Chinese scientists have uncovered a crucial mechanism that explains how Earth may have stored vast quantities of water during its infancy. This discovery sheds new light on the planet's dramatic evolution from a fiery ball of magma to the life-nurturing world we know today.

Researchers from the Guangzhou Institute of Geochemistry under the Chinese Academy of Sciences have experimentally demonstrated that the planet's deep mantle could have acted as a massive reservoir for water over 4 billion years ago, according to a study published on Friday in the journal Science.

"Where did the water go when Earth's early magma oceans crystallized? For the deepest mantle, the answer has been elusive," the journal stated in an editorial summary.

The key lies in bridgmanite, the dominant mineral in the lower mantle. While it was previously believed to have a limited capacity for storing water, the Chinese team has found that this mineral actually possesses a strong, temperature-dependent ability to retain water.

They replicated the extreme conditions of the lower mantle, where high pressure and scorching temperatures reach approximately 4,100 degrees Celsius, by utilizing a sophisticated diamond anvil cell apparatus along with laser heating.

Their findings reveal a paradox: the hotter the environment, the more efficiently bridgmanite captures and stores water molecules during its formation from cooling magma.

This process could have trapped an amount of water in the solid mantle that is equivalent to between 0.08 and 1 times the volume of all modern oceans, according to the study.

This primordial water stockpile has been gradually released back to the surface through volcanic activity, playing a crucial role in the creation of a blue, habitable planet.

(Cover: An illustration of the Earth's structure. /VCG)