The St Christophe fold

This fold structure has formed in the hanging-wall to a thrust. You can see the nature of a bedding plane here.Other bedding planes have the following orientations (strike-dip) - 038-20SE, 019-86E, 196-46W, 192-80W, 030-16SE. Use these to deduce the orientation of the fold hinge line.

What do these observations suggest as the folding mechanism here?

This anticline is one of the Jura folds that converges southwards into the Chartreuse area.  Here we see the forelimb of the fold in a quarry.

The bedding planes have striations on them. This bedding surface is oriented 192-80W, with striations pitching 80 degrees N. Relate this to the fold hinge line.