The mysterious hole that opened up a fortnight ago in Siberia’s Yamal Peninsula just got even more mysterious.
Reindeer herders have now found two more, one of which is estimated to be half the size of the original, which was 30 metres across, but just as perfectly formed.
One of the craters is on the same peninsula as the first one:
The other is on the Taymyr Peninsula. The Taymyr crater is smaller (around four metres in diameter) but up to 100m deep, as the herders discovered by nearly falling into it.
Russian scientists traveled to the site of the original hole but were still left scratching their heads as to what caused it.
The Siberian Times reports the most favoured theory is one involving “melting permafrost due to climate change, causing a release of methane gas, which then forces an eruption.”
Dr Chris Fogwill of the University of New South Wales weighed in for the Sunday Morning Herald this week, suggesting it might be a “pingo” – a large chunk of underground ice that can create a hole when it melts.
Others are pointing some 40 kilometres away at a huge gas extraction plant at Bovanenkov, claiming shale oil mining and fracking were the cause.
Andrey Plekhanov, senior researcher at the Russian Scientific Centre of Arctic Research, said satellite mapping imagery was showing the holes were most likely formed some time in the past two years.
He said years 2012 and 2013 were “relatively hot for Yamal”, adding some weight to the global warming theories, but more study was needed before that could be linked to the holes.
Meteorite strikes have been ruled out because up to 80 per cent of the crater appear to be made of ice, which scientists discovered by lowering acamera down the largest hole on Yamal Peninsula.
An icy lake also sits at the bottom of that hole.
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