A brand-new ocean spotted near Earth’s core 

Scientists have recently traced a massive ocean near the Earth’s core, once again proving that it is indeed the Blue Planet. In other words, the transition zone between the Earth’s upper and lower mantle (closer to the core) has been reported to contain large quantities of water. In fact, this has finally confirmed what has so long been just a theory that ocean water comes with subducting slabs (tectonic plates pushing down) and in turn enters the transition zone. Can you guess what this means? Yes, Earth’s water cycle goes down all the way to its interior.  

This latest research was carried out by a team of geologists based at Institute for Geosciences at Goethe University in Frankfurt, Germany. They further located rare diamonds 660 metres below the Earth’s surface using methods such as Raman spectroscopy and FTIR spectrometry. Are you wondering what has diamond got to do with the formation of an ocean? Well, when the diamonds undergo transformation, they obstruct the motion of rocks in the mantle. This means that hot and rising columns of rock from the inner mantle called mantle plumes, which were earlier thought to move beyond the transition zone, don’t always do so. This, in turn, makes the subducting plates weaker and breaks through the transition zone, allowing ocean water to sneak in.  

However, apart from enormous amounts of ocean water, this region also contains other geochemical substances such as deep-sea sediments, that further push into the Earth’s interior. The sediments mainly comprise of carbon dioxide, alongside stable hydrous minerals and carbonates. In fact, scientists are now concluding that such sediments, such as wadsleyite and ringwoodite too, hold immense quantities of water, almost six times the amount present in our earthly oceans. Fascinating, isn’t it?  

Interestingly, the recent study was conducted with data provided by a diamond mine in Botswana, Africa. Previously, this rare diamond’s origin was a mystery. But now, its super-deep place of origin has been detected, that also has high water content. If this wasn’t all, the exact chemical composition of this exquisite diamond was also traced and comprises of basalt found in mantle rocks.  

So, finally, the world knows that the transition zone between Earth’s mantle and core is not a dry sponge (as earlier presumed), but instead a wet and sedimented region. Moreover, it also makes the zone far more dynamic, allowing it the incentive for global material circulation.