Abyssal fans, also known as deep-sea fans, underwater deltas, and submarine fans, are underwater geological structures associated with large-scale sediment deposition and formed by turbidity currents. They can be thought of as an underwater version of alluvial fans and can vary dramatically in size, with widths from several kilometres to several thousands of kilometres[1] The largest is the Bengal Fan, followed by the Indus Fan, but major fans are also found at the outlet of the Amazon, Congo, Mississippi and elsewhere.[2][3][4]
Distribution of detritus in a depositional system.
Abyssal (or submarine) fans are formed from turbidity currents.
These currents begin when a geologic activity pushes sediments over the edge of a continental shelf and down the continental slope, creating an underwater landslide. A dense slurry of muds and sands speeds towards the foot of the slope, until the current slows. The decreasing current, having a reduced ability to transport sediments, deposits the grains it carries, thus creating a submarine fan. The slurry continues to slow as it is moved towards the continental rise until it reaches the ocean bed. Thus results a series of graded sediments of sand, silt and mud, which are known as turbidites, as described by the Bouma sequence.
^Gluyas, J. & Swarbrick, R. (2004) Petroleum Geoscience. Publ. Blackwell Publishing
^Clift; Gaedicke; Edwards; Lee; Hildebrand; Amjad; White & Schlüter (2002). "The stratigraphic evolution of the Indus Fan and the history of sedimentation in the Arabian Sea". Marine Geophysical Researches. 23 (3): 223–245. doi:10.1023/A:1023627123093. S2CID 129735252.
^Covault, J.A. (2011). "Submarine Fans and Canyon-Channel Systems: A Review of Processes, Products, and Models". Nature Education Knowledge. 3 (10): 4.
^Shanmugam, G. (2016). "Submarine fans: A critical retrospective (1950–2015)". Journal of Palaeogeography. 5 (2): 110–184. doi:10.1016/j.jop.2015.08.011.
Sources
"Turbidites Hold Great Potential for Deepwater Exploration" (PDF). Baker Hughes, Inc. 2000.[permanent dead link]
Svetlana Kostic; Gary Parker (2004). (PDF). Archived from the original (PDF) on 2008-08-20. Retrieved 2009-09-17.
Allen, Philip & Allen, John, 2005. Basin Analysis: Principles and Applications. 2nd ed. Blackwell.
March 08, 2023
abyssal, also, known, deep, fans, underwater, deltas, submarine, fans, underwater, geological, structures, associated, with, large, scale, sediment, deposition, formed, turbidity, currents, they, thought, underwater, version, alluvial, fans, vary, dramatically. Abyssal fans also known as deep sea fans underwater deltas and submarine fans are underwater geological structures associated with large scale sediment deposition and formed by turbidity currents They can be thought of as an underwater version of alluvial fans and can vary dramatically in size with widths from several kilometres to several thousands of kilometres 1 The largest is the Bengal Fan followed by the Indus Fan but major fans are also found at the outlet of the Amazon Congo Mississippi and elsewhere 2 3 4 Distribution of detritus in a depositional system Contents 1 Formation 2 See also 3 References 4 SourcesFormation EditThis section does not cite any sources Please help improve this section by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Abyssal fan news newspapers books scholar JSTOR December 2022 Learn how and when to remove this template message Abyssal or submarine fans are formed from turbidity currents These currents begin when a geologic activity pushes sediments over the edge of a continental shelf and down the continental slope creating an underwater landslide A dense slurry of muds and sands speeds towards the foot of the slope until the current slows The decreasing current having a reduced ability to transport sediments deposits the grains it carries thus creating a submarine fan The slurry continues to slow as it is moved towards the continental rise until it reaches the ocean bed Thus results a series of graded sediments of sand silt and mud which are known as turbidites as described by the Bouma sequence See also EditList of oceanic landformsReferences Edit Gluyas J amp Swarbrick R 2004 Petroleum Geoscience Publ Blackwell Publishing Clift Gaedicke Edwards Lee Hildebrand Amjad White amp Schluter 2002 The stratigraphic evolution of the Indus Fan and the history of sedimentation in the Arabian Sea Marine Geophysical Researches 23 3 223 245 doi 10 1023 A 1023627123093 S2CID 129735252 Covault J A 2011 Submarine Fans and Canyon Channel Systems A Review of Processes Products and Models Nature Education Knowledge 3 10 4 Shanmugam G 2016 Submarine fans A critical retrospective 1950 2015 Journal of Palaeogeography 5 2 110 184 doi 10 1016 j jop 2015 08 011 Sources Edit Turbidites Hold Great Potential for Deepwater Exploration PDF Baker Hughes Inc 2000 permanent dead link Svetlana Kostic Gary Parker 2004 The Response of Turbidity Currents to a Canyon Fan Transition Internal Hydraulic Jumps and Depositional Signatures PDF Archived from the original PDF on 2008 08 20 Retrieved 2009 09 17 Allen Philip amp Allen John 2005 Basin Analysis Principles and Applications 2nd ed Blackwell Retrieved from https en wikipedia org w index php title Abyssal fan amp oldid 1131325262, wikipedia, wiki, book, books, library,
