Fig. 3
Frequency distributions of the long-axis orientations of tourmaline grains on the foliation surface in each sample (EP6fb, MB28, EP10oc, MB15, EP11fi, MB14, MB23, MB39, and MB23L). Best-fit curves, based on the von Mises distribution, are also shown (for details of the method, see Masuda et al. 1999). θ is the orientation of the tourmaline grains. N is the total number of measured tourmaline grains, κ is the concentration parameter, d 0 is the confidence interval for the critical region of 0.05 (Masuda et al. 1999), and κ u and κ l are the 95% upper and lower confidence limits, respectively. The distribution is arranged to set the mean orientation = 90°, corresponding to the mean orientation of the lineation