Danube fan

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The Danube fan is a relict[clarification needed] sedimentary feature in the northwestern part of the bottom of the Black Sea. It crosses three of its four major physiographic provinces: basin slope, basin apron, and the Euxine abyssal plain) and splits the abyssal plain into two inequal parts.[1]

The fan was deposited by the Danube (mostly), Dniester, Southern Bug, and Dnieper rivers. It extends from the shelf break zone an approximately 200m isobath[2] for about 150 km downslope and reaches the depth of about 2,200 m within the abyssal plain.[3]

The fan is a relict from Pleistocene times when the sea level was lower, and at present, little fluvial sediment is being added to the fan; most of material is deposited in the river estuaries.[4]

The Danube sediment supply is via the Danube Canyon (also called Viteaz Canyon).[3]

References[edit]

  1. ^ Chapter: "Bathymetry and Microtopography of Black Sea: Structure" of the 20th Memoir The Black Sea — Geology, Chemistry, and Biology of the American Association of Petroleum Geologists (1974)
  2. ^ "Environmental Degradation of the Black Sea: Challenges and Remedies", editors Șükrü T. Beșiktepe, Ümit Ünlüata, Alexandru S. Bologa, 1999, ISBN 0792356764 p.40
  3. ^ a b "Late Quaternary channel avulsions on the Danube deep-sea fan, Black Sea", Marine Geology, September 2001; 179(1-2) : 25-37
  4. ^ Ross, D. A., E. T. Degens, and J. MacIlvaine (1970) "Black Sea: recent sedimentary history", Science, vol. 170, no. 3954, p. 163-165