The funnel of the crater is about 16.5 metres deep, not including an earthen rampart on the surface, formed in the blowout, of several metres in height.
Gas hydrates are ice-like forms of water containing gas molecules, notably methane. They exist in permafrost regions such as northern Siberia, but also under the oceans in some parts of the world.
'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 metres down, and on the layer close to the surface', said scientist Vladimir Potapov before the latest expedition. '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.'
He stressed: '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. That means that the temperature there was higher than usual.'
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