By DPA
Sydney : Diamonds almost as old as the Earth itself have been found in Australia, and a close examination of the tiny gems could prove that our planet cooled much more quickly than previously thought, scientists said Thursday.
“The results will reinvigorate questioning of the cool-Earth concept,” Australian National University palaeontologist Ian Williams said in a statement.
Williams, who was not part of the research team that found the precious remnants of the Earth’s crust in the Jack Hills region of Western Australia, said the diamonds could shed light on a period that is the geological equivalent of the Dark Ages.
“The formal name given to the period, the Hadean, matches the long-held view that during this time Earth’s entire surface, or at least large tracts of it, was a hellish, seething mass of molten lava,” he said.
The diamonds, found encased in zircon, are more than four billion years old.
The research team, led by Martina Menneken of Germany’s Munster University, estimate they could have formed only 300 million years after Earth itself was created from the dust and debris encircling the Sun around 4.5 billion years ago.
“Zircon crystals are tough and relatively resistant to being melted, thereby retaining vital clues about past events occurring in the Earth’s crust and mantle,” Williams said.
The researchers believe the diamonds are evidence of a relatively thick continental crust as early as 4.25 billion years ago.
The crystals were dated using uranium and lead isotopes and found to be more than one billion years older than the previous oldest-known diamonds.
The Jack Hills diamonds were found 2 years ago, and the findings of the German-Australian research team appear in the latest issue of the journal Nature.