Scientists discover giant blobs deep inside Earth are 'evolving by themselves' — and we may finally know where they come from

Cross section of the varying layers of the earth.

We finally know where two giant blobs in Earth's middle layer came from — and they're a mismatched pair.

These strange regions in Earth's mantle, known as "large low velocity provinces" (LLVPs), are actually chunks of Earth's crust that have sunk into the mantle over the past billion years, new research suggests.