Scientists have discovered a 650 million year old, 1 km wide reef, sitting in Australia’s outback. Fossils of ancient sponges or other early primitive animals may be awaiting discovery there, say antipodean researchers.
Jonathan Giddings, of the University of Melbourne, says the reef is of “internationally significant” because it dates from a 5-10 million year period between two major ice ages.
“It provides a significant step forward in showing the extent of climate change in Earth’s past and the evolution of ancient reef complexes – and it also contains fossils which may be of the earliest known primitive animals” says Giddings (press release).
“There is a good chance that the new fossils and organisms found in the reef will provide significant insight into the evolution of early multi-cellular life.”
Dubbed ‘Oodnaminta’, the reef was laid down not by corals but by microbial organisms, and maybe those ‘early multi-cellular’ creatures that Giddings is talking about. The reef has been turned 90 degrees skywards, exposing a 20 km stretch for researchers to pour over.
“The giveaway it is a reef is that there’s a large mass of carbonate which forms when organisms have grown together in a complex framework,” says fellow researcher Malcolm Wallace.
Local tidbits
Just 10 kilometres from a controversial uranium exploration site in South Australia’s Flinders Ranges, geologists have unearthed tantalising evidence of the earliest complex life on Earth.
“It’s ironic that we’ve made this 650-million-year-old discovery down the road from where Marathon Resources was caught dumping unauthorised waste in Arkaroola Wilderness Sanctuary, but it won’t put our work at risk,” said team leader Malcolm Wallace with the University of Melbourne School of Earth Sciences.
The team first visited the remote reef site in 2004, intrigued by satellite images, aerial photographs and old geological maps which suggested an interesting structure could be found.