**5.2 Iron and magnesium substitution in chlorite**

Iron and magnesium substitution in chlorite is shown in Fig. 7. The x-axis indicates I(003)/I(005), related to the D value, and the y-axis indicates [I(002) + I(004)]/I(003)′, related to the Y value. In this parameter space, the amount of iron in the hydroxide and silicate layers is shown by dotted lines. For host tectonic melanges, the iron content in both hydroxide and silicate layers is relatively higher than that in the cataclasite samples. The iron content in the host tectonic melanges is distributed over a wide area (Fig. 7). In contrast, these plots show that the iron in cataclasites with pseudotachylyte is concentrated in a smaller area around smaller iron content of both the hydroxide and silicate layers.

Fig. 7. A diagram of the Fe–Mg substitution of chlorite.

#### **5.3 lllite crystallinity**

The illite crystallinity of the tectonic mélange and cataclasites samples is shown in Fig. 8. The host melange samples have an illite crystallinity ranging from about 0.3 to 0.46, with an average value of about 0.4. Illite crystallinity in the cataclasites with pseudotachylyte varies from 0.41 to 0.58, averaging around 0.46. The larger values of crystallinity suggest that the illite in cataclasites is less crystallized than in the host melanges.

#### **5.4 Semi-quantification between illite and chlorite**

The semi-quantification of illite and chlorite was conducted using the MIF method, as described above. The results are shown in Fig. 8. The illite ratio to chlorite for host rocks ranges from about 20 wt% to about 70 wt%, with an average value of 46 wt%. The same ratio in cataclasites with pseudotachylyte varies from 40 wt% to 90 wt%, with an average of 65 wt% (Fig. 8). The illite to chlorite ratio is larger in cataclasites than the host melanges, suggesting that the amount of illite increases in cataclasites if the amount of chlorite is constant, or the amount of chlorite decreases relative to the amount of illite.

Fig. 8. Illite ratio to chlorite (wt%) vs. illite crystallinity for host rocks and cataclasites with pseudotachylyte
