
When frozen, the accessible parts of crater (pictured from below) are around 54ft (16.5 metres) deep, and scientists captured these latest remarkable images by using climbing gear to reach a frozen lake 34ft (10.5 metres) at the bottom. It is thought the crater was formed when heating from underground fissures released gas hydrates causing the dramatic blowout
The photographs were released as it was revealed scientists are monitoring satellite images to check for other similar holes in northern Russia in a desperate attempt to understand their origin.
And, for the first time, Siberian scientists have used climbing gear to reach a frozen lake 34ft (10.5 metres) deep in the hole to carry out tests.













Comment: See also: Russian scientists suggest Siberian exploding holes 'are the key to Bermuda Triangle'