FOLDS AND FOLDING

Stratified or layered rocks or the rocks containing distinct planes that make it an isotropic (material properties different in different directions when stress is applied) generally give rise to waveforms or FOLDS or BUCKLE FOLDS which are not chaotic structures but are regular waveforms with a definite periodicity when compressive stress is applied to the layered complex at any angle which is less than 45° . If the angle is greater than 45° , the structures that result do not shorten the layered complex but extend it and extensional structures are formed.