Destruction of the Ancient Cities of Dioscurias and Sebastopolis
due to Seismic Impacts

A. A. Nikonov

Schmidt Joint Institute of Physics of the Earth, Russian Academy of Sciences, Bol’shaya Gruzinskaya ul. 10,
Moscow, 123810 Russia

Received August 14, 1995

Abstract—Little-known archaeological data on the subaerial and submarine remains of the Greek city of
Dioscurias and the Roman city of Sebastopolis near the coast of Sukhumi Bay are used to elucidate the causes
of the destruction and disappearance of these ancient cities. Hypotheses of paleogeographic changes, submarine
slumping, inundation, and seismic impacts are discussed. It is concluded that the two cities were destroyed in
the beginning of the 1st century AD and in the middle of the 4th century AD, respectively, as a result of cata-
strophic earthquakes of intensity 9, which were accompanied by considerable subsidence of a portion of the
coast and the bay floor.