The two scientists said Alfred Wegener was correct. The continents do move as new material from the center of the Earth rises, hardens and pushes older pieces of the Earth away from each other.
They called their theory sea floor spreading. The theory explains that as the sea floor spreads, the tectonic plates are pushed and pulled in different directions.
New research also supports Mr. Wegener ideas. Scientists in Britain recently reported that large amounts of water may be trapped under the ocean plates near northern Japan. Their findings were published in the journal Geology.
A strong earthquake hit Japan in March of 2011. The quake and resulting tsunami waves killed almost 16,000 people. A team of researchers from the University of Liverpool studied the tectonic plates in the area where the earthquake took place. Their report says that when two plates meet, one may bend and end up underneath the other. During this process, it says, ocean water gets trapped below the plates and goes down past the Earth crust to its mantle.
The researchers said a large hole lies near the fault lines in Japan. They said the hole could be as much as 150 kilometers deep. Water gets carried down the hole. The report says there could be 3?times more water in the Earth mantle than there is in all the oceans.
The idea of plate tectonics explains both volcanoes and earthquakes. Many of the world volcanoes are found at the edges of plates. The large number of volcanoes around the Pacific plate has earned this area the name ing of Fire.
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