Due to chmical decomposition of silicate and alu minosilicate from coastal plain,SiO_2 particle adsorbed on clay particle and carbonate particle,and they were carried into de positional basin by running water.

• 由于滨海平原上硅酸盐和铝硅酸盐的化学分解,SiO_2质点吸附在粘土质点和碳酸盐质点之上,被流水搬运进沉积盆地。