Did you know that we might be able to trace human life back to the reservoirs of oxygen-rich iron between the Earth's core and mantle?
A recent research suggests that breakup of supercontinents, drastic changes in Earth's atmospheric makeup, and the creation of life might have happened due to action of plate tectonics that led to water-containing minerals seep down deep enough to meet the Earth's iron core.
This would have led to extreme conditions causing the iron to grab oxygen atoms from the water molecules and setting the hydrogen atoms free to the surface and the trapped oxygen in crystalline iron dioxide can only exist under such intense pressures and temperatures.
In order to study this, the researchers used theoretical calculations as well as laboratory experiments to recreate the environment of the core-mantle boundary.
Lead researcher Ho-kwang Mao said, "Based on our knowledge of the chemical makeup of the slabs that are drawn into the Earth's deep interior by plate tectonics, we think 300 million tons of water could be carried down to meet iron in the core and generate massive iron dioxide rocks each year".
These extremely oxygen-rich solid rocks may accumulate steadily year-by-year above the core, growing into gigantic, continent-like sizes. A geological event that heated up these iron dioxide rocks could cause a massive eruption, suddenly releasing a great deal of oxygen to the surface.
This Great Oxygenation Event, occurred about 2.5 billion years ago and created our oxygen-rich atmosphere that kick started the rise of oxygen-dependent life as we know it.
"This newly discovered high-temperature and intense-pressure water-splitting reaction affects geochemistry from the deep interior to the atmosphere. Many previous theories need to be re-examined now," Mao added.
This research was conducted by scientists from Carnegie, Stanford University, the Center for High Pressure Science and Technology Advanced Research in China, and the University of Chicago. The results were first published in National Science Review.