Scientists detect unexpected widespread structures near Earth’s core

A few years ago I posted about an “Atlas Of The Underworld” that had been produced that revealed a hundred or so former continents that had been subducted and were floating around in the mantle sloooooowly melting away. These continental slabs are dozens to hundreds and perhaps billions of years old, and are still only hundreds of kilometers deep. But now evidence has come to light of structures far deeper, down near the core-mantle boundary. These seem unlikely to be former continents that sank… I’d guess they are structural discontinuities that have been there since the Earth condensed from the original dust cloud.