At https://www.livescience.com/planet-earth/geology/mystery-of-siberias-giant-exploding-craters-may-finally-be-solved … this is a subject that has fascinated many people, from geologists to global warmers, and from the guy in the pub to the kids asking difficult questions at home. Giant exploding craters are a feature of the Russian permfrost – in the Yamal and Gydon peninsulars. Some eight 160 feet deep craters, or 50 metres in EU speak, have been exciting the Internet for a couple of decades. They are apparently unique to Yamal and Gydon in Russia, and have spawned a variety of theories to explain what is going on. These range from meteor impacts to natural gas blow-outs. One popular idea connected them with ancient lakes that once bubbled with methane as they dried out. Unfortunately, the craters are found in a variety of geological settings – and not all of them could have been paleo-lakes.
The distributiion of the craters point to an explanation peculiar to Yamal and Gydon, which is common sense thinking. The common denominator is natural gas, and methane, as the area is part of the West Siberia hydrocarbons province – with reserves of 265 trillion cubic metres. A lot of gas. The gas field is capable of heating the permafrost and conributing to a thinning of the ice load overhead. Interestingly, the authors say the permafrost in the area likely formed after the retreat of glaciers – more than 40,000 years ago. What glaciers were they? They also mention early Holocene warming, as well as cooling episodes such as the Little Ice Age of the 16th and 17th cenuries AD. The mid Holocene warm period was much warmer than today, they add, so these things must have occurred at various times in the past and are not peculiar to the 20th and 21st centuries. In other words, local heat from gas deposits provides the means to create melt from an underground source – which then explodes at the surface. Simple when it is explained – without the global warming mantra playing too much of a role.