## 5 Palaeoseismic Trenching along the Doroud Fault
Historical and instrumental data for earthquakes with magnitude more than MW \(>\) 5.5.  
result of the normal component of the F2 fault (Figure 14c (post-event) and d (pre-event)); therefore, the deposits of wedge C1 are the result of the erosion and sedimentation of a mixture of units 4 and 16-a indicating the earthquake occurrence before the deposited unit C1 and after unit 4 (Figure 15c,d). We evaluated the maximum wedge thickness of 21.74 cm, which shows a vertical displacement of 19.43 cm at the top of unit 4 (Table 3). The event horizon of this event is the base of the C1 unit. This event occurred after the deposition of unit 4, which is a colluvial wedge sample DT1-C6, dated 2385 \(\pm\) 35 Cal BP. Hence, it postdates 2385 \(\pm\) 35 Cal BP (Figure 10). The seventh event is identified with faults F1, F2, F3, and F4 in Log fault zone B; the faults affect units younger than unit 4. These faults are younger than 3235 \(\pm\) 25 Cal BP, which is the age obtained for sample DT1-C5 collected in unit 4 (Figure 14e (post-event) and f (pre-event)). This event occurred after the deposition of unit 4; hence, it postdates 3235 \(\pm\) 25 Cal BP (Figure 10). Several distinct abruptly terminating upward fault strands, with the most demonstrative ones observed between 18 and 20 m, provide evidence for event Ev7 (Figure 16a,b). The faults F1, F2, F3, and F4 cut through unit 4 and abruptly terminate at the base of unit 16-a. Unit 4 is associated with average vertical displacements along the faults F1, F2, F3, and F4 with a range of 100 \(\pm\) 4 cm (Table 3). The event horizon has therefore been set at the base of unit 4. The calculated moment magnitude is Mw \(\sim\)7.2 (according to [51]) (Tables 4 and 5), and other calculated seismic parameters are given in Table 4.  
The eighth event is evidence of faults abruptly terminating upward and cutting units along the faults in Log fault zone B. This event was found only in the southwestern part of zone B and well-characterized by the abruptly terminating upward fault F11 at the base of units 3 and F10, cutting through the lower units 3, 2, and 1 (Figure 14g (post-event) and h (pre-event)). Unit 3 is associated with vertical displacements along the F10 that are about 60 \(\pm\) 3 cm (at the base of unit 3) (Table 3). Therefore, the event horizon of the seven paleoearthquakes is set at the base of unit 3 (Figure 16c,d). This event occurred after the deposition of unit 3; hence, it was younger than 8375 \(\pm\) 35 Cal BP, which is the age obtained for sample DT1-C20 collected in unit 3 (Figure 10). Using the fault plane parameters (Table 3) and the same equation linking them to the earthquake magnitude obtains Mw \(\sim\)7, according to [51] (Table 4), and other calculated seismic parameters are given in Table 4.  
The ninth event is indicated by unit 2 being offset by faulting in Log fault zone B. This event can be interpreted as a fault termination, with the fault F5 cutting through unit 2 and faults F6, F7, and F8 abruptly terminating upward at the base of unit 2. This event is associated with vertical displacements in unit 2 along the F5, which was calculated to be an average of 50 \(\pm\) 0.1 cm (at the bottom of unit 2) (Table 3) (Figure 14i (post-event) and Figure 14j (pre-event)). Therefore, the event horizon is set at the base of unit 2 (Figure 15c,d). This event occurred after the deposition of unit 2. Hence, it is younger than 66.62 \(\pm\) 5 ka, which is the age obtained for sample Dt1 IRSL 2 collected in the middle of unit 2 (Table 2). Using the fault plane parameter Tables 4 and 5 and the same equation linking them to the earthquake magnitude obtains Mw\(\sim\)6.8 (according to [51]) (Table 3). Figure 16: The evidence for the Ev6 event (**a,b**) and the Ev8 and Ev9 events from the fault zone B (**c,d**).