Huge Ocean of Water Discovered Deep Below Earth's Surface
A massive reservoir with three times the volume of all of the oceans combined has been discovered deep below the Earth's surface. This finding could give credence to the belief that the oceans came from within.
According to News Scientist, "The water is hidden inside a blue rock called ringwoodite that lies 700 kilometres underground in the mantle, the layer of hot rock between Earth's surface and its core."
In the past, geologists believed that water may have arrived on comets, but this finding suggest that the oceans could have gradually oozed out of the interior of early Earth, Science Codex reported.
"It's good evidence the Earth's water came from within," says Steven Jacobsen of Northwestern University in Evanston, Illinois. Jacobsen also stated that the interior ocean could act as a buffer, keeping the 4 oceans on the surface at relatively the same size for millions of years.
For their study, Jacobsen's team used 2000 seismometers to study the seismic waves generated by more than 500 earthquakes. The waves move throughout Earth's interior, including its core, and can be felt at the surface.
"They make the Earth ring like a bell for days afterwards," Jacobsen said.
The researchers discovered the water by noting that the waves slowed down considerably since it takes them longer to get through wet rocks than dry rocks.
News Scientist also reported that "Jacobsen worked out in advance what would happen to the waves if water-containing ringwoodite was present. He grew ringwoodite in his lab, and exposed samples of it to massive pressures and temperatures matching those at 700 kilometres down."
Jacobsen's findings only support the idea that there is a large amount of water beneath the United States. He would like to find out if it extends around the entire planet.
"We should be grateful for this deep reservoir," said Jacobsen. "If it wasn't there, it would be on the surface of the Earth, and mountain tops would be the only land poking out."
The findings on the massive ocean beneath Earth's surface were published in the journal Science.