Methane explosion? Meteorite crater? Scientists baffled by gigantic 262ft hole that has appeared at Siberia's 'End of The World'
Anna Kurchatova from the Sub-Arctic Scientific Research Centre, thinks the crater was formed by a mixture of water, salt and gas igniting an underground explosion, a result of global warming.
Gas accumulated in ice could have mixed with sand beneath the surface, and then mixed with salt.
Global warming may have caused an 'alarming' melt in the under-soil ice, released gas and causing an effect like the popping of a Champagne bottle cork, Ms Kurchatova suggests.
Yamal, a large peninsula jutting into Arctic waters, is Russia's main production area for gas supplied to Europe.