Subaerial weathering of the continental rocks is an important component of global biogeochemical cycles. During the dissolution of continental rocks, atmospheric CO2 is consumed resulting in alkalinity production and its transfer to the ocean via river transport. Atmospheric carbon is also consumed during the dissolution reaction itself, as illustrated by the dissolution equation of plagioclase:

\begin{eqnarray*}&&4Na_{0.5}Ca_{0.5}Al_{1.5}Si_{2.5}O_{8}\ +\ 17H_{2}O\ +\ 6CO_{2}\ {\rightarrow}\\&&3Al_{2}Si_{2}O_{5}(OH)_{4}\ +\ 2Na^{+}\ +\ 2Ca^{2+}\ +\ 6HCO_{3}^{{-}}\ +\ 4H_{4}SiO_{4}\end{eqnarray*}

Plagioclase dissolution produces dissolved species (basic cations, bicarbonate ions, and silica) and clay minerals which can precipitate locally. Dissolution of carbonate minerals also consumes atmospheric carbon, for example:


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