[2] Refolded folds are complex three-dimensional structures that form during a single progressive event or by two or more folding events [Ramsay, 1967]. They are typically recognized in layered rocks by folded axial surfaces and different types of interference patterns [Ramsay, 1967].

How are recumbent folds formed?

Theoretically, there are a number of ways in which a recumbent fold might be generated: by a roller action, with the upper limb rolling over the hinge and becoming the lower; by the upper (or lower) limb behaving relatively rigidly and extending the lower (or upper) limb to give, at the limit, a thrust (see Fig.

What is a simple fold in geography?

Simple/Symmetrical fold. This type of fold has two limbs of equal steepness. It results when the two opposing forces moving towards each other are of equal strength.