... width of vertical earth pillar (b= const) Xn : X-axis of earth pillar no. n, xn > 0 when the earth pillar locating on the left of OY axis dSn : length of the sliding arc section locating ... weathering mainly occurs in this region. The agents of the chemical weathering mainly are water, oxide, carbonic acid, organic acid and other acids dissolved in water. The chemical weathering ... complicate features. Different processes can be happen at the same time, such as dissolution, oxidation, ion exchange and hydrolysis. The dominant of any process depends on the compositions...