The AD 365 earthquake. From legend to modelling


Published: Jan 1, 2001
Keywords:
Eastern Mediterranean uplifted coasts AD 365 earthquake tsunami elastic dislocation analysis fault modeling
Α. Γ. ΔΡΑΚΟΣ
Σ. Κ. ΣΤΕΙΡΟΣ
Abstract

A major earthquake shook the entire East Mediterranean region on July 21st AD 365; numerous cities were completely ruined or seriously damaged, while a tsunami that followed destroyed the Nile Delta. This disaster impressed ancient writers for more than 1000 years and it turned to a legend. Despite the fact that the AD 365 earthquake is probably the greatest one that took place in the East Mediterranean region in the historic period, it has not been studied in detail. The main reason is that the historical data are poor, ambiguous and contradictory, and do not permit any secure seismological conclusions. Yet, many workers have concluded that this earthquake was associated with a fault along the Hellenic Arc, SW of Crete, in agreement with geomorphological, biological and radiometric data indicating that the western part of the island was uplifted by up to 9m by an earthquake in the 4th century AD. New archaeological data permit to shed more light to this earthquake and to identify its meizoseismal area, extending from western Cyprus to the Libyan coasts. Furthermore, an elastic dislocation analysis of the earthquake uplift, deduced from coastal data, permits to conclude that the causative fault was an east-west striking inverse fault at least 100km long, southwest of Crete, associated with an earthquake of magnitude of the order of M=8.5-8.7.

Article Details
  • Section
  • Seismology
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