Specialist research teams are set to visit the site of an 80m sinkhole that has suddenly appeared in the Yamal Peninsula in northern Russia in a bid to establish the cause.
The sinkhole is located around 30km from the Bovanenkovo gas field and one theory that has been put forward is that the natural gas caused a migratory collapse from hundreds of meters below ground. The theory will be one that the expedition organised by the Yamal authorities, that includes two experts from the Centre for the Study of the Artic and one from Cryosphere Institute of the Russian Academy of Sciences, will be considering once it arrives on site.
Peter Brett Associates geotechnics and geohazards expert Clive Edmonds speculated: “The usual suspects when a hole appears are limestone or gypsum or dissolution of the ground. The other most frequent is a manmade mine working. There’s a possibility that the extraction of gas and the movement of ground round an underlying fault line caused something like this to appear – there may be a link to the extraction process.
“It’s more likely to be deep-seated and may have collapsed over some old works – which may or may not fit with the geology – or something related to gas extraction. If something was going to move, bearing in mind the reservoirs of gas are normally hundreds of metres deep underground, you’d only see a connection to the surface through some deep-seated fault.
“I’m not aware that this is a widespread phenomenon or of any holes appearing due to gas or oil extraction anywhere else in the world. Either a very special set of circumstances have contrived to form this or it is more mundane, like mine workings.”
Edmonds also pointed out only other sinkholes of this scale worldwide have been reported in the karstic soil system of Florida and South African mining and dewatering areas.