There is an epoch in the Earth history termed the “Great Oxygenation Event” (GOE). I described it in my recent post on the rise of molecular oxygen in earth’s atmosphere.
The “Great Alkalinity Event” is really just another “side-effect” of the GOE, namely causing most water on this planet to become alkaline, the opposite of acidic.
As you might have guessed already, there is more chemistry involved – my favored subject. Trust me; I’ll try to keep it simple, short and to the point. If still in doubt, just confer with my dearest about that!
Oxygenation = Reduction
The increase of molecular oxygen in the atmosphere by the GOE was by way of loss of that oxygen from the then highly ubiquitous carbon dioxide (CO2). In chemical parlance, the (fully oxidized) carbon dioxide got ”reduced” to material with less than two oxygen (“O”) atoms per carbon (“C”). The notation “CO2” simply is the chemists’ short form for carbon-di(meaning two)-oxygen atoms for a compound (also termed molecule) consisting of one carbon and two oxygen atoms.
Just like in physics, where energy or mass cannot be created but only converted from one form to another, the same law of “energy/mass conservation” also demands conservation of atoms. Therefore if one substance gains any atoms, another must lose the same number and kind. In contrast to “money,” that many of the world’s central banks can create with a “mouse click” and “ex nihilo,” both chemistry and physics command adherence to a balanced mass equation.