| CTD data, H2S water column samples and detailed bathymetric survey of the underwater Dnieper paleo-delta were analyzed to study of temporal and spatial fluctuations of oxic/anoxic interface over the gas seepage area, where methane-related microbial mats and carbonate reefs are highly developed. Time-series CTD measurements have allowed to estimate temporal variability of the isopycnal surfaces with sigma-theta (б0) values 15.4 (oxycline encased with the permanent pycnocline) and 16.2 (oxic/anoxic interface). In the investigated region quasi-periodical vertical fluctuations of the H2S-waters upper boundary (б0 = 16.2) between 130 and 165 m depths, i.e. up to 35 meters, have been observed. At the area of massive microbial reefs within this depths range a... |
