Black Sea Trade Project 2000

By Cheryl Ward

About 7,000 years ago, rising sea levels in the Mediterranean broke through a narrow strait that had kept the glacial runoff into the modern Black Sea basin a freshwater lake. The influx of salt water smothered the freshwater below it, and a lack of internal motion and mixing meant that no fresh oxygen reached the deep waters. They are anoxic, without oxygen, so none of the well known wood-destroying organisms can survive there.

The geological aspects of the flood are still being clarified, but W. Pittman and W. Ryan believed that it was incredibly rapid, perhaps raising the level of the lake by over 150 meters within only a few years. Other geologists suggest that a more turbid flow of up to several centuries may also be reconstructed from available evidence. In any case, it was easy to understand the enthusiasm Fred Heibert, University of Pennsylvania and INA Adjunct Professor, had for seeking ancient human settlement sites that might have been located near the edge of the ancient sea. His team's land surveys have produced evidence for Neolithic stone-workers in relatively isolated groups, and for an active Bronze Age settlement on one of Sinop's high points in addition to a rich record of farming groups from the time of Greek colonization through the medieval period.

The project brings together professionals and graduate students to examine, analyze, and interpret data and images from robots and drones far beneath the sea. In 2000, we worked west of Sinop for a total of about three weeks. An unexpected accident to our support vessel in dry dock pushed our expedition season from August to September. Early efforts concentrated on examining what Fred Heibert called the 'sweet zone'-gentle slopes that would have been somewhat elevated above the ancient lakeshore. It is on similar dry hills around Sinop that his team has found most of the archaeological sites. This area is about 80-100 m deep in the Black Sea today.

One of the first steps in any remote sensing survey is to define the search area by laying overlapping transects-long parallel lines-across the seabed with a sidescan sonar unit. The team, which included representatives from the Woods Hole Oceanographic Institute, launched a DSL 120 unit that quickly began to return a large number of anomalies, or irregularities on the seabed that cast shadows to intrigue us. Under the direction of Robert Ballard, the team selected a number of these targets to examine more closely with a remotely operated vehicle (ROV). The ROVs could send video images back to the ship along the thickly clustered wires in the umbilical cord that allowed pilots to maneuver precisely along the seabed and, we knew, within the archaeological sites there.

One of the first targets we visited was a fascinating site that includes natural and handcrafted features. The site looks as if it sits on a small ridge, and a series of rough rectangular blocks (about 40 x 20 x 6 cm) attest to human presence at an area now 90 meters below the sea. A number of wooden stakes and small logs are scattered over the site, but radiocarbon dating of these and several shaped wooden objects showed them to be less than 200 years old. Further examination and perhaps excavation at the site will clarify its ambiguous nature, but as Fred Heibert says, it is an incredible privilege simply to see this ancient landscape, sunk beneath the waves for millennia.

Even more exciting to me were the events of my first watch. I came into the 'van' where all the equipment is set up a little before midnight to serve as nautical archaeologist for the watch. It was a real thrill to approach our first target and see L'il Herc's lights suddenly illuminate a wall of amphoras standing about two meters above the seabed: the season's first shipwreck. Shipwreck A is a Byzantine period shipwreck, laden with carrot-shaped amphoras typical of Sinop and probably dating between the fourth and sixth centuries CE.

Shipwreck C is another scattered pile of transport amphoras, again, dating to the fourth to sixth centuries CE. In the Mediterranean, archaeologists have studied many amphora wrecks, but most are swathed beneath a bed of poseidon grass or other sea growth. The shipwrecks we found in the 85-95 m depths all are characterized by piles of amphoras in a mound above the seabed, but without the Mediterranean-style cloak of grass.

The last find, Shipwreck D, was identified as a target in water 320 m. Its sonar signature was a long, slender line that identified it as an upright feature of the seabed, a line that transformed itself into a wooden mast, standing about 12-14 m above the seabed. The mast is beautifully preserved, without a trace of erosion or damage. A small cavity at its tip suggests something once was attached there, probably with loops to facilitate attaching the yard. At deck level, the mast disappears into thick brown sediment topped with a fluffy, whitish organic substance biologists call "marine snow", the remains of tiny organisms that live in the water column. A number of spars, partially covered with drifted sediments, lay along the deck, some between two pairs of stanchions aft of the mast. Frame ends stick out of the sediment, and allow a rough tracing of the ship's shape and dimensions.

Quick thinking and engineering on the run allowed Martin Bowen of WHOI's Deep Submergence Lab to rig up a device to get a wood sample from the ship. Three small samples were taken from a timber that might have been a quarter rudder support. Results of radiocarbon testing suggest the wood was cut sometime between the late fourth and early sixth century, and so we had our fourth Byzantine shipwreck.

Acknowledgements

Major funding for the Black Sea project is provided by National Geographic, the I.M. Kaplan Foundation, and the Institute for Exploration. INA's participation is made possible through the generous gifts of George and Marilyn Lodge, Harry and Joan Kahn, and members of INA. Texas A&M University provided funds for C. Ward's travel to the Black Sea in 2000.