## 7 Secondary Environmental Effects Induced by the 1953 Ionian Sea Earthquakes
### Secondary Effects Induced by the 12 August 1953 Ionian Sea Earthquake in Cephalonia Island
#### 7.3.1 Slope Failures
Pyrgi village, founded on the eastern slopes of Roudi Mt located between Ayia Dynati Mt in the north and Aenos Mt in the south, was also affected by rockfalls (Figure 11; TAXYDROMOS, 19.08.1953). The boulders were accumulated on the adjacent roads resulting in temporary traffic disruption. West of Roudi Mt, Valsamata village suffered from slope failures (Figure 11). Rockfalls were generated along the slopes over the village and contributed to its complete destruction, which was already heavily affected by the earthquake ground motion (TAXYDROMOS, 14.08.1953). Monastirak and Tzanata villages, founded in the southern slopes of Atros Mt in the eastern part of Cephalonia, were also affected by slope failures (Figure 11). Rockfalls were triggered along an abrupt slope northeast of Monastirak [20]. In Tzanata, rockfalls were triggered along the slopes over the village. Boulders detached from the bedrock, rolled down towards the village and caused heavy structural damage to buildings (TAXYDROMOS, 14.08.1953; I MERA, 14.08.1953). As a result, they increased the number of fatalities and injuries in the area. The southern and southeastern front of Aenos Mt (Figure 10c,d and Figure 11) was severely affected by slope failures induced by the 12 August 1953 earthquake [20]. Extensive rockfalls were generated. Atsoupades, Kolaitis, Arginia, Chionata and Platees villages (Figure 11) suffered damage, while the roads in the area were blocked (I MERA, 13.08.53). In Atsoupades village, boulders detached from the abrupt slopes of Aenos Mt and subsequent rockfalls took place north of the village. Many boulders fell on its houses, resulting in considerable non-structural and structural damage, as well as panic and anxiety in residents [20]. Large boulders fell in the road network of the area, resulting in the temporary disruption in traffic and communication with other villages. Kolaitis village was completely destroyed by rockfalls [20]. In Arginia village, rockfalls were also generated, though without impact on buildings and infrastructure [20]. Close to Chionata village, boulders detached from the adjacent steep limestone slopes, resulting in rockfalls [20]. Based on newspaper reports (I I MERA, 13.08.53), the boulders crushed buildings, resulting in heavy damage as well as many fatalities and injured people. In Plateies area, rockfalls were triggered along slopes of Aenos Mt composed of limestone [20]. These rockfalls claimed a life in the northeastern part of Plateies village, at the crossroads of the Eleios-Pronnoi area. Rockfalls and landslides were also generated at the southeastern part of Cephalonia (Figure 11). Skala area was affected and was cut-off for days, due to the accumulation of the mobilized material on the road network (TAXYDROMOS, 14.08.1953). A large part of the village suffered damage from these failures (NEOLOGOS PATRON, 14.08.1953). These phenomena were repeated during the aftershock period and especially by a large aftershock occurred 5 days later, on 17 August (TA NEA, 19.08.1953). Northeast of the affected Skala area, rockfalls were generated close to Anninata village and contributed to the complete destruction of the village (TAXYDROMOS, 14.08.1953). Slope failures occurred in Argostoli area (Figures 10e and 11). Boulders detached from the slopes of kilns close to Argostoli threatened many workers, fortunately without losses and injuries (I I MERA, 14.08.1953, 16.08.1953). Rockfalls were also triggered in Faraon Hill [16], in Lassi area (Figure 11), and they were activated many times during the aftershock period (NEOLOGOS PATRON, 14.08.1953, 15.08.1953; PELOPONNISOS, 14.08.1953; I I MERA, 15.08.1953). Slope failures were also generated in Paliki peninsula (Figures 10e and 11). In particular, in Ntouri (Paliokastro) hill, located north of Lixouri, where the ancient fortified city of Pali is located, rockfalls were generated. The falling material affected the vegetation of the area, as rolling blocks destroyed olive trees. Moreover, rockfalls were triggered at the southeastern part of Paliki.