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Most Black Sea cores contained dissolved gases which expanded as the cores were brought to the surface. This caused the core sections to be separated at various points. Some cores contained sufficient gas to blow the core out the end of the barrel upon removal of the core catcher. The gases, which were sampled and analyzed on shipboard, were mostly methane with small amounts of carbon dioxide and other hydrocarbon gases. The equipment on the ship was not sensitive enough to analyze the higher hydrocarbon gases in detail so this was done at Woods Hole Oceanographic Institution. About 300 gas samples were analyzed from Holes 379, 38O/38OA, and 381. Data for the higher hydrocarbons, ethane through the pentanes are shown in

Radiolabeled products were formed from labeled substrates during anaerobic incubation of sediments from Sites 618, 619, and 622. One set of experiments formed 14 CO 2 , 14 CH 4 , and 35 SH 2 from 2-14 C-acetate and 35 S-sulfate; a second set formed 14 CH 4 from 14 C-methylamine or 14 C-trimethylamine. Levels of 14 CO 2 and 35 S 2~ formed were two to three orders of magnitude greater than 14 CH 4. Production of 14 CH 4 by Deep Sea Drilling Project (DSDP) sediments was four to five orders of magnitude less than that formed by anoxic San Francisco Bay sediment. However, incubation of Site 622 sediment slurries under H 2 demonstrated production of small quantities of CH 4. These results indicate that DSDP sediments recovered from 4 to 167 m sub-bottom (age 85,000-110,000 yr.) harbor potential microbial activity which includes sulfate reducers and methanogens. Analysis of pore waters from these DSDP sites indicates that bacterial substrates (acetate, methylated amines) were present.

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