A study of Science Advances shows that the Géodynamo and the oxygen atmospheric evolve in parallel. In fact, our planet draws as much from its bowels as from its oceans and forests to breathe.
The magnetic field and oxygen come from very different processes … but evolve together
The Earth’s magnetic field comes from convection movements in the liquid of the earth. This natural system, similar to a dynamostrengthened there is 540 million yearswhen the internal core started to solidify.
For his part, Atmospheric oxygen is produced by the photosynthesisa biological process that appeared there is 2 billion years. He sparked two major revolutions: the Large oxidation (2.4 billion years) and theexplosion cambrienne (500 million years), a period of massive expansion of life.
And yet, despite their opposite origins, a Strong correlation appeared: each reinforcement of the magnetic field coincides with an increase in the oxygen level. These synchronization phases also follow the Great climate upheavalslike some glaciations or sudden warming.
Supercontinents and tectonic plates modify the internal balances of the earth
The formation of supercontinents like the Pange Disturbed the heat transfer between the coat and the core. This has the effect of to strenghten or ofweaken Geodynamo, depending on whether heat is blocked or released.
In addition, the subduction leads to the depths of Oxygen -rich rocks. There they undergo chemical reactions complexes. These reactions can oxygen or on the contrary trap him. Thus, the Movements of the earthly crust also influence the composition of the atmosphere.
Scientists have also observed Oxygen old old areas Usingsulfur and iron isotopes. Once exposed to air, these pockets can release large quantities of oxygen with a strokecausing Sudden peaks in the atmosphere.
Life and the terrestrial nucleus are more linked than we imagined
These discoveries modify our gaze on the planet. They show that the biosphere (life) and geosphere (the interior of the earth) interact in depth.
By extension, this could explain why Mars or VenusWho do not have an active magnetic field,, never been able to retain enough oxygen to allow the emergence of life.
To deepen this track, researchers want to create coupled models. These simulations will have to integrate both the paleomagnetismthe geochemistryand the Plates tectonicsin order to Reconstitute the evolution of the atmosphere over millions of years.
The earth exchange oxygen with its depths as a living organism
What this study reveals is that Earth is not a divided systembut a global organization. What produced The heart of the planet can influence the air we breathe.
Understand this deep link between Géodynamo et oxygen could well transform our vision of life on earth … and elsewhere.