Mapping The Antikythera Shipwreck
A great deal of scientific and media attention has been focused on this year's archeological study of the Antikythera Shipwreck. New technologies are providing the means to explore the ship wreck and surrounding areas to a degree never managed before. A Roman treasure ship in the year 70 BC was dashed by strong winds and heavy waves into a submerged wall off the coast of Antikythera which sank the ship. Falling off the wall and on to a ledge, the ship settled in water about 160 feet deep.Homer in the epic novel “Ulysses” talked about the winds and waves of this area.
The ship was discovered in 1900 by local sponge divers led by Captain Dimitrios Kontos. The first find was an arm of a bronze statue. These divers were using crude metal helmets and were provided air from the surface. Shortly after the first find, they started to recover other items, however the deep depth took its toll. Captain Kontos died as a result of decompression sickness and two other divers suffered paralysis which eventual lead to their deaths as well. Improvements in diving equipment and technologies led to other recovery efforts. However, these dives while safer were also limited in bottom times.
The 2013 expedition was the first to treat the wreck site as an archaeological dig. The expedition that year also started using more high tech methods.A combination Side Scan/Multibeam Sonar called the "Edgetech 4600 sonar" was designed specifically for this site. The primary purpose was to map the Antikythera coastline. Collecting data and mapping the entire Antikythera coastline up to a depth of 150 meters, the researchers were able to target the shipwreck just 100 m offshore.The information was analyzed and used as a guide of where to look during the 2014 mission that just ended.
The Exosuit has been getting top billing for its ability to send a diver to 1,000 feet for a couple of hours. The reality is that the multimillion dollar suit was used for two dives and only on the last day. While the dives did prove the concept and provide some valuable information, the amount of information it provided is small compared to the overall success. On one weekend, a yellow, torpedo-shaped vehicle made 40 passes over the entire length of the wreck site at a depth just 10 feet above the wreck. In the process it took over 50,000 images using a stereographic camera and an overlapping search pattern.The Autonomous Underwater Vehicle (AUV) was operated by researchers Dr. Oscar Pizzaro and Dr. Stefan Williams of the Australian Centre for Marine Robotics. The results were used to generate a 3d image of the research area.
Rebreathers were also a new tool this year. By using closed circuit rebreathers with mixed gas and diver propulsion vehicles to move around, the divers were able to survey with longer and safer bottom times than conventional scuba and an immensely increased range compared to traditional finning. Bottom times were extended to 30 minutes. These new tools have allowed the researchers to see the wreck and debris field as it never has before. The 3D imaging will allow the team to identify areas to search during the next expedition. The images will likely reveal items of interest for future recovery.