Abstract
Circular and elongated pockmarks are present between 180- and 300-m water depths in the Eastern Black Sea shelf. The circular pockmarks have diameters of 50–120 m and the elongated pockmarks are 150–200 m wide with crater depths of 10–25 m. In deeper sediments, buried pockmarks were ‘vertically stacked’, indicating that the pockmarks developed under periodically varying overpressure conditions driven by the seismologically active North Anatolian Fault. Linear elongated pockmarks were formed by downslope tensional stretching, which caused linear weak zones together with strong seafloor currents acting as a connector of circular pockmarks.
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Acknowledgements
We sincerely thank Dr. Casey Moore, Dr. Lars Zuesdorff and Dr. Janet Yun for their helpful and constructive comments in reviewing of the manuscript. We also would like to thank Dr. Zafer Y. Öner for his valuable comments on an earlier version of this paper. This research was supported by a grant (project code 100Y078) from The Scientific and Technical Research Council of Turkey (TUBITAK) and by Dokuz Eylül University Research Foundation grants (project codes 02.KB.FEN.064 and 02.KB.FEN.025).
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Çifçi, G., Dondurur, D. & Ergün, M. Deep and shallow structures of large pockmarks in the Turkish shelf, Eastern Black Sea. Geo-Mar Lett 23, 311–322 (2003). https://doi.org/10.1007/s00367-003-0138-x
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DOI: https://doi.org/10.1007/s00367-003-0138-x