The folds in the North Yellow Sea basin are mainly classified into four origin types, namely extensional folds, compressional folds, gravitational force folds and thermogene folds.

• 其中，与张性正断层相关的伸展型褶皱分布范围最广，可进一步划分为牵引褶皱、逆牵引褶皱、滚动褶皱、翘倾褶皱、补偿性挤压背斜和断层-位移褶皱；