Giant Sink Holes, measuring 260 feet wide in Siberia, Russia are likely caused by melting ice or permafrost, according to University of Alaska geophysicist Vladimir Romanovsky. At first, many speculated that those mysterious sinkholes where cause by either extraterrestrials or military weapons testing.
One unique concept of the sinkholes is that it actually erupted outside, tossing dirt around the rim. Vladimir Romanovsky explains that natural gas could have caused pressure to build as the water collected in an underground cavity, and the dirt was eventually expelled.
The sink may be several years old, due to the face that there are plants around the crater, but in order to get an exact age, more analysis must be conducted. More sinkholes may begin to appear, as the climate continues to change.