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Microbiological investigations after the “Bravo” blowout (Ekofisk oil field, North Sea)


Following the accident in 1977 at an offshore oil producing platform in the Ekofisk oil field (North Sea) an estimated amount of 13000–15000 tons of oil polluted the sea. Microbiological investigations were conducted one to five weeks after the blowout and compared with data collected in the same area during the years before. Bacterial numbers in the water were fairly low. In the floating oil particles, however, extremely high values were obtained (2 × 1011 heterotrophic bacteria 1−1 and 5 × 1010 oil degrading bacteria 1−1). The data on oxygen consumption gave markedly different results indicating that the oil degradation potential of the water seemed to vary widely from one station to another. The greatest increase in oxygen consumption (following the addition of oil to the bottles) occurred in samples taken at the station where oil particles from the blowout were observed floating on the surface. This indicates a higher oil degradation potential.

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Gunkel, W., Pedersen, S., Dundas, I. et al. Microbiological investigations after the “Bravo” blowout (Ekofisk oil field, North Sea). Helgolander Meeresunters 39, 21–32 (1985).

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