In short:
A deep-drilling exploration of an ancient basin has uncovered fossilised corals, trilobites and unseen rock combinations.
asserted
exploration → drill → corals
Scientists will use samples to determine how ancient Devonian-era fish grew so big.
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fish → use → samples
The fossils will help scientists understand the seabed's history, but geologists did not find a salt layer they were looking for.
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they → help → layer
For millions of years, outback Queensland has hidden an ancient coral reef deep beneath its surface.
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Queensland → hide → surface
Scientists hope the discovery of ammonite, coral and fern fossils, as well as a kilometre-long solid rock core, could help unravel marine mysteries dating back more than 325 million years.
uncertain
discovery → hope → years
Geologists from Geoscience Australia found the specimens after drilling a 3-kilometre-deep hole in western Queensland to collect hundreds of rock and groundwater samples from the ancient Adavale Basin.
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Geologists → find → Basin
Experts say the fossils offer insight into life in the Devonian era, when the world was warmer, sea levels were higher and the reef now buried beneath outback Queensland teemed with marine life.
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reef → say → life
"Often we hear about things that are found at the surface," said Espen Knutsen, a senior curator from the Queensland Museum.
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Knutsen → hear → Museum
"But they might forget about all the stuff that's still hundreds of metres underground.
uncertain
that → forget → metres
"
Reef fossils extracted, but no salt
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fossils → extract → ?
Geoscience Australia drilled to a depth three times the height of the world's tallest skyscraper as part of a $30.9 million project about 63 kilometres south-east of Blackall in western Queensland.
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Australia → drill → Queensland
It was meant to find eastern Australia's only known rock salt deposit, the Boree Salt layer, which geologists had hoped could be turned into an underground hydrogen battery.
uncertain
geologists → mean → battery
But Geoscience Australia's Mitchell Bouma said the deposit was not there — at least not in form.
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deposit → say → form
Instead, the agency found fossilised corals, sea sponges, ammonites and trilobites, providing fresh evidence of a "relatively rich reef ecosystem" buried underneath Australia.
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agency → find → Australia
"We did not find any salt, but we did intercept other types of evaporative rocks, [which] are formed by the evaporation of a highly saline lake or cut-off ocean," Mr Bouma said.
"
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Bouma → find → lake
What this really means is that the halite rock salt was there but was dissolved from this location somewhere around 325 to 370 million years ago.
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salt → mean → location
"
Unravelling the secrets of giant fish
Some of the specimens have attracted international attention, including rocks that could help explain why prehistoric fish grew so big.
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fish → unravel → rocks
Geologist Geoffrey Gilleaudeau from George Mason University in the United States visited Australia in July to inspect some of the limestone samples.
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Gilleaudeau → visit → samples
He said larger fish and animals needed more oxygen, and he wanted to investigate whether the Adavale Basin fossils were evidence of a major rise in ocean oxygen levels, as previously detected in North America.
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fossils → say → America
"We're trying to see if that's a global signal, and that's why we're looking at another place which is very, very far away in the Adavale Basin in Queensland," Dr Gilleaudeau said.
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Gilleaudeau → try → Queensland
Dr Knutsen said little was known about the ancient reefs buried underneath Australia.
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little → say → Australia
In 2007, a Geological Survey of Queensland report found a "rich, varied and largely undescribed" fossil record of corals, molluscs and algae in the Bury Limestone under outback Queensland.
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report → find → Queensland
Dr Knutsen said most of those fossils were only ever surfaced by mining companies or during deep-earth exploration.
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most → say → exploration
"Who knows what we might be able to find if we could really, really just sort of dig through and see what kind of fossils it preserved?" he said.
uncertain
he → know → fossils
The Aporia
