Thursday, 27 October 2011

Toba Lake: The Largest Volcanic Eruptions Ever

Toba Lake
Location of the largest volcanic eruptions in the last 25 million years, which almost destroyed the entire human race began in 1980, Mount St. Helens in Washington spit a plume of smoke 80,000 feet high, people were killed and 57,200 houses destroyed, 27 bridges, 15 miles of track and 185 miles from the highway. It was deadly and destructive eruption most economically volcanic history of the United States.

 For comparison, the largest volcanic eruption in recorded historic times, the eruption of Tambora in 1815. He was eighty times more powerful than Mount St. Helens and spat about 100 km3 of rock and the entire northern hemisphere is dark and cold for all of 1816, making it the "year without summer" , as we have known. But compared to the case who participated in North Sumatra, Indonesia around 73,000 years ago, this was as good as nothing.

Known as the event they Toba ejected almost 2800 km3, or 28 times the largest volcanic eruption in historical memory, and more than two thousand times more powerful than Mount St. Helens. It was like the Yellowstone supervolcano "big" sister, and when these mega-colossal volcanic levels 8 - the highest rating on the volcanic explosivity index - burst was the largest volcanic eruption in the last 25 million years.

 It can have almost destroyed the human race.

When the volcano, he filed six meters of ash on parts of Malaysia and a layer 15 cm thick ash on the Indian subcontinent and acid rain fell for many years. The temperature of the planet suddenly dropped 3-5 ° C and after a few (from ice cores from Greenland), it immediately starts the next ice age world.

It turns out that this enormous environmental disaster with signs of massive decline in human population results in the collapse of a genetic bottleneck. According to the theory of the Toba catastrophe, 6 to 10 years of volcanic winter resulting destroyed most of the vegetation in the area, where people live and may have reduced the population so few breeding pairs in 1000.

There is some good evidence for this genetic bottleneck, and many geneticists believe that the evidence that all living descendants despite their apparent diversity, a very small population, perhaps between 1000 to 10,000 breeding pairs in about 70,000 years. It is well known that the East African chimpanzee, orang-utan in Borneo, the Central Indian macaques and tigers, all recovered from the population bottelnecks about the same time. All this seems to fit perfectly with the theory super-volcano Toba Toba catastrophe, and the event.

But as it is still science, nothing is pure or simple statements and contradictory is just as strong. For the conflicting testimony are similar tools in India below and above the ash layer to live relatively unchanged, and the fact that non-human hominids such as Homo erectus soloensis, Homo floresiensis, Homo neanderthalensis, which all came to be adversely affected by, however, the volcano seems unprecedented disaster proof of genetic bottlenecks survived. 

Whether it is almost annihilated mankind or not, for all those who were alive 75,000 years the eruption of Toba must be sure that the end of the world to have taken place.

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