Ocean dynamics and anthropogenic impacts along the southern Black Sea shelf examined through the preservation of pre-modern shipwrecks

Continued exploration of the coastal area of the southern Black Sea off Sinop and Ereğli, Turkey in 2011 expanded our current understanding of the transition zone along the oxic/anoxic interface. Push cores collected with an ROV in sediments underlying the oxic, suboxic, and anoxic waters were analyzed for geochemistry, meiofauna, and microbiology to help characterize this transition zone. During the course of side-scan sonar surveys, nine shipwrecks were located in various states of preservation, all within 100–115 m depth and ranging from the 4th century B.C. to the early 20th century. Many of these wrecks have wooden components well preserved due to the influences of anoxic waters being washed up along the shelf by internal waves. However, a number of these sites have been heavily damaged by bottom trawling along the seabed up to the shelf break, highlighting the persistent threat such activities pose to submerged archaeological sites.

► We discuss the oxic/anoxic interface through the preservation state of shipwrecks. ► We present preliminary results of microbiology and meiofauna in sediment cores. ► Wreck sites are preserved at the suboxic interface but damaged by bottom trawling. ► Additional long-term monitoring of CTD and O2 at these depths is needed.