When a voyage of 40 scientists headed to sub-Antarctic territories earlier this month, they were on the lookout for underwater volcanoes, iron and the life that lies within the southern ocean.

Around 20 days in to the eight-week voyage, researchers on the RV Investigator have made some early and exciting discoveries around the Heard and McDonald islands, 4000 kilometres south-west of Perth and 2000 kilometres north of Australia's base at Davis Station in Antarctica.

"Abundant with life:" Penguins on Heard Island. Credit:Matt Curnock

"We've tentatively identified over 50 hydrothermal vent systems on the sea floor, [which are] areas where hot hydrothermal fluids that are actually cooling hot volcanic rock beneath the sea," said Professor Mike Coffin, from the Institute for Marine and Antarctic Studies, who is chief scientist of the voyage.

Speaking from on board the RV Investigator, Professor Coffin said his team is yet to see underwater volcanoes, because the water is "extremely turbid," and it is still early days, but he added that the fluids they have observed have big implications.



"Those fluids, because they are so hot, they pick up iron and other rare earth trace metals from the rocks and then they expel them into the ocean. Our hypothesis and overarching purpose of the voyage is to see if this solid earth-provided iron is actually nourishing phytoplankton up on the sea surface."