Synchronized earthquake occurrence in the Hellenic Arc and implications for earthquake prediction in the Dodecanese Islands (Greece)

Abstract

Seismicity data from 1800 onwards show that large ( M s 7–7.5) shocks in the Western Hellenic Arc are followed on a one-to-one basis by events of M s 6.7–7.5 in the Dodecanese Islands, in the Eastern Hellenic Arc, occurring at a mean distance of 620 ± 102 km from the earlier event after a mean time lag of 2.5 ± 1.7 years. A plate tectonic interpretation is proposed. Should this phenomenon continue to be repeated, a new event of M s ~ 6.7 or larger can be expected to strike in the next few months along one of the two seismic fracture zones in the Dodecanese islands, given that the last large shock in the Western Hellenic Arc occurred 4.7 years ago, which is the maximum estimated time lag.