Mesozoic sedimentary mudrocks in the Youjiang River Basin have undergone regional high strain deformation and very low grade metamorphism (illite crystallinity indices are 0 331° 0 265°△2θ corresponding to the anchizone).Detailed textural and chemical relationships for chlorite white mica stacks and fine grained matrix phyllosilicates have been studied using X ray diffraction (XRD),transmission electron microscopy (TEM) and electron microprobe analysis (EMPA) methods on the basis of field and optica...