By using an ion probe to analyze the carbon and nitrogen isotope compositions of Witwatersrand, South African diamonds, which have been preserved for more than three billion years, researchers found that plate tectonics was likely in operation on earth as early as 3.5 billion years ago.
The location of the Witswatersrand Basin mines in South Africa is shown here:
In an article published this week, researchers at the University of Witswatersrand describe the diamonds as being like miniature time capsules recording information about the movement of the earth's tectonic plates on the earth's surface.
Lead researcher Dr. Katie Smart noted, “The nitrogen isotope composition of the Witwatersrand diamonds indicated a sedimentary source (nitrogen derived from the Earth’s surface) and this tells us that the nitrogen incorporated in the Witwatersrand diamonds did not come from the Earth’s mantle, but that it was rather transported from Earth’s surface into the upper mantle through plate tectonics. This is important because the nitrogen trapped in the Witwatersrand diamonds indicates that plate tectonics, as we recognise it today, was operating on ancient Archaean Earth, and actively transported material at Earth’s surface deep into the mantle.”
In other words, these carats are able to tell us "What's Up, Doc?" from at least 3.5 billion years ago.
Your thoughts on these carbon gems (or emeralds ;-)) and plate tectonics?
Steph
P.S. Yes, I am all set with a costume as a tardigrade for Halloween 2016:
The location of the Witswatersrand Basin mines in South Africa is shown here:
In an article published this week, researchers at the University of Witswatersrand describe the diamonds as being like miniature time capsules recording information about the movement of the earth's tectonic plates on the earth's surface.
Lead researcher Dr. Katie Smart noted, “The nitrogen isotope composition of the Witwatersrand diamonds indicated a sedimentary source (nitrogen derived from the Earth’s surface) and this tells us that the nitrogen incorporated in the Witwatersrand diamonds did not come from the Earth’s mantle, but that it was rather transported from Earth’s surface into the upper mantle through plate tectonics. This is important because the nitrogen trapped in the Witwatersrand diamonds indicates that plate tectonics, as we recognise it today, was operating on ancient Archaean Earth, and actively transported material at Earth’s surface deep into the mantle.”
In other words, these carats are able to tell us "What's Up, Doc?" from at least 3.5 billion years ago.
Your thoughts on these carbon gems (or emeralds ;-)) and plate tectonics?
Steph
P.S. Yes, I am all set with a costume as a tardigrade for Halloween 2016:
