Abstract
In AD 552 the area around the Gulf of Corinth, Central Greece, was reportedly hit by large destructive earthquakes. At the same time a tsunami supposedly hit Maliac Bay. The case calls for a realistic interpretation since earthquake scenarios failed to explain rationally the narration of the contemporary Byzantine historian Procopius, the only literary source. Scholars have some doubts about Procopius’ reliability since he frequently copied classical authors. We found impressive similarities between the texts of Procopius and those by classic authors regarding the 426 BC central Greece tsunamigenic earthquake. Very likely the AD 552 Maliac Bay tsunami is a fake event in mimic of the 426 BC one. Sixth-century seismic disasters in southern Greece, reported away from the Gulf of Corinth have been attributed as a deus ex machina to the AD 552 earthquake(s) due to the lack of supporting literary sources. After critical examination of the Procopius’ narration and of relevant geological, seismotectonic, and archeological evidence, we concluded with a scenario comprising two strong (magnitude ~6.5) earthquakes but without tsunami generation. The first earthquake perhaps happened in Boeotia, NE Corinth Gulf, as palaeoseismological evidence also indicates. The second earthquake, in Patras-Naupactus area, western Corinth Gulf, is supported by convincing archeological findings. However, seismic destruction horizons in southern Greece are interpreted by distinct sixth-century earthquakes independent from the Procopius’ ones.
Keywords
Introduction
The Mediterrenean region is characterized by high seismicity, which is documented by a lot of instrumental and pre-instrumental earthquake records, such as geological and archeological observations, and literary sources. One of the most active areas in the Mediterranean region is central Greece, which hosts normal faults particularly along the tectonic rift of the Corinth Gulf (Figures 1 and 2). Famous archeological sites, such as those of Delphi, Olympia, Corinth, and Athens, are existent around that tectonic rift and exposed to the seismic hazard of the area. Therefore, this area attracts great interest among the geoscientific, historical and archeological communities. Pre-instrumental earthquake records are of significant value for better understanding the earthquake generation process and for assessing seismic hazard.


Geography of the study region and localities mentioned in the text. Key: AB = Alkyonides Bay, Al = Alopi, Ant = Antikyra, An = Ayios (St.) Andreas, Ar = Arachovitika, At = Athens, Ath = Ayios (St.) Thomas, CG = Corinth Gulf, Co = Corinth, De = Delphi, Ec = Echinus, El = Elis, Fi = Filiatra, Ga = Galaxidi, He = Helike, It = Itea, Ka = Katakolon, Kap = Kaparelli, Ky = Kynos, Kyp = Kyparissia, La = Lamia, Le = Lechaion, Li = Livanates, Me = Messene, Ms = Messolonghi, Ol = Olympia, Or = Orchomenos, Pe = Perachora, Ph = Pheia, Py = Pylos, RA = Rion-Antirrion strait, Sc = Scarphe, Sk = Skoutela, Ski = Skinos, Ti = Tithorea, Th = Thermopylae, Yp = Ypati.
Destructive earthquakes would have occurred in central Greece in AD 551/552. Texts of the contemporary Byzantine historian Procopius Caesareus are the only first-hand documentary sources available. Procopius narrated that the earthquakes caused human victims, great damage and co-seismic ground failures around the Corinth Gulf as well as a powerful tsunami in Maliac Bay, NW Evoikos Gulf (Figure 3) (an authoritative English translation of the relevant passages is included in Supplemental Material). However, it remains unexplained why the AD 552 earthquake activity was ignored by other competent Byzantine historians of the sixth century, with the only exception of Evagrius Scholasticus who just copied Procopius in brief.

Seismotectonics of the the Gulf of Corinth and the North Evoikos Gulf (NEG). Primary and secondary faults, represented by thick and thin lines, respectively, are redrafted from Roberts and Jackson (1991), Armijo et al. (1996), Ganas et al. (1998), Moretti et al. (2003), Sakellariou et al. (2007), Zygouri et al. (2008), and Cundy et al. (2010). Arrows to the north of Gulf show GPS-based velocity vectors of crustal deformation (after Avallone et al., 2004; Briole et al., 2000; Clarke et al., 1997; Hollenstein et al., 2008): long arrow = 1.5 cm/year, short arrow = 1.0 cm/year. Star and the left-lateral strike-slip show the epicenter and the rupture mode associated with the strong (Mw 6.4) earthquake of 8 June 2008 in NW Peloponnese. Triangles in the easternmost side of the Gulf of Corinth show epicenters of the 1981 seismic sequence (Papazachos et al., 1984): solid triangle = mainshock of 24.2.1981, semi-solid triangle = large aftershock of 25.2.1981, open triangle = large aftershock of 4.3.1981 (Figure 4 plots a bit different epicentral locations determined by other authors for reasons of comparison). Large solid circles represent localities hit by the Procopius’ AD 552 earthquakes: PA = Patras, NA = Naupactus, CH = Chaeronia, CR = Coronia, SO = Schisti Odos. The two elliptical areas illustrate the suggested rupture zones associated with the AD 552 earthquakes with estimated magnitudes of ~6.5. Geography key: MB = Maliac Bay, At = Athens, Co = Corinth.
The Procopius’ earthquakes are of particular interest for several reasons. First is the the issue of the seismic and tsunami hazard assessment in central Greece. This area hosts Athens, the capital city of the country (Figure 3), other important cities and various critical infrastructures around the Gulf of Corinth, all being exposed to the seismic hazard.
Although some earthquake scenarios have been proposed so far (e.g. Galanopoulos, 1981; Guidoboni et al., 1994; Papazachos and Papazachou, 1997, 2003), the Procopius’s narration raises some important issues, which have not been adequately examined so far. Of substantial significance is to understand how many earthquakes occurred, also where and when they ruptured. Moreover, which earthquake caused the devastating tsunami in Maliac Bay? In addition, is the Procopius’ narration reliable? Is it supported by independent archeological and geological evidence? In this paper we first reexamine the AD 552 earthquakes and tsunami by focusing on the previous main issues. Then we conclude with a preferred seismic scenario based on archeological and geological evidence and on literary sources.
A thorough historical analysis (Evagelatou-Notara, 1987/1988; Guidoboni et al., 1994) showed that the earthquakes in question very likely occurred in AD 552. Quoting other authors who reported otherwise, for example AD 551, for example Papazachos and Papazachou (1997, 2003), we simply write “AD 551/552.”
Seismotectonic setting
The Gulf of Corinth is characterized by normal faults trending nearly E-W with an uplifted footwall in the south and a subsiding hanging wall with antithetic faulting in the north (Armijo et al., 1996; Jackson et al., 1982; Moretti et al., 2003; Sakellariou et al., 2007; Zygouri et al., 2008; Figure 3). The north Evoikos Gulf, between Greek mainland and Euboea (Evia) is dominated by nearly WNW-ESE trending normal faults (e.g. Cundy et al., 2010; Ganas et al., 1998; Roberts and Jackson, 1991). In the Gulf of Corinth, regional geodetic extension rates range from 1.0 cm/year up to about 1.5 cm/year (Avallone et al., 2004; Briole et al., 2000; Clarke et al., 1997; Hollenstein et al., 2008), which is consistent with seismic slip rates of ~1.0 cm/year (Ambraseys and Jackson, 1997; Papadopoulos, 1989). Extension strain rates of 250 nstrain/year (or 2.5 mm/year) have been estimated from GPS measurements (Hollenstein et al., 2008).
In central Greece, the upper earthquake magnitude bound, which is at Mw ~ 7.0, is controlled by the maximum length of fault segments being ~20 km (Ambraseys and Jackson, 1990; Roberts and Jackson, 1991; Valkaniotis and Pavlides, 2016). Earthquakes with estimated magnitudes not exceeding ~7.0 have been documented in various literary sources (e.g. Evagelatou-Notara, 1987/1988; Galanopoulos, 1981; Ambraseys, 2009; Ambraseys and Jackson, 1990, 1997; Guidoboni and Comastri, 2005; Guidoboni et al., 1994; Papadopoulos et al., 2000a; Papazachos and Papazachou, 1997, 2003; Stucchi et al., 2013). In the instrumental era, the Corinth rift experienced several strong earthquakes, for example on 24 February 1981 (moment magnitude Mw 6.4) that ruptured eastern gulf (Jackson et al., 1982) (Table 1 and Figure 4). In north Evoikos Gulf, a large earthquake (Mw 6.9) occurred on 27 April 1894, which was preceded by another strong earthquake (Mw 6.4) a few days earlier (Ambraseys and Jackson, 1990).
List of the strong shallow earthquakes that occurred in central Greece since AD 1850.
Focal parameters (φN = geographic latitude, λE = geographic longitude, Ms = surface-wave magnitude, Mw = moment magnitude) have been adopted from Papadopoulos et al. (2000a; Pa), Ambraseys and Jackson (1997; AJ97), and Makropoulos et al. (2012) for the events numbered 1–9, 10–11, and 12–22, respectively. For the earthquakes of 1995 and 1999 specific studies have been published by Bernard et al. (1997) and Papadopoulos et al. (2000b; Pb) but their focal parameters determinations are not substantially different from the adopted ones. Estimates of maximum intensity, Imax, in the 12-grade modified Mercalli-Sieberg scale, have been adopted from Pa, AJ97, and Pb for the events numbered 1–9, 10–21, and 22, respectively. For the earthquakes numbered 19 and 20 reliable estimation of Imax has not been possible due to the cumulative effects of the earthquakes 18, 19, and 20. Epicenters of the earthquakes listed in this table are illustrated in Figure 4.

Epicenters of strong earthquakes that occurred in the Gulf of Corinth (CG) and North Evoikos Gulf (NEG), central Greece, since AD 1850 (Table 1). Open and solid symbols represent earthquakes of surface-wave magnitudes ranging from 5.9 to 6.4 and from 6.5 to 6.9, respectively. Figures above symbols correspond to earthquake numbering in Table 1.
The tsunami rate in the Gulf of Corinth is remarkably high (Papadopoulos, 2007, 2009) due to that tsunami waves are caused not only by co-seismic fault dislocations but also by seismic and aseismic coastal and submarine landslides (Ambraseys, 1962, 2009; Antonopoulos, 1980; Galanopoulos, 1960; Galanopoulos et al., 1964; Kontopoulos and Avramidis, 2003; Kortekaas et al., 2011; Papadopoulos, 2007; Papadopoulos et al., 2014a; Papadopoulos and Chalkis, 1984). In Evoikos Gulf, however, the tsunami rate is much lower (Papadopoulos and Chalkis, 1984). A strong tsunamigenic earthquake documented in classical sources occurred either in 426 BC or alternatively sometime during the third century BC (Papaioannou et al., 2004).
Historical documentation
The documents
Procopius, who serviced in higher administrative positions in the imperial office, remains the most widely-read chronicler of the Justinian reign (Brown, 2008). He wrote three books: History of the Wars, Anekdota or Secret History, and On the Buildings. History of the Wars, consisting of eight books, very likely is dated to AD 551 or 552, with the exception of the eighth, which was published in ca. AD 554/557 (Brown, 2008). The majority’s opinion is that Procopius wrote Anekdota in ca. AD 550/551, that is 32 years from the accession of Justin in AD 518 (Greatrex, 1994, 2003; Haury, 1891). Anekdota remained unpublished until the Justinian’s death in AD 565. The book On the Buildings was written in AD 554 or possibly in ca. AD 560 (Brown, 2008).
Earthquake dating
Dating the Procopius’ earthquakes is inferred from historical events preceding and following the earthquakes. Mallet (1853) dated an earthquake in AD 552. However, many subsequent authors agreed that it happened in AD 551, for example Galanopoulos (1981), Papazachos and Papazachou (1997, 2003). Evagelatou-Notara (1987/1988), a careful historian, supported that the earthquake date was confused with that of the tsunamigenic AD 9 July 551 earthquake, that struck Lebanon and Palestine. The historian concluded convincingly that the Procopius’ earthquake(s) should be dated on May or June AD 552. Nevertheless, this does not match fully dating needs since Procopius speaks about “earthquakes,” that is about more than one seismic events. Besides, the Greek expression Ἐν τούτῳ δὲ τῷ χρόνῳ used by Procopius does not explicitly mean In that particular year but it may rather mean In that time period. This implies that the earthquakes may have taken place before or after AD May/June 552. Consequently, the earthquake dating issue remains open to some extent.
How many earthquakes occurred?
Earthquake dating is directly related to how many earthquakes happened. The plural term earthquakes used by Procopius is not amenable to an unequivocal interpretation. For example, a cluster of more than one separate mainshocks may have taken place in a short time window, say a few months or weeks. From seismological point of view this is absolutely realistic. Clusters of strong earthquakes occurring in such short time intervals have been recognized in many seismogenic areas of the world, including Greece (e.g. Papadopoulos et al., 2009). Alternatively, more than one strong earthquakes may have taken place, within a single foreshock-mainshock-aftershock sequence occurring in a short time interval. A characteristic example is the AD 1981 eastern Corinth Gulf sequence comprising three strong, destructive earthquakes (Jackson et al., 1982) (Table 1 and Figure 4).
Where the seismic sources have been located?
A reasonable reply to this issue may help in better understanding not only where the earthquake sources were possibly located but also how many strong earthquakes occurred.
Chaeronea-Coronea and Patras-Naupactus
The book on Wars provides information about the spatial distribution of the earthquake impact, which comprised loss of life, damage and ground failures. According to Procopius the earthquakes(s) affected the area around the Crissaean (Corinth) Gulf. However, from the countless towns and eight cities that were reportedly affected, Procopius named only four: Chaeronea and Coronea in Boeotia, Patrae (modern Patras), and Naupactus in western Corinth Gulf (Figure 3), where great loss of life was also reported. Due to the vicinity between Chaeronea and Coronea as well as between Patras and Naupactus, we may infer that destruction occurred mainly in two isolated spots.
Schisma
Procopius says that in the two towns around the so-called Schisma (Σχίσμα), the Cleft, a tremendous earthquake happened causing more loss of life than in all the rest of Greece. The locality of Schisma very likely was nothing else than the famous Σχιστή Οδός (Schisti Odos-the Cleft Road). Pausanias (second century AD; II, V.3 and II, 09596836221138330V.8) located it at the passage from Chaeronia to Delphi (Figure 3). In Sophokles’ tragedy Oedipus Tyrant (line 733), Schisti Odos was mentioned as the place where Oedipus killed his father. The narrow passage of Schisti Odos should be placed at the 137th–139th km of the modern Athens-Delphi road. This interpretation implies that Chaeronea and Coronea very likely were the two towns around Schisma, implying that Schisma should not be considered as an independent seismic source.
Procopius narrates that the ground was split open in many places with the formation of ground chasms. The appearance of co-seismic surface fault traces is a frequent ground failure in the epicentral areas of strong shallow earthquakes. In the Mediterranean, the ratio of shallow earthquakes with surface-fault trace increases with the earthquake size and approaches unity for magnitude ~7.2 (Konstantinou et al., 2005). The description that some of the ground openings “came together” implies fissures in loosed soil material that closed soon after the strong earth shaking. On the contrary, permanent openings may represent surface-fault traces similar to the ones observed in association with the 1981 seismic sequence.
Maliac Bay
According to Procopius, a sudden sea inundation happened in Echinus (Achinos) and Scarphe (Figure 2). As the wave penetrated inland, deluged the towns there and leveled them immediately, implying that important runup occurred. The mainland was flooded for a long time as far away as the mountains which rise there. Because of this, people were able to walk up to the islands in the bay since the sea water had abandoned its proper place. When the sea returned to its normal place fishes were left behind. The tsunami narration is realistic insofar as it describes features observed in many modern tsunami inundations. A puzzling issue, however, is that Procopius did not mention which of the earthquakes caused the tsunami.
Corinth
Although is generally thought that the AD 552 earthquakes damaged Corinth, there is no supporting evidence whatsoever to suggest that the city was really affected (Sanders, 2003 and references therein). Anekdota reports that Corinth was among the cities which at that time were overthrown by earthquakes. Procopius did not date the event but noticed that the earthquakes followed by a plague, which is dated in AD 542 (Downey, 1935). The earthquakes happened by the end of the period “when Justinian was administrating the Roman State of Regent, and later when he held the imperial office,” that is between AD 518 and 527 (Downey, 1935). Evagelatou-Notara (1987/1988) suggested that the Corinth earthquake happened very likely in AD 524/525. The Syrian Chronicle of Elias Nisibis says that an earthquake ruined large part of the Corinth walls in AD 543 (Guidoboni et al., 1994). However, Elias, when writing about a Corinthian earthquake, perhaps was thinking of the large earthquake that razed Cyzicus, Asia Minor, in AD 543.
Patras
Fallmerayer (1830) claimed that because of the AD 551/552 earthquake the New Corinth buried along with its inhabitants while the Isthmus fortress ruined, and in Patras 4000 citizens were buried under collapsing houses. This information was reproduced uncritically by later authors (Bon, 1951; Hertzeberg, 1902; Triantafyllou, 1995). However, Fallmerayer (1830) failed to document his claims.
Other cities
Several authors included other places around Corinth Gulf that supposedly hit by the AD 552 earthquake(s) (for localities see Figures 2 and 3). Ηowever, no relevant evidence has been provided. Brown (2008) included Delphi and speculated that “like the quake of 365 AD, it [the Procopius’ tsunami] may have flooded Lechaion, but it is unlikely to have destroyed the city.” However, Lechaion, situated to the west of Corinth, is not historically mentioned as being flooded by none of these tsunamis (Kolaiti et al., 2017). There is no plausible mechanism explaining how the AD 552 Maliac Bay tsunami would be capable to propagate up to Lechaion given that Maliac Bay is not physically connected to Corinth Gulf.
Allochthonous marine sediments intersecting quiescent harbor deposits combined with geoarchaeological destruction layers and extensive units of supposedly tsunamigenic beachrock were interpreted as representing a strong tsunami that destroyed Lechaion in association with the AD 521 or 552 earthquakes (Hadler et al., 2011). Such an interpretation, however, is highly speculative not only because of the questionable tsunamigenic nature of the beachrock but also since biostratigraphic analysis is lacking as a substantial indicator of the tsunamigenic origin of allochthonous marine sediments. Besides, neither geological observations nor historical documents support the generation of such a tsunami (Mourtzas et al., 2014)
The reliability issue
Procopius is generally considered as one of the most reliable Byzantine historians. An enigmatic point, however, is why such a series of tremendous earthquakes, like the AD 552 ones, escaped the attention of contemporary or later Byzantine historians, such as Agathias, Malalas, Theophanes, and Cedrenus. Per contra, they reported on other earthquakes occurring in the early Byzantine era and particularly during the sixth century. Evagrius was the only exception as pointed earlier. This historical paradox raised doubts about Procopius’ reliability (e.g. Cameron, 1985; Croke and Crow, 1983; Downey, 1947; Evans, 1970; Scott, 1985). Downey (1947) reported on Buildings as a panegyrical work of imperial propaganda. Cameron (1985) argued that Procopius must be read with extreme care, and his claims can be accepted only after thorough independent corroboration. Procopius introduced extensive credited and uncredited quotations from classical authors (Brown, 2008; Kaldellis, 2004), including Herodotus, Thucydides, Plato, and Strabo. According to various scholars (e.g. Hunger, 1969; Morrisson, 2007), Procopius used to imitate classical authors. For example, regarding the bubonic plague of spring AD 542 that reached Constantinople, our best diagnostic of the desease comes from Procopius, who used Thucydides’ report of the Athenian plague of 431 BC as his literary model (Evans, 2000).
Scholars remain skeptical about the drastic change in the writing style of Procopius from Buildings, where he appeared as a warm supporter of Justinian’s governorship, to Anekdota, where Procopius’ support turned to strong accusation against the emperor who then was considered responsible even for the earthquakes and other calamities that hit the empire. In Buildings, Justinian is the ideal king. Since Thermopylae was the key to the defense of southern Greece, Procopius produced a grandiose report of Justinian’s defense works at that famous pass (Evans, 2000). However, 14C dating on lime mortar samples has shown that most of the monumental work at Thermopylae, credited to Justinian on Procopius’ authority, was built about a century earlier (Cherf, 1992). In the Byzantine empire the disintegration of the cities started in the sixth century and was caused by the combined action of invasions and natural disasters including earthquakes (Saradi, 2006). In Anekdota, Justinian is the tyrant and, far from being inspired by God, he is the king of the devils, who is responsible not only for high taxes and rapacious officials, but also for the natural calamities fell on the empire: “God, hating the works of this demon emperor, turned His face away!” (Evans, 2000: 164).
Features of unreliability and tendency to imitate classical authors can be found in the Procopius’ narration of the AD 552 earthquakes too. It has passed unnoticed so far that the Procopius’ text reminds in many points classical texts by Thucydides (3,89.1-5), Strabo (1,3,20), and Diodorus Siculus (XII, 59.1-2), which provide descriptions of another famous, tsunamigenic earthquake that hit central Greece in 426 BC (e.g. Guidoboni et al., 1994). According to Thucydides the earthquake activity very likely started during the winter of 427 BC when Athens, Euboea, and Orchomenos in Boeotia, were hit by the earthquake. A first coincidence is that Orchomenos (Figure 2) is situated very close to Chaeronea and Coronea, reportedly hit by the AD 552 earthquake as well. According to Strabo, at the very time of the 426 BC earthquake the Thesmophoria festivity was taking place. Strangely enough a similar celebration was also going on when the AD 552 earthquake(s) occurred. Procopius, however, failed to specify the locality and time of that incidence. We evaluate that it is of low likelihood for such coincidences to come true just by chance.
An additional point of strong doubt regards the Maliac Bay tsunami. According to classical authors, because of the 426 BC earthquake a tsunami inundated coastal zones in Maliac Bay. In AD 552 the coasts of Maliac Bay were also reportedly inundated, which is another impressive coincidence. Procopius narrates that dead fishes were left behind after the sea water retreat. This phenomenon has been experienced many times after historical and modern tsunami inundations. But neither Strabo nor Thucydides nor Diodorus included such a picture in their narrations of the 426 BC tsunami. Then, one may wonder how it was possible for Procopius to be aware of such a possibility unless a tsunami had really happened. However, in another passage of his book, Strabo (16, 2, 26) says that dead fishes left behind after a tsunami hit violently between Tire and Ptolemais in Phoenicia, Levantine Sea, around 138 BC (Triantafyllou et al., 2022). We consider that very likely no tsunami was generated in Maliac Bay in AD 552, Procopius just imitated classic authors.
Archeological evidence
Tithorea
The early Christian basilica of St John the Theologian (Figure 2) is dated to the middle years of the fifth century (Yalouri, 2004). The makeshift repair of the basilica, with the meager means available, can be dated to the second half of the sixth century and, therefore, we may not rule out that the basilica perhaps was damaged by the AD 551/552 earthquake (Yalouri, 2004).
Corinth
Archeological excavations revealed seismic destructions in two basilicas in Skoutela (Pallas, 1957) and in Kraneion (Pallas, 1978) close to Corinth (Figure 2). Therefore, Evagelatou-Notara (1987/1988) included Corinth in the damage zone of the AD 552 earthquake. However, this is not justified since the independent archeological evidence remains insufficient to date the seismic destruction. This is also the case of the earthquake that reportedly caused damage to the Isthmus wall. The book on Buildings asserts that Justinian rebuilt the old trans-Isthmus wall, the rebuilding belonging to the years after AD 550. Earthquake damage made reconstruction necessary, it appears, and it may have been the AD 551/552 earthquake that was responsible (Evans, 2000). On the other hand, numismatic findings in destruction horizons documented in field notebooks, reports and research publications (Adelson and Kustas, 1964; Broneer, 1926; Dengate, 1981; Scranton, 1957), indicated that Corinth was possibly destroyed by earthquakes around AD 580 and in the period from AD 597 to 601 (Evagelatou-Notara, 1987/1988). Summarizing, the archeological evidence available supports that the seismic destruction of Corinth was due rather to the earthquakes of AD 524/525, 543, 580, and 597–601 than to the AD 552 ones.
Antikyra
In northern Gulf of Corinth, the Antikyra town (Figures 2 and 3) was supposedly destroyed by the AD 552 earthquake. This is based on preliminary archeological evidence indicating a seismic destruction horizon in the early Christian settlement of modern Palatia (Koureda-Raptaki, 2004). However, the destruction episode is poorly dated and might be correlated to several seismic events: AD 524/525, 543, 552, 580, and 597–601. Besides, evidence based on numismatic dating indicates that Antikyra was still standing by the end of sixth century before its seismic destruction (Tsourti, 2004). Possibly an earthquake unknown from literary sources destroyed Antikyra likely after ca. AD 590. However, no evidence is available to support such a hypothesis. In the instrumental period of seismology, a strong earthquake (Mw 6.0) occurred in Antikyra on 8 April 1970 (Table 1).
Patras
In Patras area (Figure 3), excavation of a Roman building showed that it likely destroyed by an earthquake during the sixth century (Papapostolou, 1978). The ancient acropolis of Patras (Kastro) perhaps was destroyed by the same earthquake (Georgopoulou-Verra, 2002). The previous authors attributed these destructions to the AD 552 earthquake(s).
Again in Patras, a burial complex of early Christian date was excavated as part of the south-west cemetery of the ancient city (Koumousi-Vyenopoulou, 1996). The excavator supposed that the presence in the graves of marble closure slabs dated in the AD fifth century, presupposes the destruction and abandonment of the churches in the town from which they came, and the pairs of contemporary double burials points to a high death rate caused by some natural disaster that struck the town. Koumousi-Vyenopoulou (1996) concluded that the excavation associates the creation of the cemetery with the burial of the victims of the AD 552 earthquake. The archeologist reported on published evidence indicating destruction in Elis and Corinth, in NW and NE Peloponnese, respectively (Figure 2). Although the archeological evidence for a likely seismic destruction in Patras is rather convincing, the time window does not fit well the time of the Procopius’ earthquake(s).
In Palaeomonastiro of Arachovitika village, about 15 km to the NE of Patras (Figure 2), evidence was found that a palaeochristian building complex was destroyed by an earthquake during the AD sixth century, which possibly was the AD 551/552 one (Georgopoulou-Verra, 2004). In Ayios Ioannis (St John) area near Messolongi (Figure 2), where the ancient Alikyrna was situated, a complex of Roman Therme (baths) was destroyed by a strong earthquake, possibly the AD 551/552 one (Petropoulos, 2002). The seismic disaster dating appears secured since AD sixth century lamps were found at the baths’ ground.
SW Peloponnese
The excavation of a palaeochristian basilica near St Kyriaki in Filiatra, Messenia province (Figure 2), showed that it was rebuilt after it had been partly ruined very likely by earthquakes (Pallas, 1962). Following Gardiner (1925), the excavator supported that a likely post quem terminus was determined from a similar case in Olympia and possibly in Patras occurring in AD 522 or in 551/552, while numismatic dating indicates AD 582–602 as the ante quem terminus for the basilica reparation. Themelis (2002) tentatively suggested that reparation works recognized in buildings of Messene town, SW Peloponnese (Figure 2), perhaps are related to the AD 522 and 550/552 earthquakes. Papadopoulos et al. (2014b) supported that earthquakes occurring around the Gulf of Corinth are uncapable to produce destruction in SW Peloponnese places situated as far as ~200 km away.
Geological evidence
Olympia
The classical archeological site of Olympia in Elis province, NW Peloponnese (Figure 2), has been extensively discussed as regards its possible destruction not only by earthquakes and other natural disasters but also by human actions. Such events were placed particularly during the AD sixth century. Αdler (1897) suggested that the Zeus Temple and other antiquities were destroyed by strong earthquakes in AD 522 and 551/552. The only reasoning was that these earthquakes were the only known from the AD sixth century period. Gardiner (1925) noticed the Peloponnese suffered from violent earthquakes in the years AD 522 and 551 but we do not know which of the two overthrew the columns of the Temple of Zeus.
Hermann (1962), Ashmole and Yalouris (1967), and Meyer (1979) just repeat Gardiner’s (1925) suggestion. A reappraisal of the earthquake destruction in Olympia was elaborated by Sinn (1992) who concluded that, evidence for damage and reparation in buildings dated around AD 270 should be attributed rather to serious seismic action than to the invasion of Heruli. Later on, during the fifth and sixth centuries a flourishing town was developed there but the active commercial life of the settlement ended with the “known earthquake,” which destroyed also the Zeus Temple. We suppose that the AD 552 earthquake was meant. Reicherter (2011), based on the domino-style fallen columns, supported that the Zeus Temple was destroyed by an early fourth century earthquake, although the possibility that the destruction could be correlated with either the AD 522 or the 551/552 earthquakes has not been ruled out.
Summarizing the Olympia case, we may conclude that certainly there is evidence of seismic damage imprinted on structural elements of the monuments. However, neither observational documentation, for example dating results, nor literary sources are available to specify individual earthquake event(s), for example the AD 552 ones, that may have caused damage.
Pheia
Pheia, the sea port of Olympia (Figure 2), is also of interest to our analysis since it was considered as being affected by the AD 551/552 earthquake. Based on a preliminary archeological survey in the sea bottom, Yalouris (1960) suggested that Pheia submerged and destroyed due to the AD sixth century strong earthquake that hit Patras, Olympia and the entire NW Peloponnese. We suppose that the Procopius’ AD 552 earthquake(s) is meant once more. Based on Yalouris (1960), Kraft et al. (2005) extended the hypothesis and claimed that the sixth century earthquake resulted not only in subsidence of the coastal portion of Pheia but comprised uplift of the flanking hill of modern Katakolon (Figure 2). Such a hypothesis, if valid, has the important consequence that the impact area of the AD 552 earthquake should not be placed in central Greece but in the coastal zone of Elis facing the Ionian Sea, in contradiction to the Procopius’ narration. An alternative would be that another strong earthquake occurring in Elis during the AD sixth century was responsible for the ubrupt co-seismic faulting. But this point of view stands as only a working hypothesis due to the lack of historical correlation. Besides, the suggested seismotectonic displacement in Katakolon has not been documented by palaeoseismological evidence, such as stratigraphic correlations.
Of relevance is the Olympia tsunami hypothesis introduced by Vött and Brückner (2011a) with the aim “to clarify the mystery of the rapid burial of Olympia under 4–6 m of sediments after the sixth century AD and subsequent erosion of the Kladeos River by 8–10 m down to the ancient flow level.” Based on detailed sedimentological, geophysical, geochemical, and microfaunal analyses, these authors concluded that the Kladeos River valley and Olympia (Figure 2) experienced at least four distinct phases of catastrophic high-energy flood events attributed to multiple tsunami impact. They put forward the hypothesis that the cult site of Olympia was rather destroyed by tsunami than by fluvial processes related to the Kladeos River. Since a charcoal fragment from a fining upward sequence out of sand and gravel deposited under high-energy conditions was 14C AMS (Accelerator Mass Spectrometry) radiocarbon dated to cal year AD 585–647, at the 2σ interval, Vött and Brückner (2011a) supported that this dating result fits the AD 551/552 earthquake.
The results per se do not yield evidence for the AD 552 earthquake. Moreover, the earthquake of AD 552 stands at time distance of 33 years from the lower limit of the radiocarbon tsunami dating window. From geological standpoint the tsunami is weakly documented and, therefore, Vött and Brückner (2011a) speaks only about a hypothesis. Besides, these authors recognized that there are no historical accounts on catastrophic flooding of Olympia. Eventually, it is highly questionable whether even an extreme tsunami would be capable to run such a long distance inland as to reach ancient Olympia and cause destruction there. Such an important issue could be met with numerical tsunami simulations which, however, fall beyond the scope of this paper. Today, the distance of Olympia to the closest shoreline is ~13 km. The argument does not change by considering that the ancient shoreline advanced by some 3 km to reach its present position due to the Alpheios River deposition (Kaupert and Dörpfeld, 1882; Yalouris, 1960).
In a more thorough study, Vött et al. (2011b) abandoned the Olympia tsunami hypothesis but presented detailed results to support that the coast of Pheia was inundated by three distinct tsunamis in the geological past. Based on geological and archeological observations those authors suggested that the most recent tsunami occurred in Byzantine to post-Byzantine period. To correlate the supposed tsunami with the AD 551/552 earthquake, Vött et al. (2011b) quoted Kraft et al. (2005) who, however, were based only on the Yalouris (1960) hypothesis without relevant documentation. Vött et al. (2011b: 262–263) stated that “The 551/552 AD earthquake is reported to have been related to a strong seismic sea wave which brought destruction to many coastal cities on the Peloponnese and the Greek mainland (Guidoboni et al., 1994).” However, one may find no such a statement in Guidoboni et al. (1994) who quoted carefully only the Procopius’ text which, as we have seen, does not speak about tsunami in Peloponnese but only in the Maliac Bay coast.
Such misunderstanding underlines the difficulty to interpret geological and/or archeological findings in the absence of supporting literary sources. Consequently, the time window for the occurrence of the supposed Byzantine to post-Byzantine tsunami in Pheia remains quite wide. In this context, the large tsunami of AD 365, which is a well-documented event from many points of view (see reviews in Ambraseys, 2009; Papadopoulos, 2011), remains as candidate for a possible interpretation of the tsunami traces found in Pheia. This has not been excluded by Vött et al. (2011b). However, they supported (p. 280) that “written sources are in favor of the year 551/552 AD when a seismic sea wave is reported to have hit the area,” which is not the case at all since no such reports are existent. Last but not least is whether the Pheia tsunami is geologically well documented. Examination of this issue goes beyond the scope of this paper but certainly should be examined thoroughly in the future by focusing on whether the sedimentary sequence in Pheia is of tsunamigenic origin or not.
A seismological approach
Past earthquake scenarios
Scenarios regarding the time, place and magnitude of the AD 552 earthquakes have been suggested by several authors in the past. Perrey (1848) and Mallet (1853), based on the chronological order of the historical events narrated by Procopius, dated the earthquake(s) in AD 552, thus distinguishing it from the AD 9 July 551 tsunamigenic earthquake that ruptured offshore Lebanon. Most of later authors, however, preferred to date these earthquakes in AD 551, with the exception of Evagelatou-Notara (1987/1988) who convincingly dated it again in AD 552. In early earthquake compilations one may also find earlier earthquakes dated in AD 521/522, alternatively in AD 524/525, as well as in AD 543 (e.g. Evagelatou-Notara, 1987/1988). Besides, numismatic evidence indicated the occurrence of earthquakes that hit Corinth in ca. AD 580 and 597–601 (Evagelatou-Notara, 1987/1988). Information about the earthquakes pre-dating and post-dating the AD 552 earthquakes is also useful for better understanding previous scenarios.
Earlier seismologists attributed the AD 552 seismic damage zone to a single earthquake megaevent (e.g. Galanopoulos, 1981; Mallet, 1853; Schmidt, 1879; Shebalin et al., 1974; Sieberg, 1932). This was followed by Guidoboni et al. (1994) who considered that a single tsunamigenic earthquake event occurred in AD 551/552 incorporating the entire region from Patras-Naupactus to Chaeronea-Coronea and to the Maliac Bay. Other authors interpreted Procopius’ text in the context of more than one events but no consensus has been reached so far. For example, Galanopoulos (1981) considered two separate events occurring in Patras-Naupactus area the first and in Boeotia the second. Papaioannou et al. (2004) added a hypothetical third earthquake in the Maliac Bay to account for the tsunami generation there. This approach was adopted by Papazachos and Papazachou (2003) who assigned earthquake magnitudes of 6.8 to the Maliac Bay and to the Chaeronea-Coronea earthquakes, and 6.5 to the Patras-Naupactus earthquake. However, magnitude assignment to hypothetical earthquakes is ungrounded. Ambraseys (2009) adopted also the occurrence of three earthquakes.
The various scenarios proposed suffer from two common problems. The first is that they ignore the geological and archeological evidence or make just a little use of it. The second is that those scenarios do not examine the reliability of the literary sources. In the next lines we evaluate critically the literaly sources and the various past seismic scenarios in the light of the seismotectonic regime of the region and in relation to the archeological and palaeoseismological findings particularly after the 1981 earthquake sequence in the eastern Corinth Gulf.
Palaeoerthquakes in the Eastern Corinth Gulf
The seismic sequence of 1981 has increased interest regarding the recurrence of strong earthquakes in the area. Predecessors of the 1981 (Table 1 and Figure 4) earthquakes were investigated particularly in the sites of Skinos and Kaparelli (Figure 3), where surface-fault traces were observed after the 24 February 1981 (Mw 6.4) and 4 March 1981 (Mw 6.2) earthquakes, respectively.
In Skinos, evidence for up to six past earthquakes was found in three palaeoseismological trenching sites (Collier et al., 1998; Pantosti et al., 1996). One of them was dated in a time window incorporating the AD sixth century. Combined calibrated Mean Residence Time (MRT) and AMS dating results, at 2σ, yield an age of AD 390–1015 and possibly in the time interval AD 590–1015. Other palaeoearthquake events postdate AD 670. In Kaparelli fault, at least three palaeoearthquakes were determined in trenches opened there (Kokkalas et al., 2007). The most recent was 14C dated at 2σ calibrated age of AD 560–690 (1390–1260 BP). Considering the results of Collier et al. (1998), Kokkalas et al. (2007) concluded that at least the most recent event may have ruptured both the south dipping Kaparelli fault and the north dipping Skinos fault (Figure 3) synchronously, resembling the 1981 earthquake sequence. These results, however, contradict the ones obtained by Benedetti et al. (2003), who performed 36Cl cosmic ray exposure dating in 4–5-m high limestone surface at two sites about 50 m apart in the Kaparelli fault scarp. They found that the Kaparelli fault ruptured three times prior to 1981 at 20 ± 3, 14.5 ± 0.5, and 10.5 ± 0.5 ka BP, with slip amplitudes between 0.6 and 2.1 m, and concluded that the fault has been inactive for 10,000 years prior to the 1981 event.
At the northeast edge of the Corinth Gulf, the 12-km-long Corini normal fault near Coronea (Figure 3), striking roughly NE-SW and dipping toward SE, crops out along the south slope of the Elikon Mountain (Ganas et al., 2018). This structure, which resembles similar kinematics with the active faults of the south coast of the Gulf of Corinth, perhaps is younger than 1 Ma years but no association has been established with strong historical earthquakes in the area (Ganas et al., 2018). Several earthquake horizons were revealed by mapping visual weathering features and cosmogenic 36Cl dating in Pisia fault (Figure 3) that was activated with the 1981 seismic sequence (Mechernich et al., 2018). At least six events with 0.25–1.1 m of coseismic displacement ruptured the Pisia fault within the last 7.3 ± 0.7 kyr but not later than ~2.0 kyr BP. The estimated moment-magnitudes of these events ranged from 6.2 to 6.7 (Mechernich et al., 2018).
Elevated shorelines representing co-seismic uplift were identified in Perachora peninsula and in Lechaion, eastern Corinth Gulf (Morhange et al., 2012; Pirazzoli et al., 1996; Figures 2 and 3). In Perachora, uplift of amplitude not exceeding 1.1 m were 14C dated at 1σ cal. age of AD 290–560. In Lechaion, the Roman harbor of Corinth, an uplift of over 1.2 m were 14C dated at 1σ cal. age of AD 442–657. The uplift amplitude at both Perachora and Lechaion is on the order of the 1981 co-seismic displacement. However, it has not been fully understood how such uplifts could be interpreted in the frame of the extentional tectonics that dominates Corinth Gulf. A possible explanation is that uplift partly occurred in the footwall of some faults of the area, while the rest is due to “regional” isostatic uplift independent of fault slip (Turner et al., 2010).
In summary, the radiodated time windows of the suggested co-seismic deformation recognized in Skinos, Perachora, Kaparelli, and Lechaion, are too wide to correlate with individual historical seismic events, such as the AD 552 one(s). Besides, the area of Boeotia, which according to Procopius’ text was hit by those earthquake(s), is situated well to the north from the eastern Corinth Gulf. This is an additional obstacle for possible correlations.
Seismological evaluation
The earthquake scenario for a single megaevent (e.g. Guidoboni et al., 1994) does not fit the literary source since Procopius clearly speaks about earthquakes. In addition, the main spots of damage, ground failures and tsunami occurrences, all considered as effects produced by a single megaevent, imply a quite large seismic rupture zone, with major axis extending from Patras-Naupactus to Maliac Bay at distance of more than 90 km (Figure 3). Empirical relationships between earthquake magnitude and seismic fault length, L, indicate that for L = 90 km the magnitude ranges from 7.2 to 7.6 (Table 2). This clearly exceeds the restriction of observed maximum magnitude, which in central Greece was found at 7.0 due to the relatively short fault segments (Ambraseys and Jackson, 1990; Roberts and Jackson, 1991; Valkaniotis and Pavlides, 2016). From the palaeoearthquake research as well as from the historical accounts (Table 1) no evidence for earthquake magnitude larger than Mw 7.0 has been found. Besides, no seismogenic structure as long as ~90 km is known in central Greece.
Empirical relationships used to estimate historical earthquake magnitudes from fault length.
Key: Mw = moment magnitude, Ms = surface-wave magnitude, L = length of subsurface seismic fault in km, SRL = length of surface rupture in km. For seismic fault length of 90 km considered in Section Seismological Evaluation, we calculated Mw = 7.4, Mw = 7.3, Ms = 7.6, and Ms = 7.2 from (1), (2), (3), and (4), respectively.
The seismotectonics dominating the Gulf of Corinth is clearly controlled by normal faults of about E-W direction (Figure 3). However, a single megaearthquake may have ruptured from southwest, at Patras-Naupactus area, to northeast at Maliac Bay. The single megaearthquake scenario with rupture zone striking SW-NE leaves without explanation the heavy damage reportedly caused in the Chaeronea-Coronea area, since this area is situated at considerable distance from a hypothetical seismic fault lineament connecting the Patras-Naupactus area with the Maliac Bay.
The single megaearthquake scenario becomes worst if one includes the archeological hypothesis that several spots in the provinces of Elis and Messenia, western Peloponnese, were also hit by the megaearthquake of AD 552. Then, the size of the candidate seismic impact zone, extending from Maliac bay to Messene, exceeds ~200 km, which is completely out of any seismotectonic reality for the region. Besides, Procopius did not name at all localities in Elis and Messenia provinces as being affected by the AD 552 earthquake(s). A consequence is that the seismic destruction horizons in those provinces should be interpreted by earthquake occurrences independently from the Procopius earthquakes. The lack of documentary sources, however, is a serious obstacle in the effort to determine specific seismic events, which could be considered as candidates for the realistic interpretation of the geological and archeological findings in those provinces.
The scenario involving two seismic sources, one in Boeotia and another in Patras-Naupactus, better fits the Procopius’ narration. This scenario covers the areas named by Procopius as being hit by the earthquakes. However, Maliac Bay is named as being affected only by a tsunami, the generation mechanism of which is hardly explainable with the seismic rupture zones in Boeotia and Patras-Naupactus. Consequently, a third local seismic source is needed to better explain the tsunami generation. But Procopius does not mention a local earthquake in Maliac Bay. One may not exclude that Echinus and Skarfia, in either sides of Maliac Bay, were destroyed by a local earthquake only a few minutes before the tsunami arrived. Thus, the destruction caused by the earthquake, if any, was masked by the destruction caused by the subsequent tsunami. However, no relevant evidence is in place.
The geomorphological change produced in Maliac Bay by the rapid deposition in the Spercheios river delta should not be ignored when considering the potential for tsunami generation. From the era of Persian wars, during the fifth century BC, up to the present time, the river deposition advanced the land for about 4–5 km (Perissoratis et al., 1997), which results in 1.5–2 km advancement of land from the Persian wars until the sixth century AD, if a uniform sediment deposition rate is roughly considered. Besides, the sea depth in Maliac Bay gradually decreased due to river sediments accumulation at the sea floor. Today, the maximum sea water depth in Maliac Bay does not exceed 24 m (Perissoratis et al., 1997). Due to the drastic decrease of both the sea surface and the thickness of the sea water column, the potential for strong tsunami generation in Maliac Bay was significantly low about 1000 years after the 426 BC tsunami.
A preferred scenario
Based on the previous analysis we consider that at all evidence the Maliac Bay tsunami was very likely an artifact in Procopius’ narration, just a mimic of the 426 BC tsunami. Besides, a tsunami inundation in the Maliac Bay coast is not supported by archeological or geological findings. On the other hand, from the available literary, archeological and geological evidence we consider as a likely scenario that in AD 552 two strong earthquakes, but without tsunami generation, ruptured the Gulf of Corinth, in the areas of Boeotia (Chaeronia-Coronea) and of Patras-Naupactus (Figure 3). The Patras-Naupactus earthquake case is supported by independent archeological findings, at least in Patras and its environs. However, the Boeotia earthquake case is less documented as compared to the Patras-Naupactus case. Apart from the Procopius’ narration we found no archeological evidence to support the earthquake case in Boeotia, with the exception of the little evidence from a damaged basilica in Tithorea. Yet, palaeoearthquakes identified in the eastern Corinth Gulf where the 1981 seismic sequence occurred, do not account adequately for a AD 552 Boeotia strong earthquake. The reason is that the palaeoearthquake trenching positions do not geographically fit the Chaeronia-Coronea area. However, we may not rule out that this area suffered some damage by a sixth century strong earthquake occurring to the south in the area of the 1981 seismic sequence.
Assuming that a strong earthquake occurred in Boeotia, regardless of the little support it takes from archeological and geological field observations, we may not exclude that Corinth was also damaged by such an event. However, this is only speculative since Procopius did not name Corinth among the cities affected by the AD 552 earthquakes.
Earthquake size
The estimation of magnitude, M, of historical earthquakes is usually based on the conversion of maximum seismic intensity, Imax, to M through empirical M/Imax relationships obtained from data sets of instrumental earthquakes (e.g. Ambraseys and Jackson, 1997). From Greek instrumental data sets, Papadopoulos (2011) established empirical Ms/Imax relationships for inland, coastal and offshore earthquakes; Ms is surface-wave magnitude, which for the magnitude range considered in this study is nearly equivalent to Mw. Two alternatives are appropriate for application in our case:
To estimate the magnitude of the AD 552 earthquakes we first followed the Procopius narration (see Supplemental Material) in order to assess the Imax level. Procopius says that “. . .cities were leveled to the ground. . . the earth was rent asunder in many places and formed chasms. . . there was a tremendous earthquake which caused more loss of life than in all the rest of Greece.”
Since the narration implies extensive destruction we assumed that the intensity Imax in Chaeronea-Coronea and in Patras-Naupactus ranged from IX to X in MMI (Modified Mercalli) intensity scale. Then, magnitude Ms = 6.4 and 6.6 was calculated from (1), while Ms = 6.4 and 6.7 was obtained from (2). This implies that earthquake magnitudes of Ms ~ Mw = 6.5(±0.2) might be adopted for each one of the two strong earthquakes in our preferred scenario. However, the magnitudes determined remain quite uncertain since the information available about the impact of the AD 552 earthquakes is limited.
Conclusions
The text of the contemporary Byzantine Procopius is the only first-hand source available on the strong earthquake occurrences in central Greece during AD 552. We found that the Procopius’ narration is in many points similar or even coincident to earthquake descriptions by Strabo and Thucydides. A characteristic example is the 426 BC tsunamigenic earthquake in central Greece. The Procopius’ description is likely exaggerated as regards the incident that so many people supposedly killed during a festivity event as exactly happened in 426 BC. Perhaps this is nothing more than an imitation of classical authors from the side of Procopius. The Procopius’ story about the destructive tsunami that inundated Maliac Bay, northern Evoikos Gulf, is not convincing at all, very likely being a fake, just a mimic of the one of 426 BC. At all evidence, Procopius’ narration is an amalgamation of real contemporary earthquake events, of exaggerated earthquake effects, and of fake “events,” the last being only mimises of classic authors.
Although Procopius reported that eight cities were hit, he named only Chaeronea-Coronea in Boeotia and Patras-Naupactus in the eastern and western Corinth Gulf, respectively. In view of the reliability issue regarding the Procopius’ narration, presented in a previous section, our preferred scenario includes two separate strong earthquakes but without tsunami generation. These earthquakes, with magnitudes estimated at ~6.5, may have ruptured the areas of Chaeronea-Coronea and Patras-Naupactus.
The Procopius’ narration is supported by convincing archeological evidence only in the area of Patras and its environs. However, no evidence was found for the claim of modern authors that 4000 victims were caused there, although archeological findings indicate massive death toll.
The scenario for a strong earthquake in Boeotia is poorly supported by archeological findings. Palaeoearthquakes identified geologically in the eastern Gulf of Corinth perhaps fit chronologically that scenario. However, such palaeoearthquake episodes should be placed to the south of Chaeronea-Coronea, thus weakening the case.
Our preferred scenario does not rule out that more than one strong earthquakes may have occurred either in Boeotia or in Patras-Naupactus or in both. However, there is no historical, archeological or geological evidence to support further such a hypothesis.
Corinth possibly experienced damaging earthquakes in AD 524/525, in 580 and from 597 to 601. An earthquake dated AD 543 is tentatively added in this list since it may have occurred in Cyzicus, Asia Minor, instead of Corinth. Nevertheless, we found no trustable literary, palaeoseismological or archeological evidence that Corinth was also affected by the AD 552 earthquake.
Several seismic and/or tsunami destruction horizons, identified in localities of western Peloponnese, including Olympia and Pheia in Elis province, as well as in Messene, Pylos and Filiatra in Messenia province, have been attributed to the AD 552 earthquakes. We concluded that such a link has been introduced rather as a deus ex machina perception, due to the lack of relevant literary sources, than as a documented interpretation. In several cases, however, the archeological findings are convincing as seismic destruction indicators and, therefore, need interpretation. From seismological point of view, a reasonable explanation would be that during the AD sixth century at least two earthquake events occurring in western Peloponnese, one in Elis and another in Messenia provinces, but independently from the Procopius’ earthquakes of AD 552, caused the seismic destructions found in those provinces. This approach is applicable to the case of Antikyra as well, north side of Gulf of Corinth, where an independent earthquake may have caused the archeologically determined seismic destruction which, however, remains poorly documented so far.
Supplemental Material
sj-docx-1-hol-10.1177_09596836221138330 – Supplemental material for The mid-6th century AD enigmatic mega earthquake and tsunami in central Greece: a seismotectonic, archeological, and historical reexamination
Supplemental material, sj-docx-1-hol-10.1177_09596836221138330 for The mid-6th century AD enigmatic mega earthquake and tsunami in central Greece: a seismotectonic, archeological, and historical reexamination by Gerassimos A Papadopoulos, Ioanna Triantafyllou and Andromachi Vassilopoulou in The Holocene
Footnotes
Acknowledgements
IT and GP contributed to the European Cooperation in Science and Technology COST project (2018-2023) “AGITHAR-Accelerating Global science In Tsunami HAzard and Risk analysis.” We are grateful to two anonymous reviewers for their constructive comments and corrections which contributed in improving the initial submission. Thanks are due to Mrs Antonia Papageorgiou for her assistance with the production of Figures 1 to 3 with the Generic Mapping Tools (GMT) software by Wessel and Smith (1991). Figure 4 was created using ArcGIS® software, version 10.8 by Esri.
Authors’ contributions
GP contributed with the conceptualization of the paper and collected literary sources. IT collected and evaluated earthquake and seismotectonic data and geological evidence, AV collected and evaluated historical and archeological evidence. All authors participated in the design of the study and drafted the manuscript, discussed results, reviewed the manuscript text, and gave final approval for publication.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Two authors (GP, IT) disclosed receipt of the following partial financial support: EU-FP7 research project ASTARTE (Assessment, STrategy And Risk Reduction for Tsunamis in Europe, 2013-2017), grant agreement no: 603839/2013.
Data accessibility
The datasets supporting this article are included in the paper.
Supplemental material
Supplemental material for this article is available online.
References
Supplementary Material
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