A reserve of diamonds older than the Moon was discovered by an international team of scientists near the Earth’s core at a depth of more than 410km.
Diamonds that have been dormant for 4.5 billion years at a depth of hundreds of kilometers were pushed to the surface by a powerful volcanic eruption in Brazil, according to research published August 16 in the journal Science. The team led by Dr Suzette Timmerman of the Australian National University measured helium isotopes in diamonds to determine the location of ancient diamond deposits .
The team looked at helium isotopes in ultra-deep diamonds. (Photo: Independent).
The team says diamonds act as “the perfect time capsule” to help them delve deeper into the tumultuous period after the Earth’s formation. During this period, the geological activity was so intense that almost nothing of the young planet’s original structure remained.
However, researchers still suspect there is a relatively quiet area in the mantle between the Earth’s crust and core. Previously, they found no evidence to support the speculation. The first clues appeared in the 1980s when scientists noticed that some basaltic lava samples in several locations had higher-than-normal ratios of helium-3 and helium-4 isotopes . What is particularly interesting is that this ratio is similar to the isotope ratio in the first meteorites to hit Earth.
This similarity indicates that the lava coming from the depths of the Earth has not changed for billions of years. “The problem is that although basalt rocks are brought to the surface, we only have a glimpse of their history. We don’t know much about the mantle, where they form,” said Dr. Timmerman.
Dr. Timmerman and his colleagues studied the ratio of helium isotopes in diamonds born 150-230km below the Earth’s crust. “Diamonds are the hardest and most indestructible natural material known to man. They are the perfect time capsule for our exploration of the Earth’s interior. We separate helium from 23 super diamonds. deep in the Juina region, Brazil. These diamonds have the same isotope ratio as we predicted from the ancient repository, confirming that the gases collected are vestiges from the period before the Moon collided with the Earth ” . Dr. Timmerman said.