Chevron (geology)

Chevron folding preferentially occurs when the bedding regularly alternates between contrasting competences.

[1] Turbidites, characterized by alternating high-competence sandstones and low-competence shales, provide the typical geological setting for chevron folds to occur.

[2] In response to compressional stress, geological beds fold in order to minimize dissipation of energy.

To accommodate such constraints while maintaining sinusoidal geometry, less competent layers would need to be subjected to extensive flow.

Kinked, yielding and highly localized hinges with straight limbs greatly reduce the geometrical need for deformation.

A 1:10 ratio between the thickness of competent beds and the length appears to be the threshold required for the formation of chevron folds.