A new simulation illustrates the explosiveness of the volcano that lurks beneath Yellowstone National Park in Wyoming.
Road Melting in Yellowstone!
YELLOWSTONE ANIMALS FLEEING PARK. SUPERVOLCANO ERUPTION IMMINENT? | PoliticalEars.com - April 2, 2014
Yellowstone Earthquake: Volcanic Eruption Not Expected After Strongest Tremor in 34 Years | Weather.com - March 31, 2014
Yellowstone National Park was shaken by its largest earthquake in 34 years Sunday, but scientists say there is no concern that the quake will lead to an eruption of the Yellowstone Caldera, a supervolcano located in the park.
A sleeping super volcano shook up Yellowstone National Park early this morning at 6:34 a.m. and registered a 4.8 magnitude earthquake, but geologists say the shake up should be of no concern. The tremor rattled the border between Wyoming and Nevada, nearly in the center of the historic park, near the Norris Geyser Basin. The last earthquake of this magnitude occurred thirty years ago in 1985.
Scientists report that if the super volcano erupted it would decimate the United States with ash and affect the entire earth. Many people are concerned about seismic activity, suspecting the super volcano is due for an eruption. Peter Cervelli of The US Geological Survey says this particular rattle is nothing to worry about and the caldera is not about to erupt. The earthquake is interesting though because of the amount of time between the two strongest tremors. The data scientists will collect from the event will add to the insight of volcanoes and tectonics, he added. But this particular super volcano is still sleeping and should bring no concern.
The supervolcano that lies beneath Yellowstone National Park in the US is far larger than was previously thought, scientists report.
A study shows that the magma chamber is about 2.5 times bigger than earlier estimates suggested.
A team found the cavern stretches for more than 90km (55 miles) and contains 200-600 cubic km of molten rock.
The findings are being presented at the American Geophysical Union Fall Meeting in San Francisco.
Prof Bob Smith, from the University of Utah, said: “We’ve been working there for a long time, and we’ve always thought it would be bigger... but this finding is astounding."
If the Yellowstone supervolcano were to blow today, the consequences would be catastrophic.
The last major eruption, which occurred 640,000 years ago, sent ash across the whole of North America, affecting the planet’s climate.
Now researchers believe they have a better idea of what lies beneath the ground.
The team used a network of seismometers that were situated around the park to map the magma chamber.
Dr Jamie Farrell, from the University of Utah, explained: “We record earthquakes in and around Yellowstone, and we measure the seismic waves as they travel through the ground.
“The waves travel slower through hot and partially molten material… with this, we can measure what’s beneath.”
The team found that the magma chamber was colossal. Reaching depths of between 2km and 15km (1 to 9 miles), the cavern was about 90km (55 miles) long and 30km (20 miles) wide.
It pushed further into the north east of the park than other studies had previously shown, holding a mixture of solid and molten rock.
“To our knowledge there has been nothing mapped of that size before,” added Dr Farrell.
The researchers are using the findings to better assess the threat that the volatile giant poses.
“Yes, it is a much larger system… but I don’t think it makes the Yellowstone hazard greater,” explained Prof Bob Smith.
“But what it does tell us is more about the area to the north east of the caldera.”
He added that researchers were unsure when the supervolcano would blow again.
Some believe a massive eruption is overdue, estimating that Yellowstone’s volcano goes off every 700,000 years or so.
But Prof Smith said more data was needed, because there had only been three major eruptions so far. These happened 2.1 million years ago, 1.3 million years ago and 640,000 years ago.
“You can only use the time between eruptions (to work out the frequency), so in a sense you only have two numbers to get to that 700,000 year figure,” he explained.
“How many people would buy something on the stock market on two days of stock data.”
In another study presented at the AGU Fall Meeting, researchers have been looking at other, more ancient volcanic eruptions that happened along the same stretch of continental plate that Yellowstone’s supervolcano sits on.
Dr Marc Reichow, from the University of Leicester, said: “We looked at a time window of between 12.5 to 8 million years ago. We wanted to know how to identify these eruptions and find out how frequently they happened.”
The team found there were fewer volcanic events during this period than had been estimated, but these eruptions were far larger than was previously thought.
Dr Reichow added: “If you look at older volcanoes, it helps to understand what Yellowstone is likely to do.”
BBC © 2013
New Super Volcano Activity!
The giant plume of hot rock feeding the Yellowstone supervolcano may be even bigger than thought, scientists have discovered.
It's building quickly, but that doesn't mean doomsday eruption is imminent
The huge volcano under Yellowstone National Park has been rising at an unprecedented rate during the past several years, according to a new study.
In the ancient past, the Yellowstone volcano produced some of the biggest-known continental eruptions, but the recent rising doesn't mean another doomsday eruption is looming, scientists say.
The recent rising is unprecedented for Yellowstone's caldera — the cauldron-shaped part of the volcano — but it's not uncommon for other volcanoes around the world. The new study has simply revealed a more active caldera at Yellowstone than scientists realized.
"It's pretty exciting when you see something that's five times larger than what you've seen in the past," said Charles Meertens, director of the nonprofit UNAVCO facility in Boulder, Colo., which aids geoscience research. Meertens is a former postdoctoral fellow under one of the study's authors, Robert Smith of the University of Utah in Salt Lake City.
In 2004, the caldera was swelling at 2.8 inches a year in some parts, but the uplift has since slowed to a low of 0.2 inches a year, according to the study, which was published in the December edition of the journal Geophysical Research Letters.
Calderas rise just like an inflating bubble. The inflating could either be caused by magma rising and pushing up on the caldera, or the magma could be heating gases and hydrothermal fluids (the same fluids that spew from Yellowstone's Old Faithful geyser) and pushing them against the caldera, Meertens told OurAmazingPlanet. Whatever the exact mechanism, a rising caldera is not enough to signal an eruption.
"It's not a portent of doom," said Erik Klemetti, a volcanologist at Denison University in Granville, Ohio, who was not involved with the study. "It seems like these restless calderas are always sort of rising and falling, but that by itself doesn't mean it's about to erupt."
Volcanologists look at several indicators when deciding whether an eruption is looming, Klemetti said. Warning signs typically include an increase in earthquakes under the volcano, changes in the gases being emitted, change in the volcano's shape, and steam and heat escaping from the top.
No volcano eruption is expected imminently in Yellowstone National Park in the United States as speculated by some news reports, geophysicist Peter Cervelli said on Monday.
News reports both from the United States and some foreign countries said scientists were predicting that the world's largest super-volcano in Yellowstone National Park, one of America's most popular national parks, could erupt in the near future.
Reports said Yellowstone National Park's caldera has erupted three times in the last 2.1 million years and researchers monitoring it say there could be in for another eruption.
They said that the super-volcano underneath the Wyoming park has been rising at a record rate since 2004 - its floor has gone up three inches per year for the last three years alone, the fastest rate since records began in 1923.
Asked to comment on the speculation, Cervelli of the Yellowstone National Park Volcano Science Center, told Xinhua in an interview that the eruption of a big volcano is possible, but it is " extremely unlikely it will erupt in a near term." ...MORE!
Recent research from scientists shows that the super volcano below Yellowstone National Park could make two-thirds of U.S. land uninhabitable, disrupting thousands of flights, and forcing millions to leave their homes.
The last time this super-volcano erupted was 600,000 years ago, and it's due to erupt relatively soon. The volcano has been rising since 2004, but the scientists can't call a full out warning because they do not have an exact date of when the eruption might occur.
The University of Utah's Bob Smith, who is an expert in Yellowstone's volcanism told National Geographic, "It's an extraordinary uplift, because it covers such a large area and the rates are so high."
Smith went on to say, "At the beginning we were concerned it could be leading up to an eruption. Once we saw the magma was at a depth of ten kilometres, we weren't so concerned. If it had been at depths of two or three kilometre we'd have been a lot more concerned."
Yellowstone Has Bulged as Magma Pocket Swells | National Geographic - January 19, 2011
Some places saw the ground rise by ten inches, experts report.
Yellowstone National Park's supervolcano just took a deep "breath," causing miles of ground to rise dramatically, scientists report.
The simmering volcano has produced major eruptions—each a thousand times more powerful than Mount St. Helens's 1980 eruption—three times in the past 2.1 million years. Yellowstone's caldera, which covers a 25- by 37-mile (40- by 60-kilometer) swath of Wyoming, is an ancient crater formed after the last big blast, some 640,000 years ago.
(See "When Yellowstone Explodes" in National Geographic magazine.)
Since then, about 30 smaller eruptions—including one as recent as 70,000 years ago—have filled the caldera with lava and ash, producing the relatively flat landscape we see today.
But beginning in 2004, scientists saw the ground above the caldera rise upward at rates as high as 2.8 inches (7 centimeters) a year. (Related: "Yellowstone Is Rising on Swollen 'Supervolcano.'")
The rate slowed between 2007 and 2010 to a centimeter a year or less. Still, since the start of the swelling, ground levels over the volcano have been raised by as much as 10 inches (25 centimeters) in places.
"It's an extraordinary uplift, because it covers such a large area and the rates are so high," said the University of Utah's Bob Smith, a longtime expert in Yellowstone's volcanism. ... MORE!
Yellowstone Recent Status Report, Updates, and Information Releases.
December 2008 Yellowstone Earthquake And Ground Deformation Summary
Yellowstone seismicity increased significantly in December 2008 due to an energetic earthquake swarm that commenced on December 26. This swarm, a sequence of earthquakes clustered in space and time, is occurring beneath the northern part of Yellowstone Lake in Yellowstone National Park. As of this writing, the largest of these earthquakes was a magnitude 3.9 at 10:15 pm MST on Dec. 27. Through 5:00 pm MST on Dec. 31, the sequence had included 12 events of magnitude 3.0 to 3.9 and approximately 20 of magnitude 2.5 to 2.9, with a total of at least 400 events large enough to be located (magnitude ~1 or larger). National Park Service (NPS) employees and visitors have reported feeling the largest of these earthquakes in the area around Yellowstone Lake and at Old Faithful and Grant Village.
The hypocenters of the swarm events cluster along a north-south-trending zone that is about 7 km long. The vast majority of the focal depths are shallower than 5 km. It is not possible to identify a causative fault of other feature without further analysis.
Analysts are currently processing the backlog of seismic data from these events. The current analyst-processed catalog is believed to include all events of magnitude 2.5 and greater through Dec 31 at 5 pm MST, but hundreds of earthquakes remain to be processed. The total of more than 400 locatable events is based on automatically-determined locations and magnitudes for the swarm events.
The December 2008 earthquake sequence is the most intense in this area for some years. No damage has been reported within Yellowstone National Park, nor would any be expected from earthquakes of this size. The swarm is in a region of historical earthquake activity and is close to areas of Yellowstone famous hydrothermal activity. Similar earthquake swarms have occurred in the past in Yellowstone without triggering steam explosions or volcanic activity. Nevertheless, there is some potential for hydrothermal explosions and earthquakes may continue or increase in magnitude. There is a much lower potential for related volcanic activity.
The National Park Service in Yellowstone has been kept fully informed of the ongoing seismic activity via electronic means and by phone contacts with the University of Utah and the U.S. Geological Survey USGS). The Wyoming Office of Homeland Security is reviewing Earthquake Response Plans and monitoring seismic activity.
Earthquakes are a common occurrence in the Yellowstone National Park area, an active volcanic-tectonic area averaging 1,000 to 2,000 earthquakes a year. Yellowstone's 10,000 geysers and hot springs are the result of this geologic activity. A summary of Yellowstone's volcanic history is available on the Yellowstone Volcano Observatory web site.
The University of Utah operates a seismic network in Yellowstone National Park in conjunction with the National Park Service and the U.S. Geological Survey. These three institutions are partners in the Yellowstone Volcano Observatory. Seismic data from Yellowstone are transmitted to the University in real-time by radio and satellite links from a network of 28 seismographs in the Yellowstone area and are available on the web.
YELLOWSTONE NATIONAL PARK, Wyoming: A minor earthquake has rattled remote northeastern Yellowstone National Park.
The U.S. Geological Survey's National Earthquake Information Center in Golden, Colorado, says the magnitude 4.1 quake struck the park at 5:59 a.m. (1259 GMT) Tuesday.
The quake was centered about 15 miles (24 kilometers) north of Yellowstone's east entrance. Yellowstone is located mostly in Wyoming, but also small parts of Idaho and Montana.
USGS geophysicist John Bellini says the quake was strong enough to wake people up but it was probably not strong enough to cause much damage.
Yellowstone is a hotspot of geological activity and very small earthquakes occur in the park regularly.
Tsunami-like waves created by an earthquake may have triggered the world's largest known hydrothermal explosion some 13,000 years ago, a federal scientist says.
The explosion created the Mary Bay crater that stretches more than one mile across along the north edge of Yellowstone Lake. Debris from the explosion has been found miles away.
Lisa Morgan of the U.S. Geological Survey told a gathering of scientists over the weekend at Mammoth Hot Springs that an earthquake may have displaced more than 77 million cubic feet of water in Yellowstone Lake, creating huge waves that essentially unsealed a capped geothermal system.
Though much has been made in recent years of a possible eruption of Yellowstone's "super volcano," geologists studying the park have long said that the likelihood is greater for a large hydrothermal explosion.
Morgan said that over the last 14,000 years there have been 20 hydrothermal explosions in Yellowstone that mostly left craters bigger than football fields. They resulted in well-known Yellowstone landmarks such as Mary Bay, Turbid Lake and Indian Pond, all near the north edge of Yellowstone Lake.
The explosions happen when hot water just below the surface flashes into steam and breaks through the surface.
Smaller explosions in Yellowstone happen about once every two years but rarely when people are around or in danger, according to a 2007 hazard assessment produced by USGS.
In 1989, an explosion at Porkchop geyser at Norris Geyser Basin sent rocks and debris flying more than 200 feet.
But geologists are still trying to better understand the larger explosions that happen about once every 700 years in Yellowstone and have left behind the biggest hydrothermal explosion craters in the world.
At Mary Bay, Morgan said she thinks there were at least two big waves before the explosion. Evidence of those waves has been found more than 3 miles north of the lake's edge, she said.
The explosion's column may have reached more than a mile in the air and spread debris across some 18 square miles, she said.
"You would not want to be here when this occurred," Morgan said.
Predicting if or when another will happen remains difficult but it's worthy of continued study, scientists involved with Yellowstone's geology said.
"It's something we should take notice of," Morgan said.
A big blob of molten rock appears to pushing up remnants of an ancient volcano in Yellowstone National Park in Wyoming, scientists reported Friday.
They say no volcanic explosion is imminent – that already happened 642,000 years ago, creating the volcanic crater known as a caldera where part of Yellowstone Lake sits.
But satellite readings show just how volcanically active the area remains, the researchers reported in the journal Science.
From the middle of 2004 through 2006, the floor of the caldera rose 7 inches at a rate of 2.8 inches a year – the biggest rise ever measured, they reported.
“There is no evidence of an imminent volcanic eruption or hydrothermal explosion. That's the bottom line,” University of Utah seismologist Robert Smith said in a statement.
“A lot of calderas worldwide go up and down over decades without erupting.”
Yellowstone is North America's largest volcanic field, produced by what is known as a hotspot, a plume of hot and molten rock squirting up from 400 miles beneath the planet's surface.
Monstrous eruptions took place there starting 2 million years ago but activity bubbles along much more calmly now – akin to similar volcanic fields such as the Campi Flegrei just outside Naples in Italy.
Beneath the field lies what is known as a magma chamber, which is actually similar to a wet sponge in structure.
“Our best evidence is that the crustal magma chamber is filling with molten rock,” Smith said. “But we have no idea how long this process goes on before there either is an eruption or the inflow of molten rock stops and the caldera deflates again.”
Heat from the chamber warms the park's hundreds of hot springs and geysers, including “Old Faithful,” perhaps the world's best-known geyser.
Established in 1872 as the first U.S. national park, Yellowstone also stretches to parts of Montana and Idaho.
The Yellowstone "supervolcano" rose at a record rate since mid-2004, likely because a Los Angeles-sized, pancake-shaped blob of molten rock was injected 6 miles beneath the slumbering giant, University of Utah scientists report in the journal Science.
"There is no evidence of an imminent volcanic eruption or hydrothermal explosion. That's the bottom line," says seismologist Robert B. Smith, lead author of the study and professor of geophysics at the University of Utah. "A lot of calderas [giant volcanic craters] worldwide go up and down over decades without erupting."
The upward movement of the Yellowstone caldera floor -- almost 3 inches (7 centimeters) per year for the past three years -- is more than three times greater than ever observed since such measurements began in 1923, says the study in the Nov. 9 issue of Science by Smith, geophysics postdoctoral associate Wu-Lung Chang and colleagues.
"Our best evidence is that the crustal magma chamber is filling with molten rock," Smith says. "But we have no idea how long this process goes on before there either is an eruption or the inflow of molten rock stops and the caldera deflates again," he adds.
The magma chamber beneath Yellowstone National Park is a not a chamber of molten rock, but a sponge-like body with molten rock between areas of hot, solid rock.
Chang, the study's first author, says: "To say if there will be a magma [molten rock] eruption or hydrothermal [hot water] eruption, we need more independent data."
Calderas such as Yellowstone, California's Long Valley (site of the Mammoth Lakes ski area) and Italy's Campi Flegrei (near Naples) huff upward and puff downward repeatedly for decades to tens of thousands of years without catastrophic eruptions.
Smith and Chang conducted the study with University of Utah geophysics doctoral students Jamie M. Farrell and Christine Puskas, and with geophysicist Charles Wicks, of the U.S. Geological Survey in Menlo Park, Calif.
Yellowstone: A Gigantic Volcano Atop a Hotspot
Yellowstone is North America's largest volcanic field, produced by a "hotspot" -- a gigantic plume of hot and molten rock -- that begins at least 400 miles beneath Earth's surface and rises to 30 miles underground, where it widens to about 300 miles across. There, blobs of magma or molten rock occasionally break off from the top of the plume, and rise farther, resupplying the magma chamber beneath the Yellowstone caldera.
Previous research indicates the magma chamber begins about 5 miles beneath Yellowstone and extends down to a depth of at least 10 miles. Its heat powers Yellowstone's geysers and hot springs -- the world's largest hydrothermal field.
As Earth's crust moved southwest over the Yellowstone hotspot during the past 16.5 million years, it produced more than 140 cataclysmic explosions known as caldera eruptions, the largest but rarest volcanic eruptions known. Remnants of ancient calderas reveal the eruptions began at the Oregon-Idaho-Nevada border some 16.5 million years ago, then moved progressively northeast across what is now the Snake River Plain.
The hotspot arrived under the Yellowstone area sometime after about 4 million years ago, producing gargantuan eruptions there 2 million, 1.3 million and 642,000 years ago. These eruptions were 2,500, 280 and 1,000 times bigger, respectively, than the 1980 eruption of Mount St. Helens. The eruptions covered as much as half the continental United States with inches to feet of volcanic ash.
The most recent giant eruption created the 40-mile-by-25-mile oval-shaped Yellowstone caldera. The caldera walls have eroded away in many areas -- although they remain visible in the northwest portion of the park. Yellowstone Lake sits roughly half inside and half outside the eroded caldera. Many smaller volcanic eruptions occurred at Yellowstone between and since the three big blasts, most recently 70,000 years ago. Smaller steam and hot water explosions have been more frequent and more recent.
Measuring a Volcano Getting Pumped Up
In the new study, the scientists measured uplift of the Yellowstone caldera from July 2004 through the end of 2006 with two techniques:1. Twelve Global Positioning System (GPS) ground stations that receive timed signals from satellites, making it possible to measure ground uplift precisely.The measurements showed that from mid-2004 through 2006, the Yellowstone caldera floor rose as fast as 2.8 inches (7 centimeters) per year -- and by a total of 7 inches (18 centimeters) during the 30-month period, Chang says.
2. The European Space Agency's Envisat satellite, which bounces radar waves off the Yellowstone caldera's floor, another way to measure elevation change.
"The uplift is still going on today but at a little slower rate," says Smith, adding there is no way to know when it will stop.
Smith says the fastest rate of uplift previously observed at Yellowstone was about 0.8 inch (2 centimeters) per year between 1976 and 1985.
He says that Yellowstone's recent upward motion may seem small, but is twice as fast as the average rate of horizontal movement along California's San Andreas fault.
The current uplift is faster than ever observed at Yellowstone, but may not be the fastest ever, since humans weren't around for its three supervolcano eruptions.
Chang, Smith and colleagues conducted computer simulations to determine what changes in shape of the underground magma chamber best explained the recent uplift.
The simulations or "modeling" suggested the molten rock injected since mid-2004 is a nearly horizontal slab -- known to geologists as a sill -- that rests about 6 miles (10 kilometers) beneath Yellowstone National Park. The slab sits within and near the top of the pre-existing magma chamber, which resembles two anvil-shaped blobs expanding upward from a common base.
Smith describes the slab's computer-simulated shape as "kind of like a mattress" about 38 miles long and 12 miles wide, but only tens or hundreds of yards thick.
In reality, he believes the slab resembles a large, spongy pancake formed as molten rock injected from below spread out near the top of the magma chamber.
The pancake of molten rock has an area of about 463 square miles, compared with 469 square miles of land for the City of Los Angeles.
Smith and colleagues believe steam and hot water contribute to uplift of the Yellowstone caldera, particularly during some previous episodes, but evidence indicates molten rock is responsible for most of the current uplift.
Chang says that when rising molten rock reaches the top of the magma chamber, it starts to crystallize and solidify, releasing hot water and gases, pressuring the magma chamber. But gases and steam compress more easily than molten rock, so much greater volumes would be required to explain the volcano's inflation, the researchers say.
Also, large volumes of steam and hot water usually are no deeper than 2 miles, so they are unlikely to be inflating the magma chamber 6 miles underground, Smith adds.
Ups and Downs at Yellowstone
Conventional surveying of Yellowstone began in 1923. Measurements showed the caldera floor rose 40 inches during 1923-1984, and then fell 8 inches during 1985-1995.
GPS data showed the Yellowstone caldera floor sank 4.4 inches during 1987-1995. From 1995 to 2000, the caldera rose again, but the uplift was greatest -- 3 inches -- at Norris Geyser Basin, just outside the caldera's northwest rim.
During 2000-2003, the northwest area rose another 1.4 inches, but the caldera floor itself sank about 1.1 inches. The trend continued during the first half of 2004. Then, in July 2004, the caldera floor began its rapid rate of uplift, followed three months later by sinking of the Norris area that continued until mid-2006.
Smith believes that uplift of the middle of the caldera decreased pressure within rocks along the edges of the giant crater, "so it allowed fluids to flow into the area of increased porosity." That, in turn, triggered small earthquakes along the edge of the "pancake" of magma. The amount of hot water flowing out of the deflated Norris area is much smaller than the volume of magma injected beneath the caldera, Smith says.
The research was funded by the National Science Foundation, the U.S. Geological Survey and the Brinson Foundation.
Adapted from materials provided by University of Utah.
The orange shapes in this image represent the magma chamber -- a chamber of molten and partly molten rock -- beneath the giant volcanic crater known as the Yellowstone caldera, which is represented by the rusty-colored outline at the top. The red rectangular slab-like feature is a computer-generated representation of molten rock injected into the magma chamber since mid-2004, causing the caldera to rise at an unprecedented rate of almost 3 inches a year, according to a new University of Utah study. In reality, the injected magma probably is shaped more like a pancake than a slab. The two rusty circles within the caldera outline represent the resurgent volcanic domes above the magma chamber.
(Credit: Wu-Lung Chang, University of Utah)
According to the National Geographic, the Yellowstone caldera has been rising at a rate of approximately 3 inches every year since the middle of 2004, three times faster than any previous measurements.
Although the Supervolcano hasn’t produced any eruption for at least 70,000 years, it is still very active and most experts believe that it will erupt at some time in the future. Whether this will be a moderate eruption (comparable to Mount St. Helens), or something much larger and potentially more catastrophic globally, is impossible to predict.
The last major eruption at Yellowstone was 640,000 years ago, which created a caldera some 40 miles in width, but these have happened on a fairly regular basis over the last two million years, and it could be said that the next is overdue.
The current changes at Yellowstone were detected by global positioning system stations and radar instruments on an orbiting satellite, but Kenneth Pierce of the U.S. Geological Survey in Bozeman, Montana said “..the Yellowstone caldera has inflated and deflated about six to eight times without a volcanic eruption” during the last 14,000 years. Robert Smith, a geophysics professor at the University of Utah who co-authored the recent study agreed “Calderas go up and down” but “occasionally they burp”.
A large “burp”, as Robert Smith puts it, could produce catastrophic effects for the world population and a similar eruption of the Supervolcano in Toba (Indonesia) 75,000 years ago is believed to have wiped out 60% of the human population. On that occasion the Toba Supervolcano ejected almost three times as much material as the Yellowstone eruption did 640,000 years ago. However, the Yellowstone caldera can do much worse and this occurred 2.2 million years ago.
Indonesia has also seen some recent volcanic activity, and scientists are concerned that Mount Kelud might be on the verge of a devastating eruption. A number of volcanoes in the region have been spewing out hot ash, molten rock and dark smoke, including Anak Krakatao (Child of Krakatoa). Kelud killed more than 5,000 people following an eruption in 1919.
A large eruption could easily plunge the Earth into a “volcanic winter” and worsen the present climatic changes we are experiencing. Some have suggested that these “changes” might even be connected with Global Warming, and if the cause is originating from space, this may well be true.
Earthside Comments: We've been particularly interested in this subject for some time. What follows is some of the information upon which the Discovery Channel movie is based.
Over the past two million years, the Yellowstone supervolcano has erupted every 600,000 years. It was 640,000 years ago when it last exploded. Another eruption, geologically speaking, is therefore, threatening.
Five miles beneath Yellowstone, lies an immense pool of red hot magma. Fed from the Earth's mantle, it has been growing. This reservoir of magma and gas is now 31 miles long, 19 miles wide, and six miles deep. The building pressures must be enormous.
The Yellowstone "hot spot" is considered the foundation of a rare "supervolcano." It is estimated that a supervolcano would erupt with the power at least 1000 times greater than that of an 'ordinary' volcano.
The eruption 640,000 years ago created an extremely large crater - the caldera - that today comprises a major portion of the center of the park.
Signs of increased volcanic activity have recently been observed in and around Yellowstone National Park. The north part of Yellowstone Lake has bulged by nearly 170 feet over the past 50 years. The lake has spread into forest on one side of the lake as the surface beneath the water has inflated.
A massive eruption of the Yelowstone supervolcano would be catastophic for North America and would also result in years of freezing temperatures for the rest of the planet as volcanic dust and ash obscured the warmth of the sun.