Sea volcano blows its top 300km off NZ coast

Antaletriangle · 03-13-2009, 11:49 AM

http://www.stuff.co.nz/science/22571...m-off-NZ-coast
There has been an enormous eruption in an underwater volcano about 300 kilometres from the Bay of Plenty. Using underwater mapping devices, scientists have found evidence of the eruption by the Rumble III Volcano near the Kermadecs. Rumble III, which is part of the 250-kilometre South Kermadec Ridge, rises 2300 metres from the sea floor. Until 2007, its summit was within about 200m of the sea surface. However, scientists on a research ship that has just spent two weeks investigating underwater volcanoes have found a "startling change" in the shape of the summit, which has reduced in height by about 100m. The volcano has endured a "fairly catastrophic" eruption. A map made in 2007 showed an 800m-wide crater near the top, but the new map now shows the crater had been filled and the nearby summit cone had shrunk. "This suggests there has been a major eruption that collapsed the summit cone and filled the adjacent crater." The eruption is consistent with the fact that a number of the 90 submarine volcanoes along the Kermadec Arc are highly active. Some of the volcanoes along the 2000 kilometre underwater chain, which runs northeast of New Zealand between the Bay of Plenty and Tonga, are as big as Mt Ruapehu. (map)

Rumble III, which is part of the 250-kilometre South Kermadec Ridge, rises 2300 metres from the sea floor. Until 2007, its summit was within about 200m of the sea surface.

However, scientists on a research ship that has just spent two weeks investigating underwater volcanoes have found a "startling change" in the shape of the summit, which has reduced in height by about 100m.

Cornel de Ronde, co-chief GNS scientist on the voyage, said the volcano had endured a "fairly catastrophic" eruption.

A map made in 2007 showed an 800m-wide crater near the top, but the new map now showed the crater had been filled and the nearby summit cone had shrunk.

"This suggests there has been a major eruption that collapsed the summit cone and filled the adjacent crater," Dr de Ronde said.

03-13-2009, 11:49 AM	#1
Antaletriangle Avalon Senior Member Join Date: Sep 2008 Location: U.K. Posts: 3,380	Sea volcano blows its top 300km off NZ coast http://www.stuff.co.nz/science/22571...m-off-NZ-coast There has been an enormous eruption in an underwater volcano about 300 kilometres from the Bay of Plenty. Using underwater mapping devices, scientists have found evidence of the eruption by the Rumble III Volcano near the Kermadecs. Rumble III, which is part of the 250-kilometre South Kermadec Ridge, rises 2300 metres from the sea floor. Until 2007, its summit was within about 200m of the sea surface. However, scientists on a research ship that has just spent two weeks investigating underwater volcanoes have found a "startling change" in the shape of the summit, which has reduced in height by about 100m. The volcano has endured a "fairly catastrophic" eruption. A map made in 2007 showed an 800m-wide crater near the top, but the new map now shows the crater had been filled and the nearby summit cone had shrunk. "This suggests there has been a major eruption that collapsed the summit cone and filled the adjacent crater." The eruption is consistent with the fact that a number of the 90 submarine volcanoes along the Kermadec Arc are highly active. Some of the volcanoes along the 2000 kilometre underwater chain, which runs northeast of New Zealand between the Bay of Plenty and Tonga, are as big as Mt Ruapehu. (map) Rumble III, which is part of the 250-kilometre South Kermadec Ridge, rises 2300 metres from the sea floor. Until 2007, its summit was within about 200m of the sea surface. However, scientists on a research ship that has just spent two weeks investigating underwater volcanoes have found a "startling change" in the shape of the summit, which has reduced in height by about 100m. Cornel de Ronde, co-chief GNS scientist on the voyage, said the volcano had endured a "fairly catastrophic" eruption. A map made in 2007 showed an 800m-wide crater near the top, but the new map now showed the crater had been filled and the nearby summit cone had shrunk. "This suggests there has been a major eruption that collapsed the summit cone and filled the adjacent crater," Dr de Ronde said.