## 2 Methodology
These sources contain direct or indirect information for primary and secondary environmental effects induced by the August 1953 earthquakes in the area of the southern Ionian Islands. All these sources have been reviewed with emphasis on the primary (surface faulting and permanent surface deformation) and secondary effects (ground cracks, slope failures, liquefaction phenomena, anomalous sea waves/tsunami, hydrological anomalies, effects on vegetation, jumping stones and dust clouds) induced by the 9, 11 and 12 August 1953 earthquakes in the southern Ionian Islands, which suffered most from it. Based on the description of the earthquakes' impact on the natural environment, qualitative and quantitative information of these effects were extracted. The recorded information was classified into primary and secondary earthquake environmental effects based on the classification proposed by [PERSON] et al. [30] in the Environmental Seismic Intensity (ESI 2007) scale. Primary earthquake environmental effects are directly linked to the earthquake energy and, in particular, to the surface expression of the seismogenic source, comprisingoseismic ruptures and permanent coseismic surface deformation, including uplift and subsidence [30]. Secondary earthquake environmental effects are any phenomena induced by the ground shaking and are classified into eight main categories: (1) hydrological anomalies, (2) anomalous waves/tsunamis, (3) ground cracks, (4) slope movements, (5) trees shaking, (6) liquefactions, (7) dust clouds and (8) jumping stones [30]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Archives** & **Newspapers** & **Studied Period** & **Available Dates** \\  & & & **in August 1953** \\ \hline \multirow{4}{*}{The Press Museum of the Peloponnese—Epirus—Ionian Islands Daily Newspaper Editors Association} & ETHNIKOS KIRIX & 10–24 August 1953 & 10, 17, 24 \\  & IIMERA & 11–29 August 1953 & 11–16, 18–23, 25–29 \\  & NEOLOS CAPTROM & 11–29 August 1953 & 11–16, 18–23, 25–29 \\  & PELOPONNISOS & 11–29 August 1953 & 11–16, 18–23, 25–29 \\ \hline \multirow{4}{*}{The Vikelaia Municipal Library} & IDRASIS & 9–19 August 1953 & 9, 11–15, 18–19 \\  & I DRISOS & 9–23 August 1953 & 9, 15, 23 \\  & I IDL & 11–19 August 1953 & 11–15, 18–19 \\  & MSEOLERS & 9–19 August 1953 & 9, 11–15, 18–19 \\  & PATHS & 11–19 August 1953 & 11–15, 18–19 \\  & PROFRIGKOKS KOSMOS & 9–23 August 1953 & 9, 15, 23 \\ \hline \multirow{4}{*}{The Digital Historical Archive of the Lambrakis Press Group} & TO VIMA & 10–25 August 1953 & 11–25 \\  & TA NEA & 10–25 August 1953 & 10–25 \\ \hline \multirow{4}{*}{The Digital Library of Newspapers and Magazines of the National Library of Greece} & ELEFTHERIA & 11–28 August 1953 & 11–16, 18–23, 25–28 \\  & EMPROS & 11–23 August 1953 & 11–16, 18–23, 25–28 \\ \cline{1-1}  & The Digital Library of the Greek Parliament & TAXYDROMOS & 12–31 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Newspapers of local and national circulation used in this study for revisiting the 1953 Ionian Sea earthquake sequence and its primary and secondary environmental effects. It is important to mention that contemporary sources, such as national and local newspapers, as well as the report of IGUR [20], from which information about the earthquake environmental effects were extracted, did not include data on primary effects. The permanent coseismic uplift, which occurred mainly in the eastern part of Cephalonia, was not detected by the local population, as it neither had any immediate impact on buildings and infrastructure of the island, nor directly caused fatalities or injuries. In local newspapers, which were studied in the frame of this research and were circulated far from the earthquake-affected area, such as the newspapers of the Vikelaia Municipal Library circulated mainly in Crete, it was found that there is lack of information related to the primary and secondary environmental effects induced by the studied August 1953 events.