Oblique foliation

As the name implies, this foliation/fabric takes on an oblique attitude to the shear-zone boundary (i.e. the fabric attractor) and internal layering, usually an angle of about 20°–40°, or less.

A closer look reveals that the foliation/fabric is created by the parallel arrangement of a multitude of similar oriented small grains, which are slightly elongated in the foliation direction.

Occasionally mica fish get incorporated into oblique foliations; this structure has been called type II S-C-fabric by Lister & Snoke (1984).

Oblique foliations, whose angle with the fabric attractor exceeds 45°, pose a different problem difficult to reconcile with the available theory.

One possible explanation for this seemingly paradoxical arrangement may be found in transtensional shear zones transposing the ordinary oblique foliation into steeper attitudes by simultaneous extension.