![]() ![]() That allows molten magma to rise toward Earth’s surface. A rift zone forms where some of the tectonic plates of Earth’s crust are spreading or splitting apart. This mega-volcanic province is likely associated with the West Antarctic Rift zone, explains Bingham, an author of the study. This newfound province stretches across a span as large as the distance from Canada to Mexico - some 3,600 kilometers (2,250 miles). Together, they form one of the planet’s largest volcanic provinces, or regions. Most lie in a region called Marie Byrd Land. These volcanoes are hidden beneath the vast, slowly moving West Antarctic Ice Sheet. The new study is a great example of how online data and images can help people make discoveries in inaccessible places, Siddoway now says. Although she studies Antarctic geology, she did not take part in this project. That left 91 as brand new to science.Ĭhristine Siddoway works at Colorado College in Colorado Springs. Of those, 47 had been identified earlier as buried volcanoes. In all, 138 cones matched all of the criteria for a volcano. The researchers also looked at images of the area taken by satellites. These can give scientists clues to their type and origins. For example, they studied data showing the density and magnetic properties of the rocks. They used several methods that can help confirm the presence of a volcano. The geologists then cross-checked the cone shapes they had spotted with Bedmap2 against other types of data. The researchers used this data to discover 91 previously unknown volcanoes buried under thousands of meters of ice. Bedmap2 compiles many types of data to reveal the detailed land surface beneath Antarctica’s thick ice. One example is ice-penetrating radar, which can “see” through the ice to reveal the shape of the land below. Created by the British Antarctic Survey, it combines different types of data about Earth. They used an online data set called Bedmap2. But Van Wyk de Vries and his colleagues looked instead at the land surface beneath the ice. Previous scientific studies in the area had focused on the ice. The team described its findings last year in a Geological Society of London Special Publication. No surface clues, however, reveal the existence of most of them. Small bumps on the ice mark the site of some buried volcanoes, he says. “The fact that there was a large number of undiscovered volcanoes in Antarctica that had escaped attention was honestly surprising to all of us, especially given that many of them are huge,” he notes. Some peaks were large - up to 1,000 meters (3,280 feet) high and tens of kilometers (at least a dozen miles) across, says Van Wyk de Vries. These were 91 new volcanoes hiding beneath ice as much as 3 kilometers (1.9 miles) thick. Together, they confirmed what Van Wyk de Vries thought he saw. Then he showed them to Andrew Hein and Robert Bingham. Cone shapes, he knew, are typical of volcanoes. ![]() But then, he says, he started seeing familiar-looking cone shapes. ![]()
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