Scientists on board the CSIRO’s research ship the Investigator have taken rare pictures of an eruption of the remote Big Ben volcano. Big Ben on the sub-Antarctic Heard Island is the highest mountain on Australian territory. The neighbouring McDonald Islands are also home to an active volcano.
The voyage’s Chief Scientist, Professor Mike Coffin from the Institute of Marine and Antarctic Studies, said the eruption came as a surprise. “Seeing vapour emanating from both of Australia’s active volcanoes and witnessing an eruption on Mawson Peak have been an amazing coda to this week’s submarine research,” he said.
“We have 10 excited geoscientists aboard Investigator, and our enthusiasm has spread to our 50 shipmates.” Jodi Fox from the University of Tasmania who is also onboard, is doing a PhD on Heard Island volcanism. “To see lava emanating from Mawson Peak and flowing down the flank of Big Ben over a glacier has been incredible,” she said.
The remote Australian Territory of Heard and McDonald Islands is 4,100 kilometres south west of Perth and 1,750 kilometres north of Australia’s Antarctic base at Davis Station. Scientists on the voyage are studying the link between active volcanoes on the seafloor and the mobilisation of iron, which supports life in the Southern Ocean.
Their findings will become part of a greater understanding of the Earth’s climate system and climate change.
Heard Island on the Kerguelen Plateau in the southern Indian Ocean consists primarily of the emergent portion of two volcanic structures. The large glacier-covered composite basaltic-to-trachytic cone of Big Ben comprises most of the island, and the smaller Mt. Dixon volcano lies at the NW tip of the island across a narrow isthmus. Little is known about the structure of Big Ben volcano because of its extensive ice cover. The historically active Mawson Peak forms the island’s 2745-m high point and lies within a 5-6 km wide caldera breached to the SW side of Big Ben. Small satellitic scoria cones are mostly located on the northern coast. Several subglacial eruptions have been reported in historical time at this isolated volcano, but observations are infrequent and additional activity may have occurred.
February 01, 2016. Mawson Peak , Heard Island , Australie :
Source : ABC, GVP.
Photos : Pete Harmsen