Scientists discover geological event that causes Earth's crust to spew 'fountains of diamonds'

There's a reason diamonds are some of our most prized possessions.

The way they're formed is truly extraordinary - deep beneath the Earth's surface, the extreme pressure and temperature gives the perfect environment for diamonds to form.

And exciting research has discovered the driving force behind diamonds exploding from the Earth's surface.

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The findings were led by the University of Southampton and published in the journal Nature. They could help shape the future of diamond exploration, revealing where the precious stones are most likely to be found.

First, a bit of background - there's a reason diamonds are so coveted. They're millions or billions of years old, and are normally found in a type of volcanic rock called kimberlite.

We've been mining diamonds for centuries, but we've never quite known how they got to the Earth's surface.

That's what this research has solved, after looking at the effects of global tectonic forces on volcanic eruptions over the last billion years.

Lead author of the study Dr Tom Gernon, associate professor of Earth science and principal research fellow at the University of Southampton, said: “The pattern of diamond eruptions is cyclical, mimicking the rhythm of the supercontinents, which assemble and break up in a repeated pattern over time. But previously we didn’t know what process causes diamonds to suddenly erupt, having spent millions – or billions – of years stashed away 150 kilometers beneath the Earth’s surface.”

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The research discovered that most kimberlite volcanoes erupted 20 to 30 million years after the tectonic breakup of the Earth's continents.

“We found that a domino effect can explain how continental breakup leads to formation of kimberlite magma. During rifting, a small patch of the continental root is disrupted and sinks into the mantle below, triggering a chain of similar flow patterns beneath the nearby continent,” said study co-author Dr Stephen Jones, associate professor in Earth systems at the University of Birmingham.

The researchers were able to model the migration rates of rock - and deduce when past volcanic eruptions might have happened. All this means they're able to scientifically guess where diamonds might be deposited.

And it could have a bigger impact than just getting more sparkles into your jewelry box.

Gernon said: “Breakup not only reorganises the mantle, but may also profoundly impact Earth's surface environment and climate, so diamonds might be just a part of the story."