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ContentsContents

IntroductionIntroduction Unconsolidated clastic sedimentsUnconsolidated clastic sediments Sedimentary rocksSedimentary rocks DiagenesisDiagenesis Sediment transport and depositionSediment transport and deposition Sedimentary structuresSedimentary structures Facies and depositional Facies and depositional

environmentsenvironments Glacial/eolian/lacustrine Glacial/eolian/lacustrine

environmentsenvironments Fluvial/deltaic/coastal Fluvial/deltaic/coastal

environmentsenvironments Shallow/deep marine Shallow/deep marine

environmentsenvironments

Stratigraphic principlesStratigraphic principles Sequence stratigraphySequence stratigraphy Sedimentary basinsSedimentary basins Models in sedimentary Models in sedimentary

geologygeology Applied sedimentary Applied sedimentary

geologygeology ReflectionReflection

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Sedimentary basinsSedimentary basins

• Sedimentary basins are the subsiding areas where Sedimentary basins are the subsiding areas where sediments accumulate to form stratigraphic successionssediments accumulate to form stratigraphic successions

• The tectonic setting is the premier criterion to distinguish The tectonic setting is the premier criterion to distinguish different types of sedimentary basinsdifferent types of sedimentary basins

• Extensional basinsExtensional basins occur within or between plates and are occur within or between plates and are associated with increased heat flow due to hot mantle plumesassociated with increased heat flow due to hot mantle plumes

• Collisional basinsCollisional basins occur where plates collide, either occur where plates collide, either characterized by subduction of an oceanic plate or continental characterized by subduction of an oceanic plate or continental collisioncollision

• Transtensional basinsTranstensional basins occur where plates move in a strike- occur where plates move in a strike-slip fashion relative to each otherslip fashion relative to each other

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Sedimentary basinsSedimentary basins

ExtensionExtension

• Rift basinsRift basins develop in continental crust and constitute the develop in continental crust and constitute the incipient extensional basin type; if the process continues it incipient extensional basin type; if the process continues it will ultimately lead to the development of an will ultimately lead to the development of an ocean basinocean basin flanked by flanked by passive marginspassive margins, alternatively an , alternatively an intracratonic basinintracratonic basin will form will form

• Rift basins consist of a graben or half-graben separated Rift basins consist of a graben or half-graben separated from surrounding horsts by normal faults; they can be filled from surrounding horsts by normal faults; they can be filled with both continental and marine depositswith both continental and marine deposits

• Intracratonic basins develop when rifting ceases, which Intracratonic basins develop when rifting ceases, which leads to lithospheric cooling due to reduced heat flow; they leads to lithospheric cooling due to reduced heat flow; they are commonly large but not very deepare commonly large but not very deep

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Sedimentary basinsSedimentary basins

ExtensionExtension

• Rift basinsRift basins develop in continental crust and constitute the develop in continental crust and constitute the incipient extensional basin type; if the process continues it incipient extensional basin type; if the process continues it will ultimately lead to the development of an will ultimately lead to the development of an ocean basinocean basin flanked by flanked by passive marginspassive margins, alternatively an , alternatively an intracratonic basinintracratonic basin will form will form

• Rift basins consist of a graben or half-graben separated Rift basins consist of a graben or half-graben separated from surrounding horsts by normal faults; they can be filled from surrounding horsts by normal faults; they can be filled with both continental and marine depositswith both continental and marine deposits

• Intracratonic basins develop when rifting ceases, which Intracratonic basins develop when rifting ceases, which leads to lithospheric cooling due to reduced heat flow; they leads to lithospheric cooling due to reduced heat flow; they are commonly large but not very deepare commonly large but not very deep

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Sedimentary basinsSedimentary basins

ExtensionExtension

• Proto-oceanic troughs form the transitional stage to the Proto-oceanic troughs form the transitional stage to the development of large ocean basins, and are underlain by development of large ocean basins, and are underlain by incipient oceanic crustincipient oceanic crust

• Passive margins develop on continental margins along the Passive margins develop on continental margins along the edges of ocean basins; subsidence is caused by lithospheric edges of ocean basins; subsidence is caused by lithospheric cooling and sediment loading, and depending on the cooling and sediment loading, and depending on the environmental setting clastic or carbonate facies may environmental setting clastic or carbonate facies may dominatedominate

• Ocean basins are dominated by pelagic deposition Ocean basins are dominated by pelagic deposition (biogenic material and clays) in the central parts and (biogenic material and clays) in the central parts and turbidites along the marginsturbidites along the margins

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Sedimentary basinsSedimentary basins

CollisionCollision

• Subduction is a common process at active margins where Subduction is a common process at active margins where plates collide and at least one oceanic plate is involved; plates collide and at least one oceanic plate is involved; several types of sedimentary basins can be formed due to several types of sedimentary basins can be formed due to subduction, including subduction, including trench basinstrench basins, , forearc basinsforearc basins, , backarc basinsbackarc basins, and , and retroarc foreland basinsretroarc foreland basins

• Trench basins can be very deep, and the sedimentary fill Trench basins can be very deep, and the sedimentary fill depends primarily on whether they are intra-oceanic or depends primarily on whether they are intra-oceanic or proximal to a continentproximal to a continent

• Accretionary prisms are ocean sediments that are scraped Accretionary prisms are ocean sediments that are scraped off the subducting plate; they sometimes form island chainsoff the subducting plate; they sometimes form island chains

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Sedimentary basinsSedimentary basins

CollisionCollision

• Forearc basins form between the accretionary prism and Forearc basins form between the accretionary prism and the volcanic arc and subside entirely due to sediment the volcanic arc and subside entirely due to sediment loading; like trench basins, their fill depends strongly on loading; like trench basins, their fill depends strongly on whether they are intra-oceanic or proximal to a continentwhether they are intra-oceanic or proximal to a continent

• Backarc basins are extensional basins that may form on the Backarc basins are extensional basins that may form on the overriding plate, behind the volcanic arcoverriding plate, behind the volcanic arc

• Retroarc foreland basins form as a result of lithospheric Retroarc foreland basins form as a result of lithospheric loading behind a mountainous arc under a compressional loading behind a mountainous arc under a compressional regime; they are commonly filled with continental depositsregime; they are commonly filled with continental deposits

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Sedimentary basinsSedimentary basins

CollisionCollision

• Continental collision leads to the creation of orogenic Continental collision leads to the creation of orogenic (mountain) belts; lithospheric loading causes the (mountain) belts; lithospheric loading causes the development of development of peripheral foreland basinsperipheral foreland basins, which , which typically exhibit a fill from deep marine through shallow typically exhibit a fill from deep marine through shallow marine to continental depositsmarine to continental deposits

• Foreland basins can accumulate exceptionally thick (~10 Foreland basins can accumulate exceptionally thick (~10 km) stratigraphic successionskm) stratigraphic successions

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Sedimentary basinsSedimentary basins

TranstensionTranstension

• Strike-slip basinsStrike-slip basins form in transtensional regimes and are form in transtensional regimes and are usually relatively small but also deep; they are commonly usually relatively small but also deep; they are commonly filled with coarse facies (e.g., alluvial fans) adjacent to filled with coarse facies (e.g., alluvial fans) adjacent to lacustrine or marine depositslacustrine or marine deposits

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