The Sunday morning quake measured 3.8 on the Richter scale and was felt in some of the taller buildings in Sochi, seismologists told Russia's RIA Novosti news service.
The Russian Academy of Sciences said on its website the quake was centered about 22 miles off the coast in the Black Sea.
The Sochi region experienced a 5.6 quake last month, RIA Novosti said.
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