A team of scientists unearthed a volcanic region previously hidden under ice sheets, with the geologist who led the team warning of destabilising consequences.
Edinburgh University researchers uncovered almost 100 volcanoes - with the highest almost as tall as Switzerland's 3,970-metre Eiger.
Geologists think the region, which sits two kilometres below ice in west Antarctica, will dwarf east Africa's volcanic ridge, which is rated as the world's densest concentration of volcanoes, according to Daily Mail.
Glacier expert Robert Bingham, who helped author the paper, warned The Guardian the range could have worrying consequences.
"If one of these volcanoes were to erupt it could further destabilise west Antarctica's ice sheets.
"Anything that causes the melting of ice - which an eruption certainly would - is likely to speed up the flow of ice into the sea.
"The big question is: how active are these volcanoes? That is something we need to determine as quickly as possible."
The Edinburgh volcano survey, featured in the Geological Society's special publications series, examined the underside of the ice sheet for hidden peaks of basalt rock similar to those produced by the region's other volcanoes.
Over the past century, explorers have reported sightings of their tips, which reach above the ice.
The survey team's youngest member, Max Van Wyk de Vries, is a volcano fanatic who wouldn't stop wondering how many tips lie below the ice.
An undergraduate at the university's school of geosciences, he set up the project with Dr Bingham.
They used ice-penetrating radar carried by planes and land vehicles to analyse measurements made by previous surveys and survey strips of west Antarctic ice.
Dr Bingham explained the results were compared with satellite and database records and geological information from aerial surveys.
"Essentially, we were looking for evidence of volcanic cones sticking up into the ice."
After collating the results, the team reported 91 previously unknown volcanoes, adding to 47 others discovered over the previous century by explorers.
These newly discovered volcanoes range from 100 to 3,850 metres high.
All are covered in ice, sometimes in layers that are more than 4km thick.
Dr Bingham was shocked to find the active peaks concentrated in the west Antarctic rift system, which stretches 3,500km from Antarctica's Ross ice shelf to the Antarctic peninsula.
"We were amazed. We had not expected to find anything like that number.
"We have almost trebled the number of volcanoes known to exist in west Antarctica.
"We also suspect there are even more on the bed of the sea that lies under the Ross ice shelf, so that I think it is very likely this region will turn out to be the densest region of volcanoes in the world, greater even than east Africa, where mounts Nyiragongo, Kilimanjaro, Longonot and all the other active volcanoes are concentrated."
The volcanic activity could have crucial implications for Earth. If one erupts, it could further destabilise ice sheets in the region, where global warming has already had an impact.
Dr Bingham's fear is that the Antarctic ocean's meltwater outflows will cause sea levels to rise.
"We just don't know about how active these volcanoes have been in the past.
"The most volcanism that is going in the world at present is in regions that have only recently lost their glacier covering - after the end of the last ice age. These places include Iceland and Alaska.
"Theory suggests that this is occurring because, without ice sheets on top of them, there is a release of pressure on the regions' volcanoes and they become more active."
Significant warming caused by climate change in west Antarctica has already affected its ice sheets.
If they reduce significantly, this could release pressure on volcanoes lying below.
This would lead to eruptions that could further destabilise ice sheets and enhance sea level rises, something Dr Bingham is keen to monitor.
"It is something we will have to watch closely."