The Yamal Craters
Later explainedSummary
In 2014 a helicopter crew flying over the Yamal peninsula found a hole in the tundra. It was enormous, almost perfectly circular, tens of metres across, with sheer sides going down into the permafrost.
There was no impact. There was no burning. And the soil that had been in the hole was lying all around the rim.
That last detail is the whole answer. Material thrown outward means the force came from below. Something under the ground exploded.
Since then more than twenty of them have been found, and the most unsettling finding is not the craters. It is how quickly they stop looking like craters.
What is documented
The first. In July 2014, a large crater was identified on the Yamal peninsula, whose name in the language of the Nenets means, roughly, the end of the world. It was reported worldwide and was immediately attributed by the internet to meteorites, missiles and aliens.
The shape. The craters are near-circular, with steep walls, and depths that have been measured in the tens of metres. There is no scorching and no melt.
The rim. Ejected soil and blocks of frozen ground lie scattered around the opening, sometimes for a considerable distance.
This is diagnostic. An impact crater is excavated from above and its ejecta has a characteristic distribution. A sinkhole is a collapse: material falls in, and there is no rim of thrown debris. Yamal craters have thrown material outward and upward, which means the energy came from underneath.
The number. More than twenty have now been identified across the Yamal and Gydan peninsulas.
They disappear. Within a few years, a crater fills with water. Once it has, it is very difficult to distinguish from the many thousands of ordinary thermokarst lakes that cover the region.
This has an implication that is more interesting than the craters themselves: there may be a great many older ones, and they may be all around, indistinguishable from lakes, and nobody would ever have known.
Leading explanations
A gas explosion from beneath the permafrost. Established in outline; the details are an active field.
The Siberian permafrost is not a solid block. It contains cryopegs: lenses of unfrozen, extremely saline water trapped within the frozen ground. Beneath and within it there are also deposits of methane, some of it in the form of gas hydrates, which are stable only under particular conditions of pressure and temperature.
As the permafrost warms, those conditions change. Gas accumulates. Pressure builds beneath the frozen cap, which acts as a lid. A mound forms at the surface, and grows, and eventually the cap fails.
The ground is blown out. The gas escapes. What is left is a hole with its contents lying around it.
The dominant gas is methane. Russian teams, including work led by Vasily Bogoyavlensky, have measured very high methane concentrations at the sites, and the mechanism has been refined since 2014, with more recent work examining the specific role of the cryopegs and the osmotic pressures within them.
What was ruled out. Meteorite impact: no impact signature, and the ejecta pattern is wrong. Missiles or military activity: nothing in the debris, and the phenomenon is now known from more than twenty sites. Sinkhole collapse: the material is outside the hole, not at the bottom of it.
What the popular version gets wrong
"They appeared out of nowhere and nobody knows why." The mechanism was substantially worked out within a few years by Russian permafrost scientists, who went to the sites and measured the gas.
"They are sinkholes." They are the opposite of sinkholes. A sinkhole falls in. These blew out.
"It is a new phenomenon." It is a newly observed phenomenon, which is a different claim. Because the craters turn into lakes within a few years, it is entirely possible that this has been going on for a long time and that the region is dotted with the healed scars of it. Nobody was flying over the Yamal with a camera in 1940.
"It is a curiosity." It is a visible, physical, photographable consequence of a warming Arctic, releasing a potent greenhouse gas, in a region that holds a very great deal of it. The craters are the interesting part only until you ask what came out of them.
Current status
Later explained. Gas accumulation beneath a permafrost cap, followed by explosive failure of the cap. The mechanism is established. The precise triggering conditions, and the role of the cryopegs, remain a live research question, and new craters continue to appear.
The registry keeps this record because of what the ejecta rim did to the case. One glance at where the soil went ruled out every exotic explanation and pointed at the only remaining direction, which was down.
Sources
- Bogoyavlensky, V. I. and colleagues, field investigations of the Yamal and Gydan craters and measurement of methane concentrations at the sites, from 2014.
- Subsequent research literature on gas-emission craters, cryopegs, and permafrost gas hydrates in northwestern Siberia.
- Satellite and aerial survey records of the Yamal peninsula.
Last reviewed: July 2026. Records are provisional. Where the evidence changes, the entry changes. Found an error? Tell us.