Mud volcanoes and gas Hydrates in the Black Sea - new Data From Dvurechenskii mud Volcano

METEOR cruise M52/1 revealed the presence of gas hydrates in sediments of mud volcanoes in the Sorokin Trough of the Black Sea. Methane Hydrates were sampled from Dvurechenskii MV, Odessa MV, Yalta MV, and an unnamed mud volcano. Dvurechenskii mud volcano (DMV), a flat topped "mud pie"-type structure, seems to be presently active. Pore water in the sediments of DMV is enriched in several constituents such as ammonium and chloride. These elements can only have come from deeper sediments. High sediment temperatures of up to 16.5° C in close contact to the ambient bottom water of 9° C also suggest a strong activity. Steep gradients in temperature indicate a high fluid and/or mud flux in DMV which is independently deduced by the shape of pore water profiles. Active fluid expulsion sites are also evidenced by TV-sled observation, and a potential methane flux from the sediment to the bottom water was traced by measurements.