That Hole at the End of the World

Methane explosion? Meteorite crater? Scientists baffled by gigantic 262ft hole that has appeared at Siberia's 'End of The World'

An urgent expedition will leaves tomorrow to probe a giant crater that has appeared in gas-rich northern Siberia.

Extraordinary aerial images show a mysterious hole which experts say may be up to 262 feet wide, in the Yamal Peninsula of northern Russia.

'A scientific team has been sent to investigate the hole and is due to arrive at the scene on Wednesday,' The Siberian Times has reported.

An urgent expedition will leaves tomorrow to probe a giant crater that has appeared in gas-rich northern Siberia.

Extraordinary aerial images show a mysterious hole which experts say may be up to 262 feet wide, in the Yamal Peninsula of northern Russia.
'A scientific team has been sent to investigate the hole and is due to arrive at the scene on Wednesday,' The Siberian Times has reported.
. . .
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.

Well, certainly global warming is involved in the sense that everything that happens on the ground in Siberia now is a consequence of the glaciers melting at the end of the last glacial maximum, about 14,000 years ago.  But, I mean, who would expect a circular hole to form in a landscape that looks like this from the air:

https://maps.google.com/maps/ms?msid=214346639281780692613.0004367766678de7629d5&msa=0&ll=69.314925,70.026855&spn=0.387106,1.234589

In a few years, when the harsh winters erode the rim, and the ground water fills the hole, it will be just another circular pond.