My OperaOldest Diamonds
Friday, August 24, 2007 9:19:41 AM
Diamonds have been found in some of Earth's oldest rocks, dating back to 4.25 billion years ago. These diamonds are a billion years older than the oldest diamonds ever found in the mines of South Africa.
Because diamonds are only formed under very high pressure this may indicate that thick crust had already formed at this early stage of the history of our approximately 4.5-billion-year-old planet, and therefore supports the idea that plate tectonics was in motion at that time. Bearing in mind that the diamonds were probably squeezed into being by the pressure of 100-150 kilometres of crustal rock lying above them.
The diamonds were found inside crystals of zircon from the Jack Hills region in Western Australia. The Jack Hills is part of the Yilgarn Craton that I reported on in my post Cratons - Australia.
The study was published on 23 August 2007 in the journal Nature.
Ian Williams, a geologist at the Australian National University in Canberra, isn't convinced of the gems' age. He bets that carbon was first inserted into zircons of different ages as pockets of graphite, which were converted to diamonds much later in history in one fell swoop.
Further research seems obviously needed.
Because diamonds are only formed under very high pressure this may indicate that thick crust had already formed at this early stage of the history of our approximately 4.5-billion-year-old planet, and therefore supports the idea that plate tectonics was in motion at that time. Bearing in mind that the diamonds were probably squeezed into being by the pressure of 100-150 kilometres of crustal rock lying above them.
The diamonds were found inside crystals of zircon from the Jack Hills region in Western Australia. The Jack Hills is part of the Yilgarn Craton that I reported on in my post Cratons - Australia.
The study was published on 23 August 2007 in the journal Nature.
Ian Williams, a geologist at the Australian National University in Canberra, isn't convinced of the gems' age. He bets that carbon was first inserted into zircons of different ages as pockets of graphite, which were converted to diamonds much later in history in one fell swoop.
Further research seems obviously needed.
- http://www.nature.com/news/2007/070820/full/070820-7.html
- http://www.physorg.com/news107079481.html
- http://www.livescience.com/environment/070822_diamonds_forever.html
- http://news.bbc.co.uk/2/hi/science/nature/6959224.stm
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