Folding occurs when layers of rock in the crust buckle due to collisions between tectonic plates. There are two main types of folds: anticlines, where the rock layers buckle upwards in an inverted U-shape, and synclines, where layers buckle downwards in a U-shape. Different kinds of folds form depending on the direction and amount of compressional forces, including symmetrical, asymmetrical, overfolded, recumbent, and overthrust folds. Folding of layers can result in the formation of fold mountains over geologic timescales.

1. Landscape Folding

8. Anticline and Syncline

14. Different folds Symmetrical fold Asymmetrical fold Overfold Recumbent fold