ABSTRACT
There is decarbonatation at the base of the soil (E2 horizon). The calcium carbonate released is partly removed in soluble form. But part is immediately reprecipitated below in a Cca horizon that is temporarily enriched in calcium before being itself caught up by the decarbonatation front. After decarbonatation, argillization of igneous rocks occurs. This provides fine material (clay and bound iron) in a very porous system.
