Fractures can form as a result of folding - from local stresses/strains, not the far field stresses that caused folding. Note that present day dip and curvature do not necessarily mean a higher fracture density as it the geometry of the structure at the time of fracturing that is important.
The Stearns model (Figure 1) is useful in explaining the distribution of fractures that form as a result of this bending of layers. I've used it quite a lot, to guide the population of fractures in a model in anticlinal reservoirs. Types 1 and 2 are the most predictable,
Type 1 fractures compress the beds (blue arrow in Figure 1 lower) and result from bending in the strike section of the fold.
Type 2 fractures will extend the same bed (yellow arrow in Figure 1 lower) and occur where local extension is greatest. These are often the steep hinge areas which are areas of greatest rate of change of dip - see blog "natural fracture drivers" for example of this in a Middle East anticline (Wennberg et al. 2006).
Type 3 fractures result from bending in a cross-section. This is the "text book" neutral surface that is often drawn in the cross section of a fold - type 3a forming above it in the extension part - I guess that crestal collapse fractures and faults are part of the category. Type 3b form below the neutral surface in the compressive part of the beam.
Figure 1. Fractures as a result of folding on the teton anticline, wyoming (Stearns & Friedman, 1972). Lower shows extension (yellow) and compressive (blue) movements related to type 2 and type 1 fractures respectively.
Figure 2 shows a limb of an anticline (probably detaching on salt) and the clear triangular structures could be intersecting shear fractures. Perhaps type 1 ? The triangles look like the base of a clothes iron, so I think they are called flatirons in various places, although they may be the result of other (geomorphological) processes. It would be worthwhile checking out if these structures have slickenlines to see if they are true conjugate shear or not.
Figure 2. The triangular structures on the flank of an anticline (Sierra Madre Fold Belt, Mexico) may be bounded by shear fractures.
References
Stearns D.W. & Friedman, M. 1972. Reservoirs in fractured rock. In: Stratigraphic oil & gas fields – classification, exploration methods and case histories. R.E. Kring (ed). AAPG Memoir, 16, 82-106.
Wennberg, O.P, Svånå, T,M. Azizzadeh, M, Aqrawi, A.M.M, Brockbank, P, Lyslo, K.B and S. Ogilvie, S. 2006. Fracture Intensity vs. mechanical stratigraphy in platform top carbonates: the Aquitanian of the Asmari Formation, Khaviz Anticline, Zagros, SW Iran. Petroleum Geoscience. Vol. 12, 235–245.