The Denver Post

LAND IN ARCTIC BLOWS “LIKE A BOTTLE OF CHAMPAGNE”

- — © The New York Times Co.

A natural phenomenon first observed by scientists just six years ago and now recurring with alarming frequency in Siberia is causing the ground to explode spontaneou­sly and with tremendous force, leaving craters up to 100 feet deep.

When Yevgeny Chuvilin, a Moscow-based geologist with the Skolkovo Institute of Science and Technology, arrived this summer at the rim of the latest blast site, called Crater 17, “it left quite an impression,” he said.

The pit plunged into darkness, surrounded by the table-flat, featureles­s tundra. As Chuvilin stood looking in, he said, “It was making noises. It was like something alive.”

While initially a mystery, scientists have establishe­d that the craters appearing in the far north of western Siberia are caused by subterrane­an gases, and the recent flurry of explosions is possibly related to global warming, Chuvilin said.

Since the first site was found in 2014, Russian geologists have located 16 more on the Yamal and Gydansk peninsulas, two slender fingers of land stretching into the Arctic Ocean.

Chuvilin said the conditions causing the explosions, which are still not fully understood, are probably specific to the geology of the area, as similar craters have not appeared elsewhere in Siberia or in permafrost zones in Canada and Alaska that are also affected by global warming.

The explosions occur underneath small hills or hummocks on the tundra where gas from decaying organic matter is trapped undergroun­d. Contained beneath a layer of ice above and permafrost all around, the gas creates pressure that elevates the overlying soil. The explosions occur when the pressure rises or the ice layer thaws and breaks suddenly.

With warmer summers, the active layer is deepening, potentiall­y melting and weakening the ice over the gas deposits. The gases causing the explosions, Chuvilin said, may have built up to their current pressure tens or hundreds of thousands of years ago.

Another possibilit­y is that methane trapped in deeper layers of the permafrost in a crystallin­e, ice-like form is reverting to its gaseous state, possibly because of effects of global warming. In this theory, rising pressure rather than thawing on the surface is causing the gas pockets to burst.

“It goes off like a bottle of Champagne,” Chuvilin said.

Newspapers in English

Newspapers from United States