Position of axial plane:
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Symmetrical folds: A symmetrical fold may be an anticline or syncline.
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Asymmetrical folds: These folds, anticlines or synclines in which the limbs are unequal in length and dip unequally on either side are termed asymmetrical.
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Overturned folds: These are actually folds with inclined axial plane in which both the limbs are dipping essentially in the same general direction.
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Isoclinal folds: These are groups of folds in which the limbs are dipping essentially in the same direction and at equal angles. Consequently their axial planes are essentially parallel.
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Recumbent folds: These can be treated as extreme types of overturned folds in which the axial plane acquires a horizontal attitude. In such folds one limb comes to lie vertically above the other.
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Conjugate folds: In certain cases a pair of folds that are apparently related to each other may have mutually inclined axial planes. The individual folds themselves may be anticlinal or synclinal or their modifications.
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Box fold: It may be described as a special type of folds with exceptionally flattened dip and steeply inclined limbs almost forming three sides of a rectangle.