The Black Sea deluge is a hypothesized prehistoric flood that occurred when the Black Sea filled rapidly circa 5600 BC. The hypothesis made headlines when The New York Times published it in December 1996.
Flood hypothesis
In 1998, William Ryan and Walter Pitman, geologists from Columbia University, published evidence that a massive flood through the Bosporus occurred about 5600 BC. Glacial meltwater had turned the Black and Caspian Seas into vast freshwater lakes, while sea levels remained lower worldwide. The freshwater lakes were emptying their waters into the Aegean Sea. As the glaciers retreated, rivers emptying into the Black Sea reduced their volume and found new outlets in the North Sea, and the water levels lowered through evaporation. Then, about 5600 BC, as sea levels rose, Ryan and Pitman suggest, the rising Mediterranean finally spilled over a rocky sill at the Bosporus. The event flooded 155,000 km2 (60,000 sq mi) of land and significantly expanded the Black Sea shoreline to the north and west. Ryan and Pitman wrote:
"Ten cubic miles [42 km3 of water poured through each day, two hundred times what flows over Niagara Falls. …The Bosporus flume roared and surged at full spate for at least three hundred days."
The review of sediments in the Black Sea in 2004 by a pan-European project (Assemblage – Noah Project) was compatible with the conclusion of Pitman and Ryan. Calculations made by Mark Siddall predicted an underwater canyon that was actually found.
Criticism
Countering the hypothesis are data collected by Ukrainian and Russian scientists, such as the research of Valentina Yanko-Hombach, a geology professor of Odessa State University, Ukraine. Her findings predate the publication of the Black Sea deluge hypothesis.
Yanko-Hombach claims that the water flow through the Bosporus repeatedly reversed direction over geological time depending on the relative water levels of the Aegean Sea and the Black Sea. This contradicts the proposed catastrophic breakage of a Bosporus sill on which Ryan and Pitman base their hypothesis. Likewise, the water levels calculated by Yanko-Hombach were different by a wide margin from those hypothesized by Ryan and Pitman.
In 2007, Yanko-Hombach, now president of the Avalon Institute of Applied Science in Winnipeg, Canada, published a scientific volume featuring 35 papers by an international group of Black Sea scientists, including her own research on this topic. The book makes available much of the earlier Russian research in English for the first time, and combines it with more recent scientific findings.
As of 2006, a cross-disciplinary research project funded by UNESCO and the International Union of Geological Sciences continued.
A report on recent research in National Geographic News in February 2009 reported that the flooding might have been "quite mild".
Archaeology
Although neolithic agriculture had by that time already reached the Pannonian plain, the authors link its spread with people displaced by the postulated flood ("Atlantis" by David Gibbins provides an entertaining fictional account of this view). More recent examinations by oceanographers such as Teofilo A. "Jun" Abrajano Jr at Rensselaer Polytechnic Institute and his Canadian colleague Ali Aksu of Memorial University of Newfoundland have cast some doubt on this catastrophic flood hypothesis. Abrajano's team, finding sapropel mud deposits in the Sea of Marmara, have concluded that there has been sustained interaction between the Mediterranean and the Black Sea for at least 10,000 years:
"For the Noah's Ark Hypothesis to be correct, one has to speculate that there was no flowing of water between the Black Sea and the Marmara Sea before the speculated great deluge. We have found this to be incorrect."
In a series of expeditions, a team of marine archeologists led by Robert Ballard identified what appeared to be ancient shorelines, freshwater snail shells, drowned river valleys, tool-worked timbers, and man-made structures in roughly 300 feet (100 m) of water off the Black Sea coast of modern Turkey. Radiocarbon dating of freshwater mollusk remains indicated an age of about 7,000 years. However, one should note that radiocarbon dating in freshwater mollusks in particular can be inaccurate.
According to a report in New Scientist magazine (4 May 2002, p. 13), the researchers found an underwater delta south of the Bosporus. There was evidence for a strong flow of fresh water out of the Black Sea in the 8th millennium BC.
The review of sediments in the Black Sea coming from a series of expeditions carried out from 1998 to 2005, firstly in the frame of a collaborative project between France (Ifremer) and Romania (GeoEcoMa), then followed by a pan-European project (Assemblage) coordinated by Gilles Lericolais, confirmed the conclusion of Pitman and Ryan. These results were also completed by the Noah project led by the Bulgarian Institute of Oceanology (IO-BAS). Furthermore, calculations made by Mark Siddall predicted an underwater canyon that was actually found. .
Other deluges
As the Ice Age retreated, other basins refilled as sea levels rose. Some refilled too slowly to be perceptible in a human life-span, such as the Aegean Basin which presents no defined sill to be breached. Others must have refilled rapidly, in cases where a sill was breached. A comparable refilling in the region of the Near East was the refilling of the flat basin of the lower Tigris-Euphrates across the Straits of Hormuz that is now occupied by the Persian Gulf and also across the Bab-el-Mandeb barrier of the Red Sea.
Other flood accounts
The proposed deluge has been connected with various Great Flood myths, notably Noah's Flood. Fundamentalist Christians claimed that "Noah's Flood was not a local flood in the Black Sea area, but a world-wide flood that has left its mark on every continent on this planet", and that the timing was wrong. On the other hand, Hershel Shanks, editor of the Biblical Archaeology Review, said that "if you want to see the Black Sea flood in Noah's flood, who's to say no?"
From http://en.wikipedia.org/
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