fold: Quick Facts

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Facts

Also Known As	folding • tectonic fold • rock fold

Photos

Layered metamorphic rock formation with dramatic folds exposed on a roadside cliff next to a highway.

Diagram showing three types of geological folds: a syncline with a downward trough, an anticline with an upward crest, and a monocline with a single bend, all labeled with axes, limbs, and axial plane.

Diagram showing four types of geological folds in layered rock, from left to right: symmetrical fold, asymmetrical fold, overfold, and recumbent fold, with the inclination of the axial plane decreasing across the sequence. Red lines indicate the axial planes and axes, and the layers are shaded in brown tones.

Figure 20: The forms of three types of folds.

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Topics

axial plane isoclinal fold asymmetrical fold synclinorium syncline anticlinorium anticline fold axis symmetrical fold recumbent fold fault joint How are mountains formed?Nevadan orogeny Laramide orogeny Taconic orogeny Acadian orogeny Hudsonian orogeny Alleghenian orogeny Kenoran orogeny