Syberian sinkholes

Giant sinkholes which started appearing in
Yamal Peninsula, Russia last year remain a
mystery to scientists investigating this
phenomena around the world.

The best-known sinkhole measures almost 85 feet in inside diameter and is 160-feet deep — enough to fit a 15-story building in between its uncannily straight walls of ice. The mysterious sinkholes have promptly generated a slew of theories about their appearance.

Theories about what's causing them are numerous... from UFO's to natural gas which is abundant in this region. Locals, however, are not looking for scientific explanation. They prefer to believe that giant, perfectly round craters, have a 'connection to another world'.

Vasily Bogoyavlensky, head of the geological and geophysical lab working on the site, told RT he believes gas is the unique cause of these phenomena, because the gas, thanks to gravity, tries to come to the surface, searches for fractures and cracks, and goes through to the surface.

In other words, the blowouts were caused by gas coming to surface from several hundred yards to several miles deep underground.
According to Bogoyavlensky, the sinkholes may be far older than they appear — but it's possible nobody noticed them before.

Some scientist suppose, global warming could
have played a role, sapping the permafrost that
contains methane in the ground.