## 3 Effects of the Earthquake on the Natural Environment  
The CFTI Catalogue of Strong Earthquakes in Italy [16] reports that this earthquake had two effects on the natural environment: a wide surface fracturing along Monte Corvo (M. Corvo) and a large landslide in Roccaseca (Figure 5 and Table 2). We re-positioned the fracture (number 4) that was misplaced in the Catalogue. In fact, [PERSON] et al. [16] located the fracture in Pontecorvo whilst the original source reports it at Monte del Corvo, 10 km NW of Sora. The landslide (number 7) reasonably occurred along the steep slope north of Roccasecca, where a scarf is still visible. We performed an in-depth round of investigation in local and national libraries and archives to seek new data of this type; the search in coeval chronicles, letters, and diaries and in later reports allowed us to add five new observations (Figure 5 and Table 2). Most of these new data concern hydrological changes that occurred immediately after the event. An increase in the discharge of the Gari River close to its springs in Cassino (number 1), a decreased and turbid flow of the Liri River in Isola Liri (numbers 2 and 3), and a decrease in discharge in the Fucino area (number 5) were reported. A fifth significant and previously unknown datum (number 6) derives from direct observation of fractures affecting the ancient structure of the Cathedral of Sora and it is indirectly inferred from the analysis of the church reconstruction history [17, 18]. Some of the fractures of walls and the basement are preserved and appear aligned and adjacent to the trace of the SF. Moreover, an intriguing piece of evidence regarding the Cathedral is that its northwest end (presbyterium) is presently accessed through three steps as it is higher than the rest of the building [17, 18]; however, according to the description of Bishop [PERSON] in 1618, it does not result in a higher position. This change possibly reflects a local ground deformation corresponding to the fractured zone.  
\begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline \hline
**Source** & **Langbi (Sora)** & **Width (Sora)** & **Min Depth (Sora)** & **Max Depth (Sora)** & **Stinke\({}^{\circ}\)** & **Dip\({}^{\circ}\)** & **Ratio\({}^{\circ}\)** & **Scinicic  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**No** & **Locality** & **Lat\({}^{\prime}\)** & **Lon\({}^{\prime}\)** & **Epic. dist. (km)** & **Effects** & **References** \\ \hline \hline
1 & Cassino & 41.480 & 13.832 & 21.2 &
\begin{tabular}{c} Increase in \\ discharge of Gari \\ springs \\ \end{tabular} & [19; 20] \\
2 & Isola del Liri & 41.680 & 13.574 & 10.5 & Decrease in flow \\  & & & & & from Liri River \\
3 & Isola del Liri & 41.678 & 13.571 & 10.6 & Liri River \\
4 & M. Corvo & 41.772 & 13.468 & 23.5 & Wide surface \\  & & & & & fracturing \\  & & & & & & Chams and \\
5 & Luco dei Marsi & 41.973 & 14.461 & 41.8 & lowering of waters \\  & & & & & in the Fucino Lake area \\
6 & Sora & 41.723 & 13.615 & 11.3 &
\begin{tabular}{c} Inferred coesmic \\ fracturing in the \\ flooring of the \\ Cathedral \\ \end{tabular} & [17; 18] \\
7 & Rocasecca & 41.554 & 13.669 & 9.1 & Landslide & [16; 23] \\ \hline \hline \end{tabular}
\end{table}
Table 2: List of the effects observed in the natural environment following the 1654 earthquake (progressive number corresponds to Figure 5). The epicentral distance is calculated from the location of the Italian seismic Catalogue (red star in Figure 1) [5].  
Figure 5: Distribution of the effects of the 1654 earthquake on the natural environment (see Table 1 and text for the description of the effects). Colored boxes are the modeled sources: BF, Balsorano fault; PF, Posta-Fibreno fault; SFa, Sora fault from ITHACA Working Group [12]; SFb, Sora fault from [PERSON] et al. [13]; MF, Macroseismic fault.