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

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.

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