Following up on theories that ringwoodite minerals deep within the Earth’s mantle may contain water, a BBC News report says researchers have provided the first direct evidence of this theory.
Diamonds, brought to the Earth’s surface in violent eruptions of deep volcanic rocks called kimberlites, provide a tantalising window into the deep Earth.
A research team led by Prof Graham Pearson of the University of Alberta, Canada, studied a diamond from a 100-million-year-old kimberlite found in Juina, Brazil, as part of a wider project.
They noticed that it contained a mineral, ringwoodite, that is only thought to form between 410km and 660km beneath the Earth’s surface, showing just how deep some diamonds originate.
While ringwoodite has previously been found in meteorites, this is the first time a terrestrial ringwoodite has been seen. But more extraordinarily, the researchers found that the mineral contains about 1% water.
According to the news report, this discovery is important because it solves a 25-tyear-old controversy about deep Earth being wet, dry, or wet in patches. The finding implies that the interior of the planet may store several times the water in the oceans, and demonstrates how hydrogen plays a critical role in the interior processes of the planet, and possibly other planets including Mars.
For more information on ringwoodite:
- Ringwoodite Mineral Data
- There’s a Huge Underground Ocean That Could Explain the Origin of Seas – TIME
- Hydrous mantle transition zone indicated by ringwoodite included within diamond – Nature Publishing Group
- Rare Diamond Confirms That Earth’s Mantle Holds an Ocean’s Worth of Water – Scientific American
- Water in Earth’s mantle revealed by diamond containing the mineral ringwoodite – Slate
- Ringwoodite – Wikipedia