is monitored for signs of volcanic activity. The Yellowstone Volcano Observatory (YVO) is a partnership between the U.S. Geological Survey (USGS), Yellowstone National Park, the University of Utah, the University of Wyoming, UNAVCO, the Montana Bureau of Mines and Geology, the Idaho Geological Survey, and the Wyoming State Geological Survey. YVO closely monitors volcanic...
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...
Could a large Yellowstone eruption significantly change the climate?
If another catastrophic, caldera-forming Yellowstone eruption were to occur, it would probably alter global weather patterns and have enormous impacts on human activity (especially agricultural production) for many years. At this time, however, scientists do not have the ability to predict specific consequences or durations of possible global impacts from such large eruptions. The 1991 eruption of...
How much volcanic activity has there been at Yellowstone since the most recent giant eruption?
Since the most recent giant (caldera-forming) eruption 631,000 years ago, approximately 80 relatively nonexplosive eruptions have occurred. Of these eruptions, at least 27 were rhyolite lava flows in the caldera, 13 were rhyolite lava flows outside the caldera, and 40 were basalt vents outside the caldera. The most recent volcanic eruption at Yellowstone, a lava flow on the Pitchstone Plateau...
How far in advance could scientists predict an eruption of the Yellowstone volcano?
The science of forecasting a volcanic eruption has significantly advanced over the past 25 years. Most scientists think that the buildup preceding a catastrophic eruption would be detectable for weeks and perhaps months to years. Precursors to volcanic eruptions include strong earthquake swarms and rapid ground deformation and typically take place days to weeks before an actual eruption...
Related Content
- FAQ
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...
What would happen if a "supervolcano" eruption occurred again at Yellowstone?
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...
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!
How do scientists know what’s going on beneath the ground at Yellowstone? Is Yellowstone monitored for volcanic activity?
Yellowstone Volcano is monitored for signs of volcanic activity. The Yellowstone Volcano Observatory (YVO) is a partnership between the U.S. Geological Survey (USGS), Yellowstone National Park, the University of Utah, the University of Wyoming, UNAVCO, the Montana Bureau of Mines and Geology, the Idaho Geological Survey, and the Wyoming State Geological Survey. YVO closely monitors volcanic...
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...
Could a large Yellowstone eruption significantly change the climate?
If another catastrophic, caldera-forming Yellowstone eruption were to occur, it would probably alter global weather patterns and have enormous impacts on human activity (especially agricultural production) for many years. At this time, however, scientists do not have the ability to predict specific consequences or durations of possible global impacts from such large eruptions. The 1991 eruption of...
How much volcanic activity has there been at Yellowstone since the most recent giant eruption?
Since the most recent giant (caldera-forming) eruption 631,000 years ago, approximately 80 relatively nonexplosive eruptions have occurred. Of these eruptions, at least 27 were rhyolite lava flows in the caldera, 13 were rhyolite lava flows outside the caldera, and 40 were basalt vents outside the caldera. The most recent volcanic eruption at Yellowstone, a lava flow on the Pitchstone Plateau...
How far in advance could scientists predict an eruption of the Yellowstone volcano?
The science of forecasting a volcanic eruption has significantly advanced over the past 25 years. Most scientists think that the buildup preceding a catastrophic eruption would be detectable for weeks and perhaps months to years. Precursors to volcanic eruptions include strong earthquake swarms and rapid ground deformation and typically take place days to weeks before an actual eruption...
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