If you don't know or remember what a fault propagation fold is, it's a thrust-related fold where part of the displacement on the fault goes into faulting new rock ahead of the fault tip, and part of the displacement goes into folding, or bending the layers above the thrust.
In the 3D image below, click through the annotations to see how the thrust has propagated up-section. There are several other fault related folds in the view. Can you find them? Try clicking the full screen button on the bottom right for the full view.
(This will work best in Chrome or Firefox, but possibly not as well in Internet Explorer).
Suppe, J., Medwedeff, D. A., 1990. Geometry and kinematics of fault‐propagation folding. Eclogae Geologicae Helvetiae 83, 409–454.