在软硬相间的层状岩石中，由于抗风化能力的不同，易遭风化的岩石风化速度快，形成凹凸不平的槽穴，抗风化能力强的岩石凸出在外。In the stratified rock consisting of softer layers and harder layers, because of different weathering resistance, the softer layers are weathered more easily and quickly, forming a uneven groove, while harder layers protrudes from the surface.