Earth's layer - mantle - ..?? (science10)?

Question

the upper mantle has a tar like consistency that allows it to flow. If the upper mantle did not have this characteristic, would there be any noticeable effects?

please explain ur answer... and THNX!!

Answer 1

Plate tectonics wouldn't exist.

Answer 2

The tar-like consistency is what allows the continents to drift on the upper mantle.  If the upper mantle did not have this characteristic, there would be no continental drift so we wouldn't have separate continents.  All the continents would still be united as one supercontinent called Rodina because they would never have broken up.  Also, if there wasn't continental drift, there wouldn't be volcanoes, earthquakes, mountains, fault lines, and any other products of plate tectonics.