which two islands are australias active volcanoes on, and what are they called?

Ashley

The two islands are Heard Island, with a volcano called Big Ben, and McDonald island, with a volcano that I don't know the name of. The following article was published in the Melbourne Herald. Later, a reply complained that the volcano on McDonald wasn't recently "discovered" - they've known about it for a long time. Discovery of the century ... smoke rises from McDonald Island, Australia's second active volcano. Photo by DICK WILLIAMS * Scientists investigating a newly active volcano south-west of the Australian mainland believe billowing smoke and steam plumes are the tail-end of an eruption which has occurred far beneath the sea. The volcano, detected in March when smoke and steam were seen rising dramatically from the bare hills of remote McDonald Island, 4,500km south-west of Perth, is the first active volcano to be discovered in the Southern Hemisphere for at least a century. In the main event, thought to have occurred in late December or early January, the volcano's undersea magma chamber was probably breached by seawater. In the aftermath, molten rock fused into rafts of pumice and steam clouds were sent billowing kilometres into the sky. Previously believed to have been inactive for more than 35,000 years, McDonald is Australia's second active volcano after nearby Big Ben on Heard Island. It probably shares the same source, a magma plume deep in the Earth's core-mantle boundary, according to geochemist Professor Ken Collerson. Professor Collerson, of the University of Queensland, yesterday showed the Australian Antarctic Research Jubilee Symposium evidence of the sub-sea eruption in pumice stone he recovered from Heard beach shortly after seeing McDonald. The analysis of isotopes of strontium, neodymium and lead showed the pumice must have originated from McDonald. Excited scientists have viewed McDonald's activity from the national research ship Aurora Australis, which passed by chance earlier this year, and from fishing trawlers. Professor Collerson and others saw steam and smoke rising from McDonald at high speed from points on the island's north-west. "I have seen a lot of active volcanoes and this really looked to me typically like a volcano's flank. The main crater, I think, would be under the sea." Scientists initially thought the steam plume, revealed in weather satellite images taken of the Heard Island area, had come from Big Ben, which erupts about every 10 years. But when Australian Antarctic fisheries scientist Dr Dick Williams passed by, he saw steam and smoke clouds rising, small black lava flows, and a sulphur-like deposit on the volcano's summit. "Not for hundreds of years has a new volcano been found in the Southern Hemisphere ... and it would be one of only a handful around the world," said Professor Collerson, who has been closer to McDonald than anyone, venturing to within two kilometres of the island. "Plume volcanoes are unpredictable. It's impossible to say when McDonald will erupt again, and it could be very grim for anyone on the island when it erupts.

Sincerely,
Scott Rowland

Other Categories Other Questions
To VolcanoWorld