In geology, depositional environment or sedimentary environment describes the combination of physical, chemical, and biological processes associated with the deposition of a particular type of sediment and, therefore, the rock types that will be formed after lithification, if the sediment is preserved in the rock record. In most cases, the environments associated with particular rock types or associations of rock types can be matched to existing analogues. However, the further back in geological time sediments were deposited, the more likely that direct modern analogues are not available (e.g. banded iron formations).
Diagram to show the different depositional environments in which tsunami deposits are formed – partly after Shanmugam 2006 [1]Depositional environmental model of the Araripe Basin formations, NE Brazil
Alluvial – Loose soil or sediment that is eroded and redeposited in a non-marine settingPages displaying short descriptions of redirect targets – type of Fluvial deposit. Caused by moving water in a fan shape (Alluvial Fan) and containing mostly impermeable and nonporous sediments well sorted.
Aeolian – Processes due to wind activity. Often in deserts and coastal regions and well sorted, large scale cross-beds
Fluvial – Sediment processes associated with rivers and streamsPages displaying short descriptions of redirect targets – processes due to moving water, mainly streams. Common sediments are gravel, sand, and silt.
Lacustrine – sediment deposited by a lakePages displaying wikidata descriptions as a fallback – processes due to moving water, mainly lakes. Common sediments are sand, silt, and clay.
Deltaic – Silt deposition landform at the mouth of a river (possible cross beds, ripple marks)[4] Common sediments are sand, silt, and clay.
Tide – Rise and fall of the sea level under astronomical gravitational influences – processes due to tidal currents, creates tidal flats (fine-grained, ripple marks, cross-beds).[5] Common sediments are silt and clay
Lagoonal – Shallow body of water separated from a larger one by a narrow landform. Little transportation, creates lagoon bottom environment. Common sediments are carbonates (in tropical climates).
Beach – Area of loose particles at the edge of the sea or other body of water. Caused by waves and longshore currents. Creates beaches, spits, and sandbars with the common sediments of gravel and sand.
Shallow water marine environment – processes due to waves and tidal currents, creates shelves and slopes, lagoons. Common sediments are carbonates (in tropical climates) or sand, silt, and clay (elsewhere)
Upper shoreface – Portion of the seafloor that is shallow enough to be agitated by everyday wave action
Deep water marine environment – Flat area on the deep ocean floor (abyssal plains) caused by ocean currents. Common sediments are clay, carbonate mud, silica mud.
Reef – A shoal of rock, coral or other sufficiently coherent material, lying beneath the surface of water caused by waves and tidal currents. Also creates adjacent basins. Common sediments are carbonates.
Others
Evaporite – Water-soluble mineral deposit formed by evaporation from an aqueous solution
Glacial – Persistent body of ice that is moving under its own weightPages displaying short descriptions of redirect targets
Till – angular to rounded grains, poorly sorted, unstratified (massive)
Outwash – ripple marks, cross-beds, similar to stream channel[6]
Volcanic – Rupture in a planet's crust where material escapesPages displaying short descriptions of redirect targets
Recognition of depositional environments in ancient sedimentsedit
Depositional environments in ancient sediments are recognised using a combination of sedimentary facies, facies associations, sedimentary structures and fossils, particularly trace fossil assemblages, as they indicate the environment in which they lived.
Referencesedit
^Shanmugam G. (2006). "The Tsunamite Problem". Journal of Sedimentary Research. 6 (5): 718–730. Bibcode:2006JSedR..76..718S. doi:10.2110/jsr.2006.073.
^"Basics—Table of Depositional Environments". commons.wvc.edu. Retrieved 2020-01-13.
^ abcEarle, Steven (September 2015). "6.3 Depositional Environments and Sedimentary Basins – Physical Geology". Physical Geology. Retrieved 2020-01-13.
^"Basics—Table of Depositional Environments". commons.wvc.edu. Retrieved 2020-01-13.
^"Basics—Table of Depositional Environments". commons.wvc.edu. Retrieved 2020-01-13.
^"Basics—Table of Depositional Environments". commons.wvc.edu. Retrieved 2020-01-13.
Harold G. Reading. 1996. Sedimentary Environments: Processes, Facies and Stratigraphy. Blackwell Publishing Limited.
External linksedit
Depositional environments on e-notes
February 16, 2024
depositional, environment, geology, depositional, environment, sedimentary, environment, describes, combination, physical, chemical, biological, processes, associated, with, deposition, particular, type, sediment, therefore, rock, types, that, will, formed, af. In geology depositional environment or sedimentary environment describes the combination of physical chemical and biological processes associated with the deposition of a particular type of sediment and therefore the rock types that will be formed after lithification if the sediment is preserved in the rock record In most cases the environments associated with particular rock types or associations of rock types can be matched to existing analogues However the further back in geological time sediments were deposited the more likely that direct modern analogues are not available e g banded iron formations A diagram of various depositional environments Contents 1 Types of depositional environments 2 Recognition of depositional environments in ancient sediments 3 References 4 External linksTypes of depositional environments edit nbsp Diagram to show the different depositional environments in which tsunami deposits are formed partly after Shanmugam 2006 1 nbsp Depositional environmental model of the Araripe Basin formations NE BrazilContinental 2 3 Alluvial Loose soil or sediment that is eroded and redeposited in a non marine settingPages displaying short descriptions of redirect targets type of Fluvial deposit Caused by moving water in a fan shape Alluvial Fan and containing mostly impermeable and nonporous sediments well sorted Aeolian Processes due to wind activity Often in deserts and coastal regions and well sorted large scale cross beds Fluvial Sediment processes associated with rivers and streamsPages displaying short descriptions of redirect targets processes due to moving water mainly streams Common sediments are gravel sand and silt Lacustrine sediment deposited by a lakePages displaying wikidata descriptions as a fallback processes due to moving water mainly lakes Common sediments are sand silt and clay Transitional 3 Deltaic Silt deposition landform at the mouth of a river possible cross beds ripple marks 4 Common sediments are sand silt and clay Tide Rise and fall of the sea level under astronomical gravitational influences processes due to tidal currents creates tidal flats fine grained ripple marks cross beds 5 Common sediments are silt and clay Lagoonal Shallow body of water separated from a larger one by a narrow landform Little transportation creates lagoon bottom environment Common sediments are carbonates in tropical climates Beach Area of loose particles at the edge of the sea or other body of water Caused by waves and longshore currents Creates beaches spits and sandbars with the common sediments of gravel and sand Lake Large body of relatively still waterMarine 3 Shallow water marine environment processes due to waves and tidal currents creates shelves and slopes lagoons Common sediments are carbonates in tropical climates or sand silt and clay elsewhere Upper shoreface Portion of the seafloor that is shallow enough to be agitated by everyday wave action Lower shoreface Part of the seafloor undisturbed by waves Deep water marine environment Flat area on the deep ocean floor abyssal plains caused by ocean currents Common sediments are clay carbonate mud silica mud Reef A shoal of rock coral or other sufficiently coherent material lying beneath the surface of water caused by waves and tidal currents Also creates adjacent basins Common sediments are carbonates Others Evaporite Water soluble mineral deposit formed by evaporation from an aqueous solution Glacial Persistent body of ice that is moving under its own weightPages displaying short descriptions of redirect targets Till angular to rounded grains poorly sorted unstratified massive Outwash ripple marks cross beds similar to stream channel 6 Volcanic Rupture in a planet s crust where material escapesPages displaying short descriptions of redirect targets Tsunami Sedimentary unit deposited by a tsunamiRecognition of depositional environments in ancient sediments editDepositional environments in ancient sediments are recognised using a combination of sedimentary facies facies associations sedimentary structures and fossils particularly trace fossil assemblages as they indicate the environment in which they lived References edit Shanmugam G 2006 The Tsunamite Problem Journal of Sedimentary Research 6 5 718 730 Bibcode 2006JSedR 76 718S doi 10 2110 jsr 2006 073 Basics Table of Depositional Environments commons wvc edu Retrieved 2020 01 13 a b c Earle Steven September 2015 6 3 Depositional Environments and Sedimentary Basins Physical Geology Physical Geology Retrieved 2020 01 13 Basics Table of Depositional Environments commons wvc edu Retrieved 2020 01 13 Basics Table of Depositional Environments commons wvc edu Retrieved 2020 01 13 Basics Table of Depositional Environments commons wvc edu Retrieved 2020 01 13 Harold G Reading 1996 Sedimentary Environments Processes Facies and Stratigraphy Blackwell Publishing Limited External links editSedimentary Environments Classification Charts Depositional environments on e notes Retrieved from https en wikipedia org w index php title Depositional environment amp oldid 1166830255, wikipedia, wiki, book, books, library,
