More water than all of Earth's oceans is thought to reside deep inside the mantle, and a newly-discovered gem just shed more light on the mystery.
Helium-3 released at Earth’s surface contains tales from the deep planet and the deep past.
A new study suggests that an alien world that smashed into infant Earth and created the Moon might have left vast remains inside our planet.
The subterranean remains of 100 volcanoes formed some 180 million years ago were detected under a major petroleum hotspot.
Scientists used the second largest earthquake on record to glimpse the terrain 410 miles under our planet's surface.
A new study estimates that Earth’s interior contains 1000 times more diamond than we thought.
A new type of ice found in diamonds suggests pockets of liquid water exist deep in Earth’s mantle.