earth's mantle

The Earth's core may be hiding dozens of hydrogen oceans.
new research suggests that the earth's core contains an amount of hydrogen equivalent to 45 oceans, which could influence volcanic activity.
Fascinating facts about the Earth's mantle
the earth's mantle is the thick layer of hot, solid rock that lies between the earth's crust and the molten iron core. it makes up the bulk of the earth, accounting for two-thirds of the planet's mass.