342 TECTONICS/Folding Figure (A) A folded aplite dyke cutting a dolerite body, Outer Hebrides, Scotland (B) A folded single layer, in which the folds are isoclinal No further shortening of the layer can occur by limb rotation Further compression may result in homogeneous flattening of the folds or in the folding of the layer into larger wavelength folds (see C) (C) A tapered quartz vein showing buckling on two scales On both scales, the wavelength is seen to decrease with decrease in layer thickness