Hundreds of craters on the seafloor of the Arctic Ocean was found to be created by a methane gas explosion 12,00 years ago. The finding of ancient Arctic methane explosion is necessary to understand the cause of the events, because the similar event may possibly happen again.

The findings of the ancient Arctic methane explosion has been published in the Science Magazine vol. 356/6341. A multinational team of scientists has discovered that craters in the Barents Sea, situated in the north of Norway and Russia were created by the huge rise of methane that exploded in a catastrophic explosion thousands of years ago.

Professor of marine geology and geophysics at the University of Tromsø (UiT) the Arctic University of Norway, Karin Andreassen is a lead researcher for the study. She first discovered the craters as the result of ancient Arctic methane explosion in the 1990's. In this recent research, she and the team used the latest technology to map the seafloor more accurately. They discovered a huge number of craters in the large area.

“We realized that there were hundreds of them," Professor Andreassen said in an interview with Newsweek regarding the trace of Arctic methane explosion that she found. "We could also get detailed images of them. We got seismic data showing the structure underneath, and the links with deeper hydrocarbon sources.”

The team discovered the beginning of Arctic methane explosion started from the end of the last Ice Age when the Barents Sea was covered in an ice sheet that presses down the sea floor. When the ice began to subside, the methane reservoir below the earth floor became unstable and started to decompose and moved upward. The methane settled in the shallow depth in a big concentration, creating huge mounds of concentrated gas in form of craters.

SImilar to thousands of years ago, the craters may trigger another Arctic methane explosion when they collapse. It is because the craters are extremely vulnerable to the change in temperature and pressure. Watch the illustration of the craters at the bottom of the Arctic sea floor below: