The paper presents the preliminary results about the distribution of dissolved methane in water of Bransfield strait deep sea (more 1000 m) area by gas chromatography. The gasogeochemical survey revealed single methane seepage at 1397 meters with high methane concentration (43 nmol/l) in the bottom water horizon. Also, it was discovered that methane saturated (10,29-14,46 nmol/l) water layer covered the space about 30-35 km around the central cite of methane anomaly. The studies of geomicrobiological parameters of sea water revealed the rich microbiological filter in the methane discharge zone. The thermogenic origin of methane was confirmed by the discovery of cultivated forms of thermophilic methanotrophic bacteria founded in the microbiological filter.

Polonik Nikita Sergeevich, Candidate of Sciences (Chemistry), Research Scientist, Laboratory of Gas Geochemistry, V. I. Il'ichev Pacific Oceanological Institute FEB RAS, 43, Baltiyskaya st., Vladivostok, 690041, Russian Federation, e-mail: nikpol@poi.dvo.ru 

Ponomareva Anna Leonidovna, Candidate of Sciences (Biology), Senior Research Scientist, Laboratory a Comprehensive Study of Environment and Mineral Resources, V. I. Il'ichev Pacific Oceanological Institute FEB RAS, 43, Baltiyskaya st., Vladivostok, 690041, Russian Federation, e-mail: giston@list.ru 

Shakirov Renat Belalovich, Doctor of Sciences (Geology and Mineralogy), Head, Laboratory of Gas Geochemistry, V. I. Il'ichev Pacific Oceanological Institute FEB RAS, 43, Baltiyskaya st., Vladivostok, 690041, Russian Federation, e-mail: ren@poi.dvo.ru

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