Australian scientists have uncovered an addition to the famous Twelve Apostles, the limestone columns in the sea off Victoria’s Great Ocean Road.
Another five extra limestone columns have been found hidden, about 6km offshore and 50 metres beneath the surface, during sonar mapping of the seafloor.
Scientists called them the Drowned Apostles.
Here are divers taking samples (GoPro footage by Timo Friedrich):
Researchers say the existence of the Drowned Apostles is remarkable. Being limestone, they should have quickly eroded and dissolved in seawater.
The discovery was made by PhD student Rhiannon Bezore, Associate Professor David Kennedy from the University of Melbourne’s School of Geography and Deakin University’s Dr Daniel Ierodiaconou.
“Sea stacks are always eroding, as we saw with the one that collapsed in 2005, so it is hugely surprising that any could be preserved at that depth of water,” Kennedy said. “They should have collapsed and eroded as the sea level rose.”
Like the Twelve Apostles, the newest additions would have once been part of larger limestone sea cliff.
Dr Ierodiaconou’s sonar data was collected using the latest advances in multi-beam sonar technology aboard Deakin’s $650,000 research vessel Yolla.
The data is part of a project to map the reef estate in Victoria which supports commercial fisheries for southern rock lobster and abalone.
The latest findings are published in the US-based Journal of Coastal Research.