A Super Volcano in Yellowstone
A Super Volcano
In 1971, a paleontologist accidentally discovered the fossil bones of a large herd in Nebraska. The remains were dated to 10 million years ago.
The animals were in the prime of their lives, and it was assumed that a natural phenomenon had been responsible for their death. All of the bones were affected by a disease, which according to further investigation was associated with volcanic ash.
However, the area wasn't volcanic, and no known volcano was situated in the immediate vicinity. Normally, during an eruption a volcano spews lava and ash, and with violent outbursts this ash can be spread over a few hundred miles.
Further investigation revealed that the only volcanic eruption around that time had been the Bruno Drawbridge , located in northern Idaho. But that location is about 1,600 km to the west...
The eruption was examined in its turn, and samples of soil and ash from all over America were compared. It appeared that after this explosion about half of America had been covered with on average two meters of ash !
Such a violent eruption was hundreds of times more violent than a "normal" volcanic eruption, and had never before been seen. A name for the phenomenon was soon found, this was a SUPER VOLCANO !
What is a Super Volcano ?
In a typical volcano, magma pushes itself to the surface, usually after a landslide, through a "chimney". Lava flows from the crater and gradually forms the volcano's typical conical mountain. At the same time, volcanic ashes are thrown up by the gases from the magma, that escape in the air.
With the Super Volcano everything is different.
Magma will be pushed to the surface through a chimney, but en route it piles up in a huge chamber, deep under the surface.
This "bubble" is gradually filled with liquid magma and super-hot gases.
The "boiler" gradually comes under enormous pressure, and it slowly pushes up the mile-thick layer of earth above it.
After a break in the earth layer, usually by an earthquake or a landslide, a rift is formed along which the entire contents of the chamber are explosively spewed out. After the eruption, no typical mountain remains, but rather a major depression or subsidence of land, because the now empty chamber collapses under the weight of the overlying mass. Such a depression is called a Caldera .
Scientists started investigating the entire earth's surface, and they found traces of another "recent" Super Volcano, the Toba in Sumatra, that exploded about 74,000 years ago.
In 1973, a geologist discovered that parts of Yellowstone National Park came under water, whereas previously they had been dry.
This led to extensive measurements, and these were compared with previous measurements from 1923.
This in turn led to the discovery that one side of the lake had been pushed up for more than 74 cm (2 1/2 ft), which caused the lake to move and flood new sections!
This could be an indication that a magma chamber was being formed, deep below the surface.
In Yellowstone Park, scientists went in search of the caldera that would have been formed after an eruption.
They only managed to find it after the NASA provided special aircraft that took high-altitude photos of the area. Then the reason why no caldera had been found became immediately apparent. The elliptical depression was 70 km long by 30 km wide , or almost as large as the entire Yellowstone Park !...
Samples of the ash layers in the soil were taken to date the eruption. To their great surprise they found traces of not one but three Super Eruptions ; respectively 2 million, 1.2 million, and 600,000 years ago. The eruptions at this location seemed to occur with a certain regularity, at intervals of 600,000 to 800,000 years. And the last eruption dated from 600,000 years ago...
Several seismographs were installed and the shock waves from mild earthquakes were thoroughly examined. They revealed that there was a magma chamber at eight kilometers below the Earth's surface.
Now things started to look grim and the whole area was re-examined meticulously with 22 seismographs, to obtain more information about this chamber.
Eventually, its size could be determined : 50 km long by 22 km wide and 10 km high !
A Super Eruption
This is an appallingly powerful powder keg , with a content of more than 10,000 cubic kilometers, located under about one third of the park.
Scientists were in shock, and they tried to calculate the potential power and impact of an eventual eruption.
They visited the Greek island of Santa Rini, where 3,500 years ago an eruption had occurred, not really a Super Volcano, but still with a small magma chamber.
The pumice of this eruption included heavy boulders weighing dozens of tons, that had been blown away like pebbles...
In an English laboratory a super-eruption was imitated, on a scale of one billionth. Volumes of acetone and pine resin were mixed in a flask, put under pressure and strongly heated. Acetone actually possesses many of the properties of volcanic gas, and pine resin shows a strong resemblance to magma.
When the mixture was heated, the situation remained pretty much unchanged until the acetone suddenly ignited. It worked as a detonator for the pine resin, which explosively expanded to a near-gas and caused a large mini-eruption.
Armed with these scientific data, they again examined the super-volcano Toba in Sumatra, to verify the effects of the eruption. The Caldera that was formed after the eruption is 100 km wide by 67 km long. It was calculated that about 3,000 cubic kilometers of material were thrown up, and soil samples were found in the Indian Ocean with 35 cm (1 ft) of ash from this eruption, more than 2,500 km away !...
This eruption also propelled large quantities of sulfur dioxide in the atmosphere, which in turn caused a volcanic winter, and global temperatures dropped by five degrees Celsius !
By coincidence, the results of this research came to the ears of any other scientific team, that examines DNA worldwide, and studies the changes through the generations. They specialized their research on the Mitochondria , the engines in our cells, that exist alongside the individual DNA.
These Mitochondria are only passed on by the mother, and they have their own genetic structure. The mutations of these genes are statistically very predictable, and they can therefore display a sort of "lifeline" of the entire human race.
Oddly enough, this team had reached the strange conclusion that a gap existed in the diversity of these genes. Between 70,000 and 80,000 years ago the number of different genes had been reduced enormously, insofar that of the entire worldwide race of Homo Erectus during this period, only 5,000 to 10,000 members remained.
Therefore there had to have been a natural disaster, which had nearly eradicated the entire human race. The two theories were combined in a startling statement, namely that the eruption of a Super-Volcano had nearly wiped out all human life ! These are of course matters for scientific controversy...
Future Eruption ?...
Another team tried to mathematically calculate the effects of a Super Explosion of the Yellowstone magma bubble, based on the geological data.
They reached the conservative conclusion that the explosion would spew out gas and ash between 40 and 50 km high, and more than 1,000 km away...
As luck would have it, the area itself is sparsely populated. But still, tens of thousands would be killed by the eruption.
Worse news is that the extremely fertile Great Plains, which are North America's breadbasket but also the rest of the world's basket, would entirely be covered with ashes, which would instantly kill all agricultural yields.
Furthermore, the enormous volume of ash in the atmosphere would cause a volcanic winter around the globe, and large parts of Europe would become infertile.
The number of victims of such an enormous natural disaster cannot even approximately be estimated, especially since there are no scientific observations of this phenomenon to base comparisons on.
The scientific teams gloomily came to the conclusion that a Super Volcano eruption in Yellowstone is not a question of IF , but rather of WHEN ...
reference : Read about another Super Volcano at Crater Lake, OR !
Actually it is the remains of former Mount Mazama,
More by this Author
The Rise and fall of the French Colonial Empire in North America
The French and Indian War : the culmination of 74 years of wars between the French and the English.
ohn Pemberton, the inventor of the Coca Cola syrup, had become addicted to morphine. Being a brilliant chemist, he searched for a cure to his addiction, or at least a more modern substitute. Necessity is the mother of...