The Disappearance of Helike-Classical Greece—New Remote Sensing and Geological Evidence

• Published in: Remote sensing (Basel, Switzerland) Vol. 7; no. 2; pp. 1263 - 1278
• Main Authors: Ferentinos, George, Papatheodorou, George, Geraga, Maria, Christodoulou, Dimitris, Fakiris, Elias, Iatrou, Margarita
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 2015
• Subjects: Boreholes; coastal/nearshore landslide; Corinth Gulf; Deltas; Earthquakes; Geohazards; Geological hazards; Geological surveys; Gulfs; Helike city; Historic; Landslides; Liquefaction; Remote sensing; Seismic activity; side scan sonar; subbottom profiler
• ISSN: 2072-4292; 2072-4292
• DOI: 10.3390/rs70201263

Helike, the Achaean Dodecapolis capital, in the Corinth Gulf, Greece, was, according to historical sources, devastated and disappeared from sight during an earthquake followed by sea invasion on to land in 373/372 B.C. A marine remote sensing survey, which was carried out to examine a landslide following a 6.2 R earthquake in 1995, that affected the coastal and near-shore delta plain zone on which Helike stood, accompanied by onshore borehole data, enabled us to postulate the geological processes leading to the Helike catastrophe. Helike was initially leveled during a 6 to 6.7 R earthquake; it is postulated to have then submerged following a translational landslide caused by liquefaction. This Helike catastrophe model is consistent with historical sources and current views regarding the expected geological hazards magnitude in the Gulf.