Climate change, they say, remains the most likely explanation for that phenomenon. The topography of the bedrock around the volcano indicates that meltwater would flow off the mountain's flanks and beneath the glacier, lubricating its base and speeding up the movement of the ice.Ĭorr and Vaughan point out that heat from the volcano could not cause the widespread thinning of the ice that is taking place across Western Antarctica. In this study we present: (1) new major and trace element compositions of glass and minerals from 38 lava bombs erupted from Erebus volcano between 19, and (2) new major and trace element whole-rock compositions of 11 lavas erupted from the summit region in the last 17 ka. This, say the researchers, could explain why the nearby Pine Island Glacier has experienced sudden accelerations toward the sea twice in the past few decades. The same process could be happening in the ice around the Hudson Mountains volcano. Mount Casertz stands some 600 metres high, but the only sign of its existence from the surface is a large depression in the ice above caused by heat from the active cone melting the ice. The elliptical shape of the layer, the fact that it thins towards the edges, and the fact that all of the debris was deposited at the same time led the researchers to conclude that this must be a fine sheet of volcanic debris that was propelled into the air by an eruption and settled back down on the ice around the volcano.Īlthough the new volcano is probably the most recent one to have exploded, researchers have known about another subglacial volcano in Antarctica for some time. They deduced that instead of marking the bottom of the ice sheet, the signal comes from a layer of debris, 0.3 millimetres at its thinnest, suspended in the ice. But it is so strong that previous researchers had thought that it must be bedrock and mapped it as the bottom of the ice sheet on that assumption.Ĭorr and Vaughan's radar allowed them to see through the signal to the real bedrock beneath. The radar signal had been noticed before. This project will develop an interdisciplinary geophysics/geochemistry laboratory on Mount Erebus, for the purpose of pursuing basic research on the eruption. Hugh Corr and David Vaughan of the British Antarctic Survey made their discovery using a powerful radar system.įlying over the Hudson Mountains, which separate the East and West Antarctic ice sheets, they detected a layer of debris the size of New Hampshire in the US (23,000 square kilometres), between 100 and 700 meters beneath the surface of the ice.
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