Two simple kinematic models of folding in tectonites have been adopted and diagrams prepared to show ideal geometrical transformations of a set of parallel surfaces (S) as a result of superposition of one generation of folds on another.

It was found for both models of folding that a second generation does not necessarily form folds with constant trend and plunge. These folds depend for their axial orientation on the attitude of S in which they form. It was found also that cylindroidal folds of a second generation are necessarily smaller and less persistent in axial direction than those of an earlier generation.

Geometry of rotation of early formed B lineations by later folding is different for the two models of folding adopted. Where the second folding is by flexural slip of S, the earlier lineations follow small-circle paths in projection, as described by Sander. Where S is slip-folded by the second deformation, earlier lineations ideally follow great-circle paths in projection. Some departures from this ideal geometry to be expected in nature are listed.

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