The oceans formed within a few hundred million years after the birth of the Earth. The ocean floor was covered with basaltic (CaSiO3), which gradually dissolved to provide Ca2+ to the seawater. Carbon dioxide absorbed into the ocean from the atmosphere reacts with Ca2+ and is accumulated as calcium carbonate particles. This reaction is summarized below.

CaSiO3 + 2CO2 + H2O  → CaCO3 + CO2 + H2O + SiO2


(From the birth of the earth to the time when there were no continents)

最後修改: 2023年 08月 7日(週一) 18:20