Page 91 - Microtectonics

4.2 · Foliations 79

Fig. 4.12. Differentiated crenulation cleavage in phyllite with symmetric microfolds: the foliation is defined by cleavage domains (flanks of
microfolds) and microlithons (fold hinge areas). Note the difference in composition of the two domains and the gradual transition between
both. Cordillera Real, Ecuador. Width of view 4 mm. PPL

Fig. 4.13. Zonal crenulation cleavage with a percentage of cleavage domains variable from about 25% in the lower left part to almost 50% in
the upper right part of the photograph; note the gradual transition between cleavage domains and microlithons, and the asymmetric
character of microfolds resulting in relative mica enrichment predominantly in one of two alternating fold limbs (cf. Fig. 4.12, where both
limbs are identical). Leiden Collection. Width of view 4 mm. PPL