Yellowstone: Too close for comfort?

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Boulder lies more than 400 miles from Yellowstone. Would we actually be affected by such an eruption?

As the crow flies, Boulder lies more than 400 miles from Yellowstone. Would we actually be affected by such an eruption? The short answer, says U.S. Geological Survey (USGS) volcanologist Lisa Morgan Morzel, is “most likely.”

From painstaking mapping, geologists know that large volumes of lava as well as pyroclastic flows—raging torrents of hot gas and rock fragments—poured from Yellowstone during past super-eruptions.

The displacement of the water in Lake Yellowstone.

A ship that had sank about 30 feet down 50 years ago was now sitting on top of dry land. This was due to a giant lava gas bubble forming under the entire lake, much like a blister, pushing the entire lake upwards and displacing the water. Eventually, this bubble will burst. How long it will take is anyone guess, but it will happen and bubbles like this is normally a precursor to an eruption.

In addition, huge amounts of ash, blasted high into the atmosphere, drifted as far as Iowa and Louisiana before settling, like snowflakes, to the ground.




But much of this ash has since been carted off by rivers or shifted by gusts of wind, so its thickness—and hence the associated hazard level—has been difficult for scientists to gauge.

A group of USGS geologists, tired of being unable to answer the interminable questions about how much ash would fall in a given area, applied a new model of ash dispersion to the Yellowstone region. The results show that under current weather patterns, a super-eruption comparable in size to the one that occurred 640,000 years ago would blanket nearly the entire nation with ash, contaminating water supplies and farmland and almost completely shutting down communications and air travel.

While local impacts would depend upon how long the eruption lasted, as well as the winds at that time of year, the average of all the model simulations indicates that Boulder would be coated with 2.5 to 5.2 inches of ash—enough to create treacherous driving conditions, short out transformers, cause respiratory problems, and clog the engines of the Super-volcano snowmobiles, but probably not enough to block water and sewer lines or cause buildings to collapse.

Those conditions would more likely occur in Casper, Wyo., or Billings, Mont., which would be buried beneath 3 to 6 feet of ash.

The three super-eruptions occurred 2.1 million, 1.3 million, and approximately 630,000 years ago, forming the Island Park Caldera, the Henry’s Fork Caldera, and Yellowstone calderas, respectively.

The Island Park Caldera super-eruption (2.1 million years ago), which produced the Huckleberry Ridge Tuff, was the largest and produced 2,500 times as much ash as the 1980 Mount St. Helens eruption.

The next biggest super-eruption formed the Yellowstone Caldera (~ 630,000 years ago) and produced the Lava Creek Tuff. The Henry’s Fork Caldera (1.2 million years ago) produced the smaller Mesa Falls Tuff but is the only caldera from the Snake River Plain-Yellowstone hotspot that is plainly visible today.

Non-explosive eruptions of lava and less-violent explosive eruptions have occurred in and near the Yellowstone caldera since the last super-eruption.

The most recent lava flow occurred about 70,000 years ago, while a violent eruption excavated the West Thumb of Lake Yellowstone around 150,000 years ago.




With a small submersible robot, the researchers found a canyon just east of Stevenson Island which was 390 ft. deep. Prior to this finding, the deepest spot in the lake was thought to be 320 ft., at West Thumb.

Researchers also found that the conditions in Yellowstone Lake are similar to those that occur near the famous hydrothermal vents on the Pacific Ocean’s mid-ocean ridge. Nutrient- and mineral-rich submarine fountains support incredible plant and animal communities, including bacterial mats, sponges, and earthworms.

Yellowstone: Too close for comfort?

During late summer, Yellowstone Lake becomes thermally stratified with each of several water layers having a different temperature. The topmost layer rarely exceeds 66°F, and the lower layers are much colder.

October 2016 : The amount of heat flowing out of hydrothermal vents in the floor of Yellowstone Lake appears to be much higher than previously thought.

Hot water

The last time measurements were taken in Yellowstone Lake was about 40 years ago. At that time, scientists didn’t have the detailed mapping of the lake floor like this year’s researchers could access. By precisely knowing where hot vents were located on the lake bottom, the HD-YLAKE crew could guide a remote vehicle into position to insert a temperature probe to measure heat flow.

The highest temperature recorded was around 340 to 350 degrees.

Smaller steam explosions occur as well: Yellowstone Lake contains the largest known hydrothermal explosion crater in the world, located in Mary’s Bay. The crater from that eruption, which occurred about 13,800 years ago, measures a mile and a half across.

Currently, volcanic activity is exhibited via numerous geothermal vents scattered throughout the region, including the famous Old Faithful Geyser, plus recorded ground swelling indicating ongoing inflation of the underlying magma chamber.

U.S. Geological Survey (USGS) seismology reports conclude that a massive swarm of earthquakes swept through the park on Friday triggering more than 60 separate events in which seismographs spiked to magnitudes of up to 5.0.

The quake was centered near West Yellowstone, but was also felt by people in Gardiner and Bozeman.

Yellowstone: Too close for comfort?

“As of 10 a.m. Friday morning we had located a total of 235 earthquakes in the area,” said Jamie Farrell, University of Utah research professor of seismology. And Yellowstone gets about 1,500 to 2,000 earthquakes every year. That means 1 out of ever 8 earthquakes Yellowstone gets in a year happened in just a few hours of one day.

Not only was Thursday’s quake the largest in the current swarm, it was the largest in the area since March 30, 2014, when a 4.8 magnitude earthquake hit near Norris Geyser Basin, according to a news release from the University of Utah Seismograph Station. But USGS downgrded this earthquake from a M5. to a M4.5 the to a M4.4.

What we do know is that there is enough magma down there that could fill up 14 Grand Canyons to the brim, and the sudden release of all of this – in the form of lava, pyroclastic flows, and ash fallout – would amount to nothing less than a regional disaster, and possibly even a global one.

Experts fear that the super-volcano is long overdue for an eruption capable of wiping out a vast amount of human, animal, and plant life in the Continental United States.

Scientists currently believe that there’s a 10% chance that a “supervolcanic Category 7 eruption” could take place this century, as pointed out by theoretical physicist Michio Kaku who appeared on a segment for Fox News.

The grey haired physicist told Shepard Smith that the “danger” we are now facing with the caldera is that it’s long overdue for an eruption which Kaku said could “rip the guts out of the USA.”

Kaku said that a “pocket of lava” located under the park has turned out to be twice as big as scientists originally thought.

In December 2008, continuing into January 2009, more than 500 quakes were detected under the northwest end of Yellowstone Lake over a seven-day span, with the largest registering a magnitude of 3.9.

A swarm in January 2010 after the Haiti earthquake and before the Chile earthquake. With 1,620 small earthquakes between January 17, 2010 and February 1, 2010, this swarm was the second largest ever recorded in the Yellowstone Caldera.

The largest of these shocks was a magnitude 3.8 which occurred on January 21, 2010.This swarm reached the background levels by February 21. On March 30, 2014, at 6:34 AM MST, a magnitude 4.8 earthquake struck Yellowstone, the largest recorded there since February 1980

Scientist concur that the last eruption of the caldera took place some 640,000 years ago.

The U.S. is currently under contract with at least 4 countries all of which have agreed to house displaced U.S. citizens in the unfortunate event the Yellowstone super-volcano were to erupt.

Hundreds of billions of dollars were paid to foreign governments to facilitate the agreement which spans a ten year period from its signing, ending in 2024.

The U.S. plan for relocation was formulated after a recent scientific analysis of the park revealed that Yellowstone’s super-volcano has the potential to violently erupt within the next 10-years as noted by others including the famous astrophysicist Michio Kaku.

Yellowstone: Too close for comfort?

Chris Newhall of the United States Geological Survey and Stephen Self of the University of Hawaii developed the Volcanic Explosivity Index (VEI) in 1982.

It is a relative scale that enables explosive volcanic eruptions to be compared with one another. It is very valuable because it can be used for both recent eruptions that scientists have witnessed and historic eruptions that happened thousands to millions of years ago.

The primary eruption characteristic used to determine the volcanic explosivity index is the volume of pyroclastic material ejected by the volcano. Pyroclastic material includes volcanic ash, tephra, pyroclastic flows, and other types of ejecta. The height of the eruption column and the duration of the eruption are also considered in assigning a VEI level to an eruption.

The VEI 8 eruption with the greatest volume of ejecta known is the Wah Wah Springs eruption that occurred in what is now the state of Utah, about 30 million years ago. It is estimated to have produced over 5500 cubic kilometers of ejecta in about a week.

The largest explosive eruptions that have been documented to date have been rated at VEI 8. Could eruptions larger than Toba, Yellowstone, and other VEI 8 events occur? Does Earth have the ability to produce a blast capable of launching the 10,000 cubic kilometers of ejecta needed to rate a VEI 9 eruption?

It is possible that evidence for a VEI 9 eruption exists and is buried in the geologic record. Eruptions that large would be very rare events, but it is impossible to say that eruptions that large have never occurred. If an eruption that large were to occur in the future, it would be a significant threat to life on Earth.

Only four volcanic eruptions in “recent” times (that is, in the last 10,000 years) have been assigned a VEI of 7. They are:

Tambora, Indonesia (1815)
Baitoushan, China-Korea border, (about 1050)
Kikai, Japan, (about 4350 BC)
Crater Lake, Oregon, USA, (about 4895 BC)

Every thousand years or so, a volcano erupts somewhere on the planet with enough power to significantly alter the global climate for years afterwards.

Prodigious quantities of dust and sulphur aerosols are ejected into the atmosphere, preventing the Sun’s rays from reaching the ground.

Universal crop failures occur, temperatures drop dramatically, and living creatures across the globe die off in large numbers. Such an event occurred in 1815, on the island of Sumbawa in Indonesia – the explosion of the great Tambora volcano.

The longer term effects of Tambora were felt across the globe. In addition to the large quantities of ash, rocks and dust ejected by the volcano, over 200 million tonnes of sulphur dioxide gas were propelled into the stratosphere. This had the effect of limiting the amount of sunlight that reached the ground, so that temperatures, particularly across the Northern Hemisphere, began to fall dramatically4. Monsoon season was interrupted in India, possibly leading to a deadly outbreak of cholera that insinuated its way across the globe. Europe experienced widespread crop failures just as it was recovering from the effects of the Napoleonic Wars. Ireland had its first great famine. Devastating floods hit China. In North America, 1816 is remembered as ‘the year without a summer’, when snow fell during June and frost was still widespread during the month of July.

A massive eruption of Yellowstone would mean that just about everything within a 100 mile radius of Yellowstone would be immediately killed.

In the event of a full-scale eruption of Yellowstone, virtually the entire northwest United States will be completely destroyed and the blast could also potentially dump a layer of volcanic ash that is at least 10 feet deep up to 1,000 miles away. Nothing, plant or animal can live through that.

Mary Greeley News
www.marygreeley.com

Credit http://geology.com/stories/13/volcanic-explosivity-index/

http://www.bellrock.org.uk/misc/misc_year.htm

Yellowstone earthquake swarm hits entire park, more than 60 on Friday alone