12Glomar ChallengerDrilling for Rocks (and used for other things! but we’d have to kill you if we told you what it was for )
13Can it Spread Forever??No Way, It has to go somewhere, and usually it dives under a continent!Oceanic Crust is Denser than Continental Crust – so it sinks under the continent.This process is called Subduction and makes the Deep Ocean Trenches
18Hawaii is SpecialHawaii is special, it is on the Pacific Plate, but the hotspot under the Big Island appears to have been there for 70+ million years.The evidence is the chain of islands stretching out to the NW from Hawaii to Kure – and on along the Emperor Seamount chain.