A team of geoscientists from the University of Edinburgh, UK, has discovered an extensive volcanic range beneath West Antarctica’s massive ice sheet.
Location map of subglacial volcanoes identified by van Wyk de Vries et al across the West Antarctic Rift System. Image credit: van Wyk de Vries et al, doi: 10.1144/SP461.7.
The identified volcanoes range in height between 330 and 12,630 feet (100-3,850 m), with an average relief of 2,037 feet (621 m), including 29 structures over 3,280 feet (1 km) tall.
Their diameter ranges between 2.8 and 36.3 miles (4.5-58.5 km), with an average diameter of 13.2 miles (21.3 km).
“We identified 138 volcanoes, 91 of which have not previously been identified, and which are widely distributed throughout the deep basins of West Antarctica,” the researchers explained.
“They are especially concentrated and orientated along the 1,864-mile (3,000 km) central axis of the West Antarctic Rift System.”
“The range has many similarities to East Africa’s volcanic ridge, which is currently acknowledged to be the densest concentration of volcanoes in the world,” the scientists noted.
In their research, they remotely surveyed the underside of the ice sheet for hidden peaks of basalt rock, like those of other volcanoes in the region whose tips push above the ice.
They analyzed the shape of the land beneath the ice using measurements from ice-penetrating radar, and compared the findings with satellite and database records, as well as geological information from aerial surveys.
“It is fascinating to uncover an extensive range of volcanoes in this relatively unexplored continent,” said team member Dr. Robert Bingham, of the University of Edinburgh’s School of GeoSciences.
“Better understanding of volcanic activity could shed light on their impact on Antarctica’s ice in the past, present and future, and on other rift systems around the world.”
“Antarctica remains among the least studied areas of the globe, and as a young scientist I was excited to learn about something new and not well understood,” added team member Max Van Wyk de Vries, a student at the University of Edinburgh’s School of GeoSciences.
“After examining existing data on West Antarctica, I began discovering traces of volcanism. Naturally I looked into it further, which led to this discovery of almost 100 volcanoes under the ice sheet.”
The results do not indicate whether the volcanoes are active, but should inform ongoing research into seismic monitoring in the area.
The findings will help geoscientists understand how volcanoes can influence long-term fluctuations in the ice sheet, and could also help improve understanding of how the continent has changed during past climates.
“Volcanic activity may increase if Antarctica’s ice thins, which is likely in a warming climate,” the authors said.
A paper reporting this discovery is published in the Geological Society Special Publications series.
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Maximillian van Wyk de Vries et al. A new volcanic province: an inventory of subglacial volcanoes in West Antarctica. Geological Society, London, Special Publications 461; doi: 10.1144/SP461.7
