Abyssal fan

Abyssal fan

Abyssal Fans, also known as deep-sea fans, underwater deltas, and submarine fans, are underwater structures that look like deltas formed at the end of many large rivers, such as the Nile or Mississippi Rivers. Abyssal fans are also thought of as an underwater version of alluvial fans.


Abyssal (or submarine) fans are formed due to turbidites. Turbidites are essentially gravity-driven underwater avalanches. As sediment is deposited on the continental slope, the steepest part of the ocean, it is prone to sliding down onto the continental rise due to gravity. Once the weight of the sediment accumulating gets to be too much, the pile of sediment will slide down all at once falling down onto the continental rise. After thousands of years of turbidite deposition on the rise, a fan forms towards the top of the continental rise. This fan is similar to an alluvial fan found on land near mountains and rivers. The abyssal fan has characteristics of a standard turbidite. The Bouma Sequence is used to describe the nature and sediment patterns of a turbidite.


See also

  • List of Oceanic Landforms

Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • abyssal plain —   large, relatively flat areas of ocean floor found at 5,000 6,000m below sea level. If sediments are discharged from a river and deposit relatively quickly onto the plain they may form an abyssal fan …   Geography glossary

  • Danube fan — 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… …   Wikipedia

  • submarine fan — Accumulation of land derived sediment on the seafloor; a fan is shaped like the section of a cone, with its apex at the mouth of a subbmarine canyon. The sediments consist largely of sandy material that drops from the canyon current in… …   Universalium

  • Cold seep — Marine habitats Tube worms are among the dominant species in one of four cold seep community types in the Gulf of Mexico. Littoral zone …   Wikipedia

  • Northwest Atlantic Mid-Ocean Channel — A map of the NAMOC with its major tributary IMOC.[1] The Northwest Atlantic Mid Ocean Channel (NAMOC) is the main body of a turbidity current system of channels and canyons running on the sea bottom from the Hudson Strait, through the Labrador… …   Wikipedia

  • Contourite — A contourite is a sedimentary deposit produced by thermohaline induced deepwater bottom currents and may be influenced by wind or tidal forces.[1][2] Most contourites are formed in continental rise to lower slope settings, although they may occur …   Wikipedia

  • Seabed — This article is about ocean floor. For the 2001 song by Audio Adrenaline, see Lift (Audio Adrenaline album). Map showing the underwater topography (bathymetry) of the ocean floor. Like land terrain, the ocean floor has ridges, valleys, plains and …   Wikipedia

  • Continental rise — Diagrammatic cross section of an oceanic basin The continental rise is an underwater feature found between the continental slope and the abyssal plain. This feature can be found all around the world, and it represents the final stage in the… …   Wikipedia

  • Bathymetry — Present day Earth bathymetry (and altimetry). Data from the National Geophysical Data Center s TerrainBase Digital Terrain Model. Bathymetry is the study of underwater depth of lake or ocean floors. In other words, bathymetry is the underwater… …   Wikipedia

  • Submarine canyon — A submarine canyon is a steep sided valley on the sea floor of the continental slope. Many submarine canyons are found as extensions to large rivers; however there are some that have no such association. Canyons cutting the continental slopes… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”