Mysterious, Huge Blobs in Earth's Mantle Cause Seismic Activity - Popular Mechanics

These structures in Earth’s mantle are likely responsible for geological phenomena, like volcanic activity in Africa.

• Newly discovered blob-shaped structures are the biggest ones we’ve seen in Earth’s mantle so far.
• Located low in the mantle layer, the blobs influence the motions of the mantle and… [+3112 chars]
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