The morphology of desert cliffs is strongly controlled by the resistance and thickness of the caprock layer at the cliff top: a thick, highly resistant caprock protects the underlying weaker strata from erosion, sustaining a tall, steep, well-defined vertical cliff face as the slope retreats; a thinner (but still resistant) caprock provides less protection, producing a somewhat less pronounced or lower cliff; and a weak (non-resistant) caprock offers little to no protective capping effect, allowing the underlying slope to degrade into a more gentle, poorly defined profile lacking a sharp cliff form.