短語詞組短語ripple -mark wave length 波痕波長superimposed ripple -mark 迭加波痕ripple mark -like structure 波痕狀構(gòu)造hexagonal cross -ripple mark 六方交錯波痕flat -topped ripple mark 平頂波痕mud -ridge ripple mark 泥嶺漣痕 返回 ripple mark