Active Slumping Offshore Amasra (Southwest Black Sea) and Its Relation With Regional Tectonics

Yıl 2004, Cilt: 128 Sayı: 128, 27 - 47, 01.09.2004

İsmail Kuşçu Jeffrey R. Parke Robert S. Whıte Dan Mckenzıe Gareth A. Anderson Timothy A. Mınshull Naci Görür A.m.celal Şengör

Öz

The Bartın earthquake of 3rd September, 1968 provided the first evidence for active thrust faulting at the southern margin of the Black Sea. 500 km of 2D seismic reflection profiles acquired in this area show thepresence of large scale slumps and landslips due to oversteepening of the shelf sediments, as a result of thrust faulting. The onshore drainage pattern is affected by interaction of the faulting with the geology, and this in turn affects the offshore shelf. Kilometre-scale bathymetric features on the sea-floor indicate a previous mass movement of a relatively coherent block of sediment, which has subsequently been partially buried. The source location for the block is visible on the geological map of the area. Incisional and erosional features in Pliocene sediments far from today's coastline and drainage systems suggest that water level was lower at the time they were formed than at present day.

Anahtar Kelimeler

The Black Sea, seismicity, seismic reflection study, slumping

Kaynakça

• Albers, J. P. and Kalafatçıoğlu, A. 1969. Bartın- Amasra earthquake, Turkey, Sept. 3, 1968. United States Geological Survey Project report (IR) TU-5.
• Alptekin, Ö., 1973. Focal mechanism of earthquakes in western Turkey and their tectonic implications. PhD thesis, New Mexico Institute of Mining and Technology, USA.
• ; Nabelek, J. L. and Toksöz, M. N. 1986. Source mechanism of the Bartın earthquake of September 3, 1968 in north-western Turkey: Evidence for active thrust faulting at the southern Black Sea margin. Tectono- physics, 122, 73-88.
• Carlson, P., 1978. Holocene slump on the continental shelf off Malaspina Glacier, Gulf of Alaska. Bulletin of American Association of Petro- leum Geologist, 62, 2412. Chamberlain, J.; Sader, J.; Landman, K. and White.L. 2001., Incipient plane-strain failure of a rectangular block under gravity. International Journal of Mechanical Science, 43, 793-815. Chuang, F. and Greeley, R., 2000. Large mass move- ments on Callisto. Journal of Geophysical Research - Planets, 105. 20, 227-20, 244.
• Dade, W. and Huppert, H., 1998. Long-runout rockfalls. Geology, 26, 803-806.
• Dewey, J. W., 1976. Seismicity of northern Anatolia. Bulletin of Seismological Society of America, 3, 843-868. Dingle, R., 1977. The anatomy of a large submarine slump on a sheared continental margin (southeast Africa). Journal of the Geological Society, 134, 293. Dunne, W. and Ferrill, D., 1988. Blind thrust systems. Geology, 16, 33-36.
• Ergünay, O. and Tabban, A., 1983. Isoseismal map of the Bartın earthquake based on the official damage statistics of the General Directorate of Disaster Affair of the Government of Turkey. Unpublished documents and map. Erinç, S., 1984. Karadeniz çanağının jeomorfolojik ve yapısal özelliklerinin morfometrisi. İstanbul Universitesi Deniz Bilimleri ve Coğrafya Enstitüsü Bülteni, 1, 15-22.
• Goldsworthy, M. and Jackson, J., 2000. Active normal faulting in Greece by geomorphological and drainage patterns. Journal of the Geological Society, 157,967-981.
• Görür, N., 1997. Cretaceous syn- to post-rift sedimantation on the continental margin of the western Black Sea. In: Robinson, A. (ed). Regional and petroleum geology of the Black Sea and surrounding region. American Association of Petroleum Geologist Memoir, American Association of Petroleum Geolo- gist yayını, 68, 227-240.
• Hampton, M. and Lee, H., 1996. Submarine landslides. Review of Geophysics, 34, 33-59.
• Hazlett, R.; Buesch, D.; Anderson, J.; Elan, R. and Scandone, R., 1991. Geology, failure conditions, and implications of seismogenic avalanches of the 1944 eruption at Vesuvius, Italy. Journal of Volcanology and Geothermal Research, 47, 249-264.
• Jackson, J., 1980. Reactivation of basement faults and crystal shortening in orogenic belts. Nature, 283, 343-346. and McKenzie, D., 1984. Active tectonics of the Alpine - Himalayan belt between western Turkey and Pakistan. Geophysical Journal of the Royal Astronomical Society, 77. 185-264.
• Ketin, İ., 1966. Tectonic units of Anatolia. Bulletin of General Directorate of Mineral Research and Exploration , 66, 24-33.
• and Abdüsselamoğlu, S., 1969. Bartın depreminin etkileri. Bulletin of Geological Society of Turkey, 12, sayı 1-2, 66-76.
• Kudo, K.1983. Seismic source characteristics of recent major earthquakes in Turkey. In: Ohta, Y. (ed). A comprehensive study on earthquake disasters in Turkey in view of seismic risk reduction. Hokkaido University publication.
• Landers, J. F., 1969. Seismological notes - September and October 1968. Seismological Society of America, 59, 1023-1030.
• Letouzey, J.; Bijou-Duval, B.; Dorkel, A.;Gon- nard,R.,Lristchev,K.;Montadert, L, and Sun- gurlu,O.;1977.The Black Sea-A marginal basin,geophysical and geologic data ln:Bijou, Duval B.and Montadert,L.(eds). International Symposiumonthe structural History of the Mediter ranean Basins. Editions Technip, Paris, 363-376.
• McKenzie, D., 1972. Active tectonics of the Mediterranean region. Geophysical Journal of the Astronomical Society. 30, 109-185..;
• Okay, A. İ.; Şengör, A. M. C. and Görür, N., 1994. Kinematic history of the opening of the Black Sea and its effect on the surrounding regions. Geology, 22, 267-270.
• Robinson, A.; Spadini, G. and Rudat, J., 1995. Stratigraphic evolution of the Black Sea: inferences from basin modeling. Marine and Petroleum Geology, 12, 821-835.
• Ross, D., 1971. Mass physical properties and slope stability of sediments of the northern Middle America trench. Journal of Geophysical Research, 76, 704.
• Ryan, W.; Pitman, W.; Major, C.; Shimkus, K.; Moskalenko, V.; Jones, G.; Dimitrov, P.; Görür, N.; Sakınç, M. and Yüce, H., 1997. An abrupt drowning of the Black Sea shelf. Marine Geology, 138, 119-126.
• Soysal, H. Sipahioğlu, S. Kolçak, D. and Altınok. Y. 1981. Türkiye ve çevresinin tarihsel deprem kataloğu. Teknik rapor, Türkiye Bilimsel ve Teknik Araştırma Kurumu proje no: TBAG 341.
• Spadini, G.; Robinson, A. and Cloetingh, S., 1996. Western versus eastern Black Sea tectonic evolution: pre-rift lithospheric controls on basin formation. Tectonophysics, 266, 139- 154.
• Stoffers, P.; Degens, E. and Trimonis, E. 1978. Stratigraphy and suggested ages of Black Sea sediments. Initial report, Deep Sea Drilling Project, 42, 483-487.
• Şengör, A. M. C., 1979. The North Anatolian trans- form fault: its age, offset and tectonic significance. Journal of Geological Society of London, 136, 269-282.
• ; Yılmaz, Y. and Ketin, İ., 1980. Remnants of pre-Late Jurassic ocean in northern Turkey: fragments of Permian - Triassic Paleo- Tethys. Geological Society of America Bulletin, 91 (part I), 499-609.
• and Canıtez, N., 1982. The North Anatolian fault. In: Berchemer and K. Hsu (eds.). Alpine and Mediterranean Geodynamics. Geodynamical Series, American Geophys- ical Union, 7, 205-216.
• Şengör.A.M.C.; Büyükaşıkoğlu, S. and Canıtez, N., 1983. Neotectonics of the Pontides: implications for the "incompatible" structures along the North Anatolian fault. Journal of Structural Geology, 5, 211 -216.
• ; Görür, N. and Şaroğlu, F., 1985. Strike-slip faulting and related basin formation in zones of tectonic escape: Turkey as a case study. In: K. T. Biddle, N. C. Blick (eds). Strike-slip Deformation, Basin Formation and Sedimen- tation. Economical Paleontology and Miner- alogy Special Publication, 37. 227-264.
• Tokay, M., 1964. Türkiye Jeoloji Haritası, Zonguldak paftası (1/500.000). Maden Tetkik ve Arama Genel Müdürlüğü (MTA), Ankara.