## 5 Discussion
### Activity and Distribution of the Wangjiabian-Houjiawan Fault
The fault zone shows the strongest faulting activity since the Late Pleistocene in the Bailu Loess Tableland, but much weaker within the other three geomorphic units. In those geomorphic units, the fault displacements, in order from largest to smallest, are the Bailu Loess Tableland, the Tongren Loess Tableland, the Shenhe Loess Tableland and the Shaoling Loess Tableland. Topographic profiles in Figure 7b-f show that both the elevation and the relief of the fault related geomorphic units decrease gradually from northeast to southwest (see the topographic profile locations in  
Figure 7: **(a)** Vertical displacements since the Late Pleistocene along the Lintong–Chang’an Fault Zone (LCFZ). **(b)** Topographic profile along the LCFZ. **(c–f)** Topographic profiles across the LCFZ. Profile locations are shown in Figure 1c. Figure 1c). This indicates that the activity of the LCFZ since the Late Pleistocene is irrelevant to the regional topographic expression, and it demonstrates a wave-like characteristic (Figure 7a). Additionally, information regarding Late Pleistocene activity and slip rate data for other major active faults within the Weihe Graben, particularly around the Xi'an Depression, was also compiled (Table 4; Figure 1b). Among these active faults, the Northern Qinling Fault, as the southern boundary of the Xi'an Depression, is the most active one in the Weihe Graben. It is a Holocene active fault with multiple paleoearthquake events [23] and has controlled the sedimentary process of the Weihe Graben since Cenozoic [1; 9]. The average vertical displacement along the Northern Qinling Fault within the past 14,000 years is close to 7.31 m [23], and the fault mainly exhibited a left-lateral strike-slip motion since the Late Quaternary, with a slip rate about 1 mm/a [24; 25; 26; 27]. The Weihe Fault at the northern boundary of the Xi'an Depression is less active in the Holocene compared to the Northern Qinling Fault, and the average vertical displacement on the bottom boundary of the paleosol S1 is close to 20 m in the eastern segment [28]. The western tip of the fault displays a horsetail fractures feature, which may be attributed to a strike-slip motion (Figure 1b) [29; 30]. The Longxian-Qishan-Mazhao Fault on the western boundary of the Xi'an Depression is primarily characterized by a left-lateral strike-slip motion, with an average displacement around 80 m since the Late Pleistocene [31]. However, as the eastern boundary of the Depression, the activity of the LCFZ since the Late Pleistocene is much weaker. Additionally, recent studies indicated that the Kouzhen-Guanshan Fault and the Weinan Loess Tableland Fault in the Weihe Graben also experienced a left-lateral strike-slip motion since the Late Quaternary. The strike-slip rate of the Kouzhen-Guanshan Fault is around 0.49 mm/a since the Late Pleistocene [33], and the left-lateral strike-slip motion along the Weinan Loess Tableland Fault was verified by oblique striae [37]. This suggests that most active faults within the Weihe Graben displayed a certain amount of left-lateral strike-slip motion since the Late Quaternary, which infers a possible strike-slip motion along the LCFZ. Furthermore, according to the seismic reflection profiles, there may be an additional fault on the northwestern side of the LCFZ accommodating a portion of the regional faulting motion [38; 39], which might explain the relatively lower vertical slip rates along the LCFZ. Therefore, further investigations on the additional fault and the strike-slip motion of the LCFZ are needed.