Out of all the flood events in history, only one can be called "the Flood."
AAPG member Walter C. Pitman III thinks he knows which one.
Pitman and co-researcher William B.F. Ryan have written a book to document their theory, Noah's Flood: The New Scientific Discoveries About the Event That Changed History, published recently by Simon & Schuster. This 352-page work describes a scientific investigation that mixes geology with oceanography, anthropology, linguistics and legend.
In short, it defines an event that may have been a turning point for civilization.
"We think it had a great effect on human history, because it widely dispersed people who had a different method of farming and had different languages," Pitman said.
Now retired as a senior research scientist for the Lamont-Doherty Earth Laboratory and adjunct professor of geology at Columbia University in New York, Pitman retains the title "special lecturer" and works at his profession five days a week.
His studies in marine magnetics, plate tectonics and eustacy are widely recognized. In 1998, the National Academy of Sciences awarded Pitman the Alexander Agassiz Medal, a prize given every three years for original contributions in oceanography.
He was cited for "his fundamental contribution to the plate tectonic revolution through insightful analysis of marine magnetic anomalies and for his studies of the causes and effects of sea level changes."
Pitman described himself as "one of many researchers" who used marine magnetics to prove and measure seafloor spreading.
"Later on, I myself used spreading-rate data to show there could have been very large changes in sea level due to changes in the mid-ocean rifts," he said.
During his career, Pitman -- a past AAPG Distinguished Lecturer -- has presented several papers at meetings sponsored by AAPG and other petroleum-related organizations, furthering the industry's understanding of eustacy, plate motion, subsidence, thermo-mechanics and the effect of sea-level changes on sequence stratigraphy.
Pitman's search for the Great Flood began more than 25 years ago. He and Ryan were working on a project with Oxford University geologist John F. Dewey, using plate tectonics to explain the deformation that had occurred in the Alpine Deformation Belt.
"Ryan was somewhat distracted, because he and Ken Shu and Maria Cita, along with other colleagues, had discovered that the Mediterranean had once dried out catastrophically," Pitman said -- and then refilled over the course of 100 years.
"Dewey jokingly said, 'Maybe that was the source of the flood myths 5.5 million years ago.' And we all laughed," he recalled, "because there were no people around at that time."
But the comment sent Pitman and Ryan into offhand speculation: Was a similar flood event, much later in history, the inspiration for stories of a Great Flood?
The Razor's Edge
In the Gilgamesh epic from Babylon, the great hero Gilgamesh seeks out the survivor of a world flood to learn the secret of eternal youth.
The Semitic tale of Noah is recounted in the book of Genesis in the Bible. God tells Noah to build an ark and fill it with two of every living creature. Then a great flood covers both hills and mountains after 40 days and 40 nights of rainfall.
Pursuing their question, Pitman and Ryan studied the Persian Gulf and the Red Sea as candidates for a catastrophic flood. But in each case, "the geology just didn't work out," Pitman said.
The Black Sea, also a possibility, was both remote and restricted. Ryan and Pitman got their first lead by studying sediment cores from the region.
"Some Woods Hole Oceanographic people had been in the Black Sea earlier and had done research work in deep water," Pitman said. "This was at a time when the Cold War was at its most chilling. The Black Sea, being owned by the Turks and the Russians, was almost off limits to expeditions."
The two quickly noticed evidence in the cores of a sudden shift from a fresh-water environment to a marine depositional environment.
"There was almost a razor-sharp edge," Pitman said.
The Woods Hole researchers theorized that the Black Sea had once been a flow-through basin -- essentially a conduit carrying fresh water into the Mediterranean Sea. A gradual mixing back of saltwater had produced the shift in environments, they thought.
"Bill Ryan and I were very skeptical," Pitman continued. "We reasoned that if an exchange had taken place, the effect on the sediments would have been very gradual. You wouldn't see this sudden change. The very precipitous change in sediments argues for a precipitous change in the Black Sea."
Seeing Is Believing
With the political situation a barrier, Pitman could do little to obtain additional information.
"Over the years, dribs and drabs of data came in," he said, "mostly from the Russian side."
Russian drilling for a proposed Istanbul subway had cut through the Bosporous, the very narrow strait connecting the Black Sea with the Sea of Marmara to the southwest.
Surprisingly, the Russians discovered very young sediments down to bedrock at a depth of 330-490 feet, or 100-130 meters, according to Pitman. These sediments appeared to be little more than 7,000 years old.
"This told us that the Bosporous had, at some time, been cut to a depth of 100 meters or more and covered with young sediments," he said.
"It argued strongly against the idea that the Black Sea had been slowly kissed by the ocean."
In another project, drilling for a bridge at the Kerch Strait between the Sea of Azov and the Black Sea, found a fresh-water river channel.
"They were able to show that there was a channel of the Don River that went right through the strait," he said. "They traced that channel down to a depth of 80 meters."
Then Russian scientists published studies of sediment cores taken during a research survey of an area near the Crimea. The studies found evidence of fine, deepwater sediments with overlapping.
Moreover, the Russians determined that much of the submerged area had been exposed at one time.
"It showed that the level of the waters had inundated this area very rapidly, that it had gone from being exposed to deep-water deposition almost instantaneously -- again, with none of the sediments that you see during a transgression," Pitman noted.
Finally, in early 1993, Pitman and Ryan were offered a chance to take part in a Russian-sponsored Black Sea expedition.
"Ryan jumped at it. I was a little hesitant, but eventually I jumped at it, too," Pitman said. "And it turned out to be a smashing success."
While the Russians looked for radio nucleides resulting from the Chernobyl reactor disaster, Ryan and Pitman searched for remnants of the Great Flood.
They surveyed east of the Crimea from off the shelf edge to on shelf, finding "up to four-meter layers of sediment that covered everything like dust," he said. "It went right down valleys and up the other side, the same sloppy, highly saturated sediments the Russians had described earlier."
A shell hash overlay hard, very compact deltaic-type sediments with mud cracks.
"These deltaic strata were truncated, so that erosion had taken place during the last glacial contact," he continued. "During the dry period the level of the Black Sea dropped, eroding the delta when wave action would have pulled up the fine sediments."
Right on top of the shell hash was evidence of the first Mediterranean invader, the mollusk Cardia Medulla, according to Pitman.
Carbon dating of the transition break placed its age at 7,550 years. Before that time, Ryan and Pitman say, the Black Sea was a fresh-water lake draining into the Mediterranean.
When the sea level rose, pressure built up on the natural dam of the Bosporous. Eventually, water began to pour into the Black Sea basin with enough force to scour out the Bosporous channel to a depth of almost 500 feet.
Water rushed in at a rate of 50 cubic kilometers a day -- about 200 times the rate of flow of Niagra Falls, Pitman said.
"It would have been a very exciting thing to see," he marveled, "from a distance."
Spreading the Word
The relentless onrush submerged an additional 140,000 square kilometers -- an area the size of Florida.
"Our guess was that it took place within a year," he said. "That was the Flood. The question is, 'Was anybody there?' And that's a difficult question because what was flooded is still flooded."
With no help from archeology available, Pitman and Ryan turned to anthropology -- specifically, the sudden appearance and spread of advanced farming methods across Europe and western Asia just after 5,500 BC.
Were the refugees in the Black Sea diaspora the ancestors of the linear band keramic, or Linear Pottery culture, that pushed agriculture across a fertile band of Europe as far as northern France?
Were they forerunners of the Dinilo Hvar farmers in the Adriatic and the Vinca people of the Hungarian plain?
Pitman and Ryan felt certain they were.
"Just before the flood there was an arid spell that lasted from about 6,200 to 5,800 BC. A number of places in Anatolia were deserted. These deserted places were immediately reoccupied after the flood," Pitman said.
"There were people who appeared along the Nile delta, using new technology and with domesticated animals. Farmers appeared in the Caucasus who practiced a special type of irrigation."
Then there were the flood legends. Could they have begun with the flooding of the Black Sea and been passed down orally for 2,500 years, before being captured in writing?
Skeptics of the Great Flood theory believe such stories might have arisen from river floods in long-populated areas to the south of the Black Sea.
Pitman disagrees.
"First, there was a warning, and you don't get any warning with a river flood," he noted. "Second, the people who packed up the ark (of Noah) packed up as if they were going away forever and weren't coming back."
More evidence could emerge next summer. Pitman said U.S. archeologists plan to conduct a dive in search of cultures whose lands were submerged in the Black Sea inundation -- which may have been the greatest flood ever witnessed by human beings.