褶皱是岩层因受力发生的一系列波状弯曲变形，是岩石中原来近于平直的面变成了曲面的表现。褶皱的形成就像用双手从两边向中央挤一张平铺着的纸而发生向上的隆起或向下的弯曲，是一种常见的地质构造，此处褶皱向下弯曲，局部褶断出现断层。 A fold is a series of undulating bending deformation in stratums due stress, causing the formerly smooth surface of the rock to hook face. This fold is bent downwards containing fault.