Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone, 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. How many active volcanoes are there on Earth? There are about 1, potentially active volcanoes worldwide, aside from the continuous belts of volcanoes on the ocean floor at spreading centers like the Mid-Atlantic Ridge.
About of those 1, volcanoes have erupted in historical time. Many of those are located along the Pacific Rim in what is known as the " Ring of Fire. Filter Total Items: Year Published: Yellowstone Volcano Observatory annual report The Yellowstone Volcano Observatory YVO monitors volcanic and hydrothermal activity associated with the Yellowstone magmatic system, conducts research into magmatic processes occurring beneath Yellowstone Caldera, and issues timely warnings and guidance related to potential future geologic hazards.
View Citation. Geological Survey Circular , 44 p. Year Published: update to the U. 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. Ewert, John W. Ewert, J. Geological Survey national volcanic threat assessment: U. Geological Survey Scientific Investigations Report —, 40 p.
Year Published: A field trip guide to the petrology of Quaternary volcanism on the Yellowstone Plateau The Yellowstone Plateau is one of the largest manifestations of silicic volcanism on Earth, and marks the youngest focus of magmatism associated with the Yellowstone Hot Spot. Vazquez, Jorge A. Vazquez, J. Pat; Lowenstern, Jacob B.
Morgan, L. Koch, Richard D. Year Published: Protocols for geologic hazards response by the Yellowstone Volcano Observatory The Yellowstone Plateau hosts an active volcanic system, with subterranean magma molten rock , boiling, pressurized waters, and a variety of active faults with significant earthquake hazards.
Year Published: Preliminary Assessment of Volcanic and Hydrothermal Hazards in Yellowstone National Park and Vicinity Possible future violent events in the active hydrothermal, magmatic, and tectonic system of Yellowstone National Park pose potential hazards to park visitors and infrastructure. Christiansen, Robert L. Patrick; Robinson, Joel E. Year Published: Steam explosions, earthquakes, and volcanic eruptions -- what's in Yellowstone's future? Lowenstern, Jacob B.
Year Published: Tracking changes in Yellowstone's restless volcanic system No abstract available. Stauffer, Peter H. Year Published: 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.
Fournier, Robert O. Filter Total Items: 8. List Grid. This period of volcanism is not related to the present Yellowstone volcano. This ongoing stretching process increased about 17 million years ago and created the modern basin and range topography north—south mountain ranges with long north—south valleys which characterizes much of the West, including the Yellowstone area.
About Subsequent volcanic eruptions can be traced across southern Idaho towards Yellowstone. This mile trail of more than calderas was created as the North American plate moved in a southwestern direction over a shallow body of magma. About 2. This volcanism remains a driving force in Yellowstone today. The Yellowstone supervolcano is one of our planet's restless giants.
Could it erupt in our lifetimes? Discover how geologists are monitoring the pulse of the Yellowstone volcano. Duration: 6 minutes. Siegel, This shallow body of magma is caused by heat convection in the mantle. Plumes of magma rise through the mantle, melting rocks in the crust, and creating magma reservoirs of partially molten, partially solid rock.
Hot spots leave a trail of volcanic activity as tectonic plates drift over them. As the North American Plate drifted westward over the last Heat from the shallowest magma chamber caused an area of the crust above it to expand and rise. Stress on the overlying crust resulted in increased earthquake activity along newly formed faults.
Eventually, these faults reached the magma chamber and magma oozed through the cracks. Escaping magma released pressure within the chamber, which also allowed volcanic gasses to escape and expand explosively in a massive volcanic eruption. The eruption spewed copious volcanic ash and gas into the atmosphere and produced fast, super-hot debris flows pyroclastic flows over the existing landscape.
This eruption 2. The total volcanic material ejected is estimated to have been 6, times the volume of material ejected during the eruption of Mt. Helens, in Washington. A second significant, though smaller, volcanic eruption occurred within the western edge of the first caldera approximately 1. The third and most recent massive volcanic eruption , years ago created the present by mile-wide Yellowstone Caldera. Since then, 80 smaller eruptions have occurred.
Approximately , years ago, one of these created what is now the West Thumb of Yellowstone Lake. During and after these explosive eruptions huge lava flows of viscous rhyolitic lava and less voluminous basalt lava flows partially filled the caldera floor and surrounding terrain. The youngest of these lava flows is the 70, year old Pitchstone rhyolite flow in the southwest corner of Yellowstone National Park.
Since the last of three caldera-forming eruptions, pressure from the shallow magma body has formed two resurgent domes inside the Yellowstone Caldera. Magma may be as little as 3—8 miles beneath Sour Creek Dome and 8—12 miles beneath Mallard Lake Dome, and both domes inflate and subside as the volume of magma or hydrothermal fluids changes beneath them. The entire caldera floor lifts up or subsides, too, but not as much as the two domes. In the past century, the net inflation has tilted the caldera floor toward the south.
Remarkable ground deformation has been documented along the central axis of the caldera between Old Faithful and White Lake in Pelican Valley in historic time.
Surveys of suspected ground deformation began in using vertical-motion surveys of benchmarks in the ground. By the surveys documented unprecedented uplift of the entire caldera in excess of a meter 3 ft. US Geological Survey. When I called up one of the study's co-authors, Jacob Lowenstern of the US Geological Survey, he stressed that the paper was not any sort of prediction of the future.
So I talked to him further about what we actually know about the Yellowstone supervolcano, what its eruptions might look like, and why the odds of disaster are low. Lurking beneath Yellowstone National Park is a reservoir of hot magma five miles deep, fed by a gigantic plume of molten rock welling up from hundreds of miles below. That heat is responsible for many of the park's famous geysers and hot springs.
And as magma rises up into the chamber and cools, the ground above periodically rises and falls. The vast, vast majority of Yellowstone eruptions are small. On rare occasions throughout history, that magma chamber has erupted. The vast, vast majority of those eruptions in Yellowstone have been smaller lava flows — with the last occurring at Pitchstone Plateau some 70, years ago. But the reason why Yellowstone gets so much attention is the remote possibility of catastrophic "super-eruptions.
That's enough to bury Texas five feet deep. These super-eruptions are thousands of times more powerful than even the biggest eruptions we're used to. Helens eruption of The difference is staggering:. Yellowstone has had three of these really massive eruptions in its history — 2. The last of those , at Yellowstone Lava Creek, ejected so much material from below that it left a mile-bymile depression in the ground — what we see today as the Yellowstone Caldera:.
National Park Service. It's worth noting that Yellowstone is hardly the only supervolcano out there — geologists have found evidence of at least 47 super-eruptions in Earth's history.
The most recent occurred in New Zealand's Lake Taupo some 26, years ago. More dramatically, there was the gargantuan Toba eruption 74, years ago, caused by shifting tectonic plates. That triggered a dramatic 6- to year global winter and according to some may have nearly wiped out the nascent human race. On average, the Earth has seen roughly one super-eruption every , years, although that's not an ironclad law.
Let's reiterate that the odds of any sort of Yellowstone eruption, big or small, are very low. But if we're speaking hypothetically…. This would likely be precipitated by a swarm of earthquakes in a specific region of the park as the magma made its way to the surface. A super-eruption is capable of sending ash many thousands of miles. Now, in the unlikely event of a much bigger super-eruption, the warning signs would be much bigger.
It could take weeks or months for those earthquakes to break up the rocks above the magma before an eruption. And what if we did get a super-eruption — an event that was 1, times more powerful than a regular volcanic eruption, ejected at least cubic miles of material, and lasted weeks or months? The lava flows themselves would be contained within a relatively small radius within the park — say, 40 miles or so. In fact, only about one-third of the material would actually make it up into the atmosphere.
The main damage would come from volcanic ash — a combination of splintered rock and glass — that was ejected miles into the air and scattered around the country. In their new paper , Lowenstern and his colleagues looked at both historical ash deposits and advanced modeling to conclude that an eruption would create an umbrella cloud, expanding even in all directions. This was actually a surprising finding. A super-eruption could conceivably bury the northern Rockies in three feet of ash — devastating large swaths of Wyoming, Idaho, Colorado, Montana, and Utah.
Meanwhile, the Midwest would get a few inches of ash, while both coasts would see even smaller amounts. The exact distribution would depend on the time of year and weather patterns:. Mastin et al Any of those scenarios would be terrible news.
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