## 3 Results
### Study Area 2--Prate Pala Fault (PTP)  
Topographic Analysis of PTP  
Despite the small offset associated with the 30 Octoberoseismic rupture, the reactivation of the PTP has highlighted soon after the mainshock thanks to the displacement of the paved road (S.P.477) from Forca di Presta to Castelluccio di Norcia (Figure 3g,h). A maximum offset of 14 cm was measured in the field in the central part of the coseismic rupture (Figure 3f), whose total length was estimated in \(\sim\)1.3 km, our data are well comparable with the results obtained in [PERSON] & Sapia 2017 [44]. The performed drone-aided mapping, which allowed the detection of tectonic scarps displacing the flat topography of the Castelluccio di Norcia plain, led to reconstruct a 3 cm resolution Digital Surface Model (DSM). DSM models elaborated using this technique also allow removal of vegetation noise. Fortunately, in the studied cases, this problem was negligible because the periods in which the aerial images were acquired (beginning of November 2016 and afterward in 2018), were preceded by several months of intense grazing with poor grass regrowth, due to deficient rainfall. Further processing of the DSM allowed to explore and analyze through the functions of the ArcGIS tools, the slope analysis, the shaded relief, and the aspect of the fault scarp. A set of 27 topographic profiles, perpendicular to the fault scarp, were drawn to investigate the morpho-structural expression of the PTP (Figure 10) and to reconstruct the along-fault coseismic slip profiles, from north to south. The systematical counter-slope (i.e., dipping towards east, thus opposite to the fault dip) topography observed west of the PTP trace is interesting, suggesting a back tilting of the hanging wall block, which is coherent with the normal kinematic of the fault. This observation, confirmed by the persistence of a long-term topographic scarp resistant to the intense breeding and plowing practiced in the area, provides further evidence of the present activity of the PTP. \begin{table}
\begin{tabular}{l l c c c c} \hline \hline  & & \multicolumn{3}{c}{**Colli Alti e Bassi Fault—CAB**} \\ \hline \multicolumn{5}{c}{**FAULT ATTITUDE**} \\ \hline \multirow{3}{*}{INSTRUMENTS} & DIP AZIMUTH & \multirow{3}{*}{DIP ANGLE} & STRIAE & MEAN RESULTANT & \multirow{3}{*}{STRIAE} \\  & Min-Max value & & TEND & PLANE & \\  & Min-Max value & & ORIENTATION & \\ \hline Hand Compass & N220-N260 & 66–72 & N180-N240 & N237/68\({}^{\circ}\) & N204 \\ Fieldmove App & N220-N260 & 67–73 & N180-N240 & N235/70\({}^{\circ}\) & N206 \\ Drone Survey & N220-N240 & 66–74 & N180-N220 & N233/70\({}^{\circ}\) & N207 \\ \hline \end{tabular}
\end{table} 
Table 1: Summary table of the data collected with the different instruments (Compass, Fieldmove, Aero-Photogrammetric survey). A comparison between the along-strike DSM-derived topographic offset and the coseismic slip profile is shown in Figure 11.  
In the first case (Figure 11a), from the northern edge of PTP, the profile increases with a medium-high slope reaching the maximum height where the topographic scarp is \(\sim\)2.3 m. Moving south, the scarp shows a gradual decrease to zero at the southernmost surface tip of the PTP. The observed asymmetric trend of the topographic offset suggests, according to [PERSON] [45] and [PERSON] et al. [46], that, during previous events, surface ground rupture propagated mainly from north to south. On the contrary, in Figure 11b, the trend of the coseismic slips shows an opposite triangular shape compared to the previous one, culminating at a maximum value of 14 cm (Figure 3f). The aforesaid works [45, 46], investigating the distribution of the slip along with the fault segments during the coseismic rupture, interpreted the triangular shape, characterizing both the profiles as due to the dynamics of rupture propagation. In particular, [PERSON] et al.