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Local Holocene sea level changes outside the former glacial regions depended on combination of three main factors. They are general eustatic variations, tectonic (mainly seismotectonic) events and regime of sedimentation in the coastal zones. Before the last significant rise of the oceanic level, the western part of the Persian Gulf around Bahrain and Qatar was free of water. According to the Sumer legends, it was their motherland. The sea level rose to ∼20 m by the end of Vth - beginning of the IVth millennia BC.
That forced pra-Sumerians to leave and became a base for the legend of going out of Edem. The main part of the people migrated to South Mesopotamia where they mixed with tribes coming from Iran and created the Ubeid culture. At the end of the Ubeid epoch of the sea level rise, ∼3800 BC, the great 7-day storm (rains and damming of rivers by the gulf waters) produced ∼20-meter rise of the local water level and flooded the Lower Mesopotamia. It was a source of the Sumerian, Semitic and finally Bible legend about the Deluge. Among the later sea level changes, the most interesting is the regression to 2-3 m which began probably at the end of the II millennium BC and continued up to the beginning of the I millennium AD.
The Holocene sea level changes were important for Troy which was founded as a port settlement in the Scamander Gulf southward junction of the Dardanelles and the Aegean Sea. The gulf was formed by sea water flooding of the river valley. Later the river sediments began to fill the gulf. During the Trojan War (end of the II millennium BC), Troy was separated from the sea by narrow beach, but later, during the regression, the coast line moved far to the north. At the end of the regression, the sea covered a part of the continental flat and Strabo described the gulf coasts ∼3 km to the north of Troy. The further river sedimentation and tectonic uplift finally closed the gulf and Troy is situated now 5 km from the sea.
The same regression reached 5-6 m in the Black Sea where it is known as the Phanagorian regression. The 3-meter difference between the regression magnitudes in the Black Sea and Mediterranean depended probably on seismotectonic movements in the Bosporus which closed the deep flow of the Mediterranean waters to the Black Sea. The regression slowed down the surficial flow of the Black Sea waters to the Mediterranean. Probably, difference between difficult way of Argonautes and easy travel of Herodotos to the Black Sea depended on this changes.
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