The chemical weathering of rock-forming minerals like silica over long periods of time –that is, thousands of years – leads to the formation of clay soils. As parent materials break down into smaller particles through the weathering process, they combine with decaying organic material to become soils.

像二氧化矽這樣的造岩礦物在很長一段時間內（即數千年）的化學風化作用導致了粘土的形成。 隨著母質通過風化過程分解成更小的顆粒，它們與腐爛的有機物質結合成為土壤。

節錄自https://sciencing.com/how-is-clay-soil-formed-13406937.html