Same phenomenon of discharge of gas hydrates 'led to crater formation in Russia and disappearance of ships in Atlantic'.
'The main element - and this is our working theory to explain the Yamal crater - was a release of gas hydrates'. Picture: The Siberian Times
The craters - two in Yamal and one on the Taymyr peninsula - were revealed during the summer, leading to urgent analysis by scientists as well as a wave of speculation suggesting the cause was aliens from outer space, meteorites, or stray missiles.
Now respected Science in Siberia journal has come up with a coherent explanation for the northern craters and - sensationally - links it to the notorious Bermuda Triangle phenomenon, where ships and aircraft have disappeared under strange circumstances between Bermuda, Florida and Puerto Rico.
Heating from above the surface due to unusually warm climatic conditions, and from below, due to geological fault lines, led to a huge release of gas hydrates, say the scientists from the Trofimuk Institute of Petroleum-Gas Geology and Geophysics in Novosibirsk.
Science in Siberia call the craters 'a distant relative of Bermuda triangle'. Pictures: The Siberian Times
They subjected one of the two known craters in Yamal - a peninsula known to locals as 'the end of the world' - to detailed scrutiny.
'The main element - and this is our working theory to explain the Yamal crater - was a release of gas hydrates. It turned out that there are gas hydrates both in the deep layer which on peninsula is several hundred meters down, and on the layer close to the surface,' said scientist Vladimir Potapov.
Gas - notably methane - is trapped in the frozen hydrates under the permafrost and beneath some oceans.
'There might be another factor, or factors, that could have provoked the air clap. Each of the factors added up and gas exploded, leading to appearance of the crater. 'The crater is located on the intersection of two tectonic faults. Yamal peninsula is seismically quiet, yet the area of the crater we looked into has quite an active tectonic life', Potapov said.
Crucially, the surface ice and upper layers of permafrost were exposed to 'a much warmer summer than usual', as Tyumen scientist Marina Leibman earlier noted. Igor Yeltsov, the Trofimuk Institute's deputy head, stressed: 'There is a theory that the Bermuda Triangle is caused by gas hydrates.'
He explained: 'They start to actively decompose with methane ice turning into gas. It happens in an avalanche-like way, like a nuclear reaction, producing huge amounts of gas. That makes the ocean heat up, and ships sink in waters which are infused with huge amounts of gas. This leads to the air becoming supersaturated with methane, creating an extremely turbulent atmosphere, leading to aircraft crashes'.
Trofimuk Institute of Petroleum-Gas Geology and Geophysics' researches work at Yamal crater. Pictures: Media Centre of SBRAS
Science in Siberia call the craters 'a distant relative of the Bermuda triangle'. The experts conducted tomographic, radiometry and magnetic surveys at the site.
'We checked magnetic and radiation backgrounds, and found no abnormalities there,' said Oleg Kushnarenko, chief engineer on the four and a half day mission.
Potapov stressed the need for further study.
'We have to continue works by all possible means. We all have to keep suggesting hypotheses and testing them, because the crater itself is an incredibly interesting from the scientific point of view, and secondly because things like this crater can make a strong impact on the development of Yamal's infrastructure.
'This was a recce trip that would allow us set agenda for the next trip, or trips, and give us basic understanding of what could have happened. We must also pay attention to areas where the same thing might potentially happen'.
The current theory should carry 'health warnings', he emphasised. 'We are still in the process of interpreting them. One thing is clear - it was not a single reason that led to the gigantic explosion. It was like a bouquet of flowers, where each of them added something and together they led to the explosion - but at this stage we are unable to say how each of these 'flowers', or factors, that came together, actually worked'.
Watch July 2014 expeditition to Yamal crater
The expedition was initiated by both director of the institute, academician Mikhail Epov, and the head of Nadym Gazprom Mining, Sergey Menshikov.
'It is quite a rare case of a state corporation and a scientific body uniting resources,' said Dr Yeltsov, approvingly. 'Our partners provided us with helicopters and special equipment, allowing us to carry all necessary researches in the area with a high possibility of methane ignition. We pulled some money from other projects and got the rest of equipment together.'
Chief engineer Kushnarenko said: 'We didn't manage to do some things either because of the lack of time, or security reasons. For example, there was a great temptation to go down the crater, but the Institute didn't give a go ahead saying it was too risky.'
The crater they studied is in the Yamalo-Nenets Autonomous, some 30 kilometres from the Bovanenkovo gas field. It is up to 70 metres deep, but the hole is not as wide as initial reports suggesting it was between 50 and 100 metres wide.
See previous stories on the craters:
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