Video shows methane leaking from beneath an Arctic river after spectacular eruption
Gas bubbles from waters filling crater hole on Yamal peninsula two months after volcanic-style explosion in thawing permafrost.
By Anna Liesowska
Scientists say it is 'clean' methane but they are now analysing whether it comes from deep in the earth or nearer the surface, perhaps through existing fissures and faults.
The Seyakha eruption is the most recent of a series of crater or funnel formations recently noticed in northern Siberia. It was the only one witnessed at close hand by humans. Some 700 sites in the region are reported to be vulnerable to eruptions.
The phenomenon is seen as highlighting the release of greenhouses gases due to thawing permafrost which under relatively recent global warming capped the methane beneath the surface.
A key concern is the impact of such eruptions on industrial facilities including pipelines in the Yamal region, one of the world's largest natural gas supply locations.
'We have gathered some charred sand and grass from Seyakha, but actually no analysis is needed to confirm what is obvious: there definitely was burning.
'We did not find any similar traces of burning at the Yerkuta funnel, but here the eruption was in winter, so pieces of ice, soil and ground fell onto the snow, it melted in spring and all traces might just disappear.
'We found pebbles there, but we cannot say 'yes' or 'no' regarding burning.
'The same is true about the Bovanenkovo funnel.'
This is the most famous and spectacular of the craters found in recent years.
'We found pebbles, but no traces of burning,' he said.
This means that burning may occur - or not - during such eruptions.
'What is important - we now know for sure that the gas can burn during such eruptions,' he said.
Such 'burning' increases the risk for industrial energy facilities.
Gas companies are monitoring sites vulnerable to such eruptions.
These are believed to be geological phenomenon known as pingos where beneath which permafrost is thawing.
'It is all about monitoring,' said Dr Sinitasky.
'I know that oil and gas producing companies have maps of such objects and monitor them constantly.
'I have heard that for example Gazprom-Dobycha Yamburg make punctures and release gas to avoid eruption risk.
'When I was working at VNIIGAZ, I made a map of such objects for Gazprom.'
He said: 'The companies are very interested in minimising risks, they do not need any accidents, so they make maps and observe these objects very closely.
'As for the general map of such objects... The Institute of Oil and Gas Problems keeps a database on sites being discovered using satellite data.
The Earth Cryosphere Institute probably has its own database.
'We provide them with data on new palaeo-craters because it is important to study these things in an historical context.'
He believes that the phenomenon is 'unique' the the geological conditions on the Yamal and Taimyr peninsulas, where .
'We now know that these objects form when there is a coincidence of a thick layer of permafrost and thick sedimentary cover of 3.5 to 5 kilometres,' he said.
'This is why we can observe pingos in Yakutia or Alaska, but they do not explode.'
He told The Siberian Times: 'We are observing such a phenomenon for the first times in history, that is why we call them new,...
'I do not exclude that such objects could form earlier, it's just that they were not observed.
'For example ornithologist Alexander Sokolov has an old picture, showing geologists sitting on a breastwork.
'It is similar to what we see on the Bovanenkovo and Yerkuta funnels.
'Why were they not observed earlier?
'First of all there was no such (industrial) infrastructure as we have now.
'But also we see now how they change their shape very fast - turning to lakes, are covered with plants, so maybe geologists or locals just did not have a chance to see them soon after the eruption.
'Perhaps they just did not pay attention.
'In addition, I suppose that now, because of climate change, such objects appear more often then previously.'