Tags: Ocean, earth, science. 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..f 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. © 2015 Design & Trend All rights reserved. Do not reproduce without permission.