Mystery of Siberia's 200ft-deep craters solved: Enormous holes were formed...

Russian scientists say mystery giant holes suddenly appearing in northern Siberia were caused by dramatic gas eruptions, a process previously 'never observed'.

Russian scientists have spent months examining enormous craters which have appeared in the Yamal region of Siberia. The one shown above is among the most famous - known as B1 - and has been found to be 60 metres deep. The reserachers say

  • Russian scientists say mystery giant holes suddenly appearing in northern Siberia were caused by dramatic gas eruptions, a process previously 'never observed'.
  • A new expedition this week to several craters dotting the energy-rich Yamalo-Nenets reindeer region region found evidence they were previously pingos, mounds with an inner ice core common in Arctic and sub-Arctic regions.
  • Warming over a number of years triggered melting and the resulting empty space inside the ice humps became filled with natural gas, mainly methane, which eventually triggered eruptions.

 Another of the craters, known as B2 (shown above) is surrounded by several smaller craters, all of which have filled with water. This is thought to have been caused by a mud volcano combined with the melting of ice beneath a pingo

Some scientists have expressed concern at the holes erupting close to major gas extraction plants in the Yamal region. However, Professor Vasily Bogoyavlensky (shown above being interviewed in front of crater B1, who has been leading the research, insists there is no reason to panic. While he warns there are likely to be more craters appearing, they are unlikely to pose a serious threat

  •  Professor Vasily Bogoyavlensky, who led the latest expedition, examined the most famous crater - known as B-1 - which is 18 miles from Bovanenkovo gas field.

Scientists believe the craters formed as a result of ice beneath the surface melting and releasing gas into the void left behind. As temperatures have warmed and gas levels have increased, the natural gas erupted out of the ground with violent results

  •  It was first noticed last year, causing a flurry of interest around the world and speculation on how this phenomenon was caused, ranging from meteorites, to stray missiles, to UFOs from outer space.

Researchers have been studying the craters, which show no signs of charring or burning around the edge, and are already forming into lakes. The image above shows scientists and journalists on the edge of the crater B1 in the Yamal region of Russia

  • Scientists were this week surprised to find that echo-sounding equipment showed the crater to be more than 200 feet (60 metres) deep, significantly more than previously believed, and large enough 'to fit a multistorey building'.
  • The hole is already almost full of water after the melting of the winter snow cover. When it was visited last year, its base was far shallower - essentially a lake is beginning to form.
  • 'We can now [explain] more confidently about the process that led to the formation of the famous Yamal crater B-1,' he told The Siberian Times. 'Initially it was a pingo.'
  • A pingo is a mound of earth-covered ice found in the Arctic that can reach up to 230 ft (70m) in height and up to 2,000 ft (600m) in diameter.
  • In this case warming from geothermal heat caused this pingo to 'thaw and its half melted ice core [became] filled with gas that originates from the depth through cracks and faults in the ground.
  • 'We know for sure that there is a fissure in the ground on this spot, probably even two intersecting cracks.
  • 'Gullies around the spot confirm this. Through the cracks, deep natural gas got into the melting ice core.
  • '[Gas] filled it and the pingo erupted.
  • 'It was also heated by a stream of warmth coming from the bowels of the earth through the cracks.'
  • The process is different than usual because normally pingos thaw and collapse, forming craters and then lakes.'
  • With the B-1 crater and others known as B-3 and B-4 'we see that the pingo erupts due to the gas, which fills its core.

Scientists have spent the past few months visiting the craters in an attempt to learn more about how they formed. The image above shows researchers in the depths of crater B1 after it had been frozen and stabilised by the harsh Siberia

This picture of crater B1 shows how it looked last year shortly after it formed. It has since begun filling with water and is turning into a lake.

More info: dailymail