21-02-13 Methane Crater in Siberia
Excerpt: In June 2017, a reindeer herder of the Yamal peninsula in northwest Siberia, Russia, reported a loud blast and smoke rising from the ground. Later, a crater with a diameter of 7 meters (25 ft) and almost 20 meters (65 ft) deep, surrounded by blocks and chunks of ice and soil, was discovered at the supposed explosion site. Another similar, even more powerful explosion had occurred in 2013, when a blast was heard over a distance of 62 miles.
"Mysterious Craters In Siberia Linked To Melting Permafrost," David Bressan, Forbes, Sept. 16, 2020