fbpx
Wikipedia

Western Interior Seaway

December 08, 2023

The Western Interior Seaway (also called the Cretaceous Seaway, the Niobraran Sea, the North American Inland Sea, and the Western Interior Sea) was a large inland sea that split the continent of North America into two landmasses. The ancient sea, which existed from the early Late Cretaceous (100 million years ago) to the earliest Paleocene (66 Ma), connected the Gulf of Mexico, through the United States and Canada, to the Arctic Ocean. The two land masses it created were Laramidia to the west and Appalachia to the east. At its largest extent, it was 2,500 feet (760 m) deep, 600 miles (970 km) wide and over 2,000 miles (3,200 km) long.

Map of North America with the Western Interior Seaway during the Campanian

Origin and geology edit

 
A broken concretion with fossils inside; late Cretaceous Pierre Shale near Ekalaka, Montana.
 
Monument Rocks (Kansas), located 25 miles south of Oakley.

By Late-Cretaceous times, Eurasia and the Americas had separated along the south Atlantic, and subduction on the west coast of the Americas had commenced, resulting in the Laramide orogeny, the early phase of growth of the modern Rocky Mountains. The Western Interior Seaway may be seen as a downwarping of the continental crust ahead of the growing Laramide/Rockies mountain chain.[1]

The earliest phase of the Seaway began in the mid-Cretaceous period when an arm of the Arctic Ocean transgressed south over western North America; this formed the Mowry Sea, so named for the Mowry Shale, an organic-rich rock formation.[1] In the south, the Gulf of Mexico was originally an extension of the Tethys Sea. In time, the southern embayment merged with the Mowry Sea in the late Cretaceous, forming the "complete" Seaway, creating isolated environments for land animals and plants.[1]

Relative sea levels fell multiple times, as a margin of land temporarily rose above the water along the ancestral Transcontinental Arch,[2] each time rejoining the separated, divergent land populations, allowing a temporary mixing of newer species before again separating the populations.

At its largest, the Western Interior Seaway stretched from the Rockies east to the Appalachians, some 1,000 km (620 mi) wide. At its deepest, it may have been only 800 or 900 metres (2,600 or 3,000 ft) deep, shallow in terms of seas. Two great continental watersheds drained into it from east and west, diluting its waters and bringing resources in eroded silt that formed shifting delta systems along its low-lying coasts. There was little sedimentation on the eastern shores of the Seaway; the western boundary, however, consisted of a thick clastic wedge eroded eastward from the Sevier orogenic belt.[1][3] The western shore was thus highly variable, depending on variations in sea level and sediment supply.[1]

Widespread carbonate deposition suggests that the Seaway was warm and tropical, with abundant calcareous planktonic algae.[4] Remnants of these deposits are found in northwest Kansas. A prominent example is Monument Rocks, an exposed chalk formation towering 70 feet (21 m) over the surrounding range land. It is designated a National Natural Landmark and one of the Eight Wonders of Kansas. It is located 25 miles (40 km) south of Oakley, Kansas.[5] The Western Interior Seaway is believed to have behaved similarly to a giant estuary in terms of water mass transport. Riverine inputs exited the seaway as coastal jets, while correspondingly drawing in Tethyan waters from the south and Boreal waters from the north.[6] During the late Cretaceous, the Western Interior Seaway went through multiple periods of anoxia, when the bottom water was devoid of oxygen and the water column was stratified.[7]

At the end of the Cretaceous, continued Laramide uplift hoisted the sandbanks (sandstone) and muddy brackish lagoons (shale), thick sequences of silt and sandstone still seen today as the Laramie Formation, while low-lying basins between them gradually subsided. The Western Interior Seaway divided across the Dakotas and retreated south towards the Gulf of Mexico. This shrunken, and final regressive phase is sometimes called the Pierre Seaway.[1]

During the early Paleocene, parts of the Western Interior Seaway still occupied areas of the Mississippi Embayment, submerging the site of present-day Memphis. Later transgression, however, was associated with the Cenozoic Tejas sequence, rather than with the previous event responsible for the Seaway.[8][9][10]

Fauna edit

The Western Interior Seaway was a shallow sea, filled with abundant marine life. Interior Seaway denizens included predatory marine reptiles such as plesiosaurs, and mosasaurs. Other marine life included sharks such as Squalicorax, Cretoxyrhina, and the giant shellfish-eating Ptychodus mortoni (believed to be 10 metres (33 ft) long);[11] and advanced bony fish including Pachyrhizodus,[12] Enchodus, and the massive 5-metre (16 ft) long Xiphactinus, larger than any modern bony fish.[13] Other sea life included invertebrates such as mollusks, ammonites, squid-like belemnites, and plankton including coccolithophores that secreted the chalky platelets that give the Cretaceous its name, foraminiferans and radiolarians.[14][15]

The Western Interior Seaway was home to early birds, including the flightless Hesperornis that had stout legs for swimming through water and tiny wings used for marine steering rather than flight; and the tern-like Ichthyornis, an early avian with a toothy beak. Ichthyornis shared the sky with large pterosaurs such as Nyctosaurus and Pteranodon. Pteranodon fossils are very common; it was probably a major participant in the surface ecosystem, though it was found in only the southern reaches of the Seaway.[16]

Inoceramids (oyster-like bivalve molluscs) were well-adapted to life in the oxygen-poor bottom mud of the seaway.[17] These left abundant fossils in the Kiowa, Greenhorn, Niobrara, Mancos, and Pierre formations. There is great variety in the shells and the many distinct species have been dated and can be used to identify specific beds in those rock formations of the seaway. Many species can easily fit in the palm of the hand, while some like Inoceramus (Haploscapha) grandis[18] could be well over a meter in diameter. Entire schools of fish sometimes sought shelter within the shell of the giant Platyceramus.[19] The shells of the genus are known for being composed of prismatic calcitic crystals that grew perpendicular to the surface, and fossils often retain a pearly luster.[20]

See also edit

References edit

  1. ^ a b c d e f Stanley, Steven M. (1999). Earth System History. New York: W.H. Freeman and Company. pp. 487–489. ISBN 0-7167-2882-6.
  2. ^ R.J. Weimer (1984). J.S. Schlee (ed.). "Relation of unconformities, tectonics, and sea-level changes, Cretaceous of Western Interior, U.S.A.; in" (PDF). AAPG Memoir. American Association of Petroleum Geologists (Memoir 36, Interregional unconformities and hydrocarbon accumulation): 7-35. Retrieved March 6, 2021. [The url is to a Rice University-hosted pdf of a book chapter adapted from the original Weimer 1984 paper.]
  3. ^ Monroe, James S.; Wicander, Reed (2009). The Changing Earth: Exploring Geology and Evolution (5th ed.). Belmont, CA: Brooks/Cole, Cengage Learning. p. 605. ISBN 978-0495554806.
  4. ^ "Oceans of Kansas Paleontology". Mike Everhart. Retrieved 2007-02-06.
  5. ^ Stokes, Keith. "Monument Rocks, the Chalk Pyramids - Kansas". www.kansastravel.org. Retrieved 7 April 2018.
  6. ^ Slingerland, Rudy; Kump, Lee R.; Arthur, Michael A.; Fawcett, Peter J.; Sageman, Bradley B.; Barron, Eric J. (1 August 1996). "Estuarine circulation in the Turonian Western Interior seaway of North America". Geological Society of America Bulletin. 108 (8): 941–952. doi:10.1130/0016-7606(1996)108<0941:ECITTW>2.3.CO;2. Retrieved 5 April 2023.
  7. ^ Lowery, Christopher M.; Leckie, R. Mark; Bryant, Raquel; Elderbak, Khalifa; Parker, Amanda; Polyak, Desiree E.; Schmidt, Maxine; Snoeyenbos-West, Oona; Sterzinare, Ericfa (1 February 2018). "The Late Cretaceous Western Interior Seaway as a model for oxygenation change in epicontinental restricted basins" (PDF). Earth-Science Reviews. 177: 545–564. Bibcode:2018ESRv..177..545L. doi:10.1016/j.earscirev.2017.12.001.
  8. ^ Stanley, Steven M. (1998). Earth system history. New York: W.H. Freeman. p. 516. ISBN 0716728826.
  9. ^ Monroe, James S. (1997). The changing earth: exploring geology and evolution (2nd ed.). Belmont, Calif.: Wadsworth Pub. p. 643. ISBN 0314095772.
  10. ^ Frazier, William J.; Schwimmer, David R. (1987). "The Tejas Sequence: Tertiary—Recent". Regional Stratigraphy of North America. pp. 523–652. doi:10.1007/978-1-4613-1795-1_9. ISBN 978-1-4612-9005-6.
  11. ^ Walker, Matt (24 February 2010). "Giant predatory shark fossil unearthed in Kansas". BBC Earth News. Retrieved 16 April 2013.
  12. ^ Mike Everhart (February 2, 2010). "Pachyrhizodus. A Large Predatory Fish from the Late Cretaceous Western Interior Sea". Oceans of Kansas Paleontology. Retrieved May 5, 2011.
  13. ^ Cumbaa, Stephen L.; Tokaryk, Tim T. (1999). "Recent Discoveries of Cretaceous Marine Vertebrates on the Eastern Margins of the Western Interior Seaway" (PDF). Saskatchewan Geological Survey Summary of Investigations. 1: 57–63. Retrieved 27 August 2021.
  14. ^ Boyles, M.J.; Scott, A.J. (1982). "Comparison of Wave-Dominated Deltaic Deposits and Associated Sand-Rich Strand Plains, Mesaverde Group, Northwest Colorado". AAPG Bulletin. 66 (5): 551–552.
  15. ^ Kauffman, E.G. (1984). "Paleobiogeography and evolutionary response dynamic in the Cretaceous Western Interior Seaway of North America". Jurassic-Cretaceous biochronology and paleogeography of North America (PDF). Vol. 27. Geological Association of Canada. pp. 273–306. Retrieved 27 August 2021.
  16. ^ Benton, S.C. (1994). "The Pterosaurs of the Niobrara Chalk." The Earth Scientist, 11(1): 22-25.
  17. ^ Da Gama, Rui O.B.P.; Lutz, Brendan; Desjardins, Patricio; Thompson, Michelle; Prince, Iain; Espejo, Irene (November 2014). "Integrated paleoenvironmental analysis of the Niobrara Formation: Cretaceous Western Interior Seaway, northern Colorado". Palaeogeography, Palaeoclimatology, Palaeoecology. 413: 66–80. Bibcode:2014PPP...413...66D. doi:10.1016/j.palaeo.2014.05.005.
  18. ^ Moss, Rycroft G. (May 2004) [1 December 1932]. "Bulletin 19: The Geology of Ness and Hodgeman Counties, Kansas". Bulletin of the University of Kansas—Lawrence. 33 (18): Stratigraphy: Rocks Exposed. Retrieved 2020-11-17.
  19. ^ Prothero, Donald R. (2013). Bringing fossils to life : an introduction to paleobiology (Third ed.). New York: Columbia University Press. p. 172. ISBN 9780231158930.
  20. ^ Ludvigsen, Rolf; Beard, Graham (1997). West Coast Fossils: A Guide to the Ancient Life of Vancouver Island. Harbour Pub. pp. 102–103. ISBN 9781550171792.

Further reading edit

  • Kauffman, Erle G.; Caldwell, W.G.E. (1993). "The Western Interior Basin in Space and Time". In Caldwell, W.G.E.; Kauffman, Erle G. (eds.). Evolution of the Western Interior Basin. Volume 39 of Geological Association of Canada Special Paper. St. John's, NL: Geological Association of Canada. Retrieved 2022-02-13.

External links edit

  •   Media related to Cretaceous Seaway at Wikimedia Commons
  • Marine Reptiles of South Dakota
  • Paleo Map Project
  • Cretaceous paleogeography, southwestern US

December 08, 2023
western, interior, seaway, also, called, cretaceous, seaway, niobraran, north, american, inland, western, interior, large, inland, that, split, continent, north, america, into, landmasses, ancient, which, existed, from, early, late, cretaceous, million, years,. The Western Interior Seaway also called the Cretaceous Seaway the Niobraran Sea the North American Inland Sea and the Western Interior Sea was a large inland sea that split the continent of North America into two landmasses The ancient sea which existed from the early Late Cretaceous 100 million years ago to the earliest Paleocene 66 Ma connected the Gulf of Mexico through the United States and Canada to the Arctic Ocean The two land masses it created were Laramidia to the west and Appalachia to the east At its largest extent it was 2 500 feet 760 m deep 600 miles 970 km wide and over 2 000 miles 3 200 km long Map of North America with the Western Interior Seaway during the Campanian Contents 1 Origin and geology 2 Fauna 3 See also 4 References 5 Further reading 6 External linksOrigin and geology edit nbsp A broken concretion with fossils inside late Cretaceous Pierre Shale near Ekalaka Montana nbsp Monument Rocks Kansas located 25 miles south of Oakley By Late Cretaceous times Eurasia and the Americas had separated along the south Atlantic and subduction on the west coast of the Americas had commenced resulting in the Laramide orogeny the early phase of growth of the modern Rocky Mountains The Western Interior Seaway may be seen as a downwarping of the continental crust ahead of the growing Laramide Rockies mountain chain 1 The earliest phase of the Seaway began in the mid Cretaceous period when an arm of the Arctic Ocean transgressed south over western North America this formed the Mowry Sea so named for the Mowry Shale an organic rich rock formation 1 In the south the Gulf of Mexico was originally an extension of the Tethys Sea In time the southern embayment merged with the Mowry Sea in the late Cretaceous forming the complete Seaway creating isolated environments for land animals and plants 1 Relative sea levels fell multiple times as a margin of land temporarily rose above the water along the ancestral Transcontinental Arch 2 each time rejoining the separated divergent land populations allowing a temporary mixing of newer species before again separating the populations At its largest the Western Interior Seaway stretched from the Rockies east to the Appalachians some 1 000 km 620 mi wide At its deepest it may have been only 800 or 900 metres 2 600 or 3 000 ft deep shallow in terms of seas Two great continental watersheds drained into it from east and west diluting its waters and bringing resources in eroded silt that formed shifting delta systems along its low lying coasts There was little sedimentation on the eastern shores of the Seaway the western boundary however consisted of a thick clastic wedge eroded eastward from the Sevier orogenic belt 1 3 The western shore was thus highly variable depending on variations in sea level and sediment supply 1 Widespread carbonate deposition suggests that the Seaway was warm and tropical with abundant calcareous planktonic algae 4 Remnants of these deposits are found in northwest Kansas A prominent example is Monument Rocks an exposed chalk formation towering 70 feet 21 m over the surrounding range land It is designated a National Natural Landmark and one of the Eight Wonders of Kansas It is located 25 miles 40 km south of Oakley Kansas 5 The Western Interior Seaway is believed to have behaved similarly to a giant estuary in terms of water mass transport Riverine inputs exited the seaway as coastal jets while correspondingly drawing in Tethyan waters from the south and Boreal waters from the north 6 During the late Cretaceous the Western Interior Seaway went through multiple periods of anoxia when the bottom water was devoid of oxygen and the water column was stratified 7 At the end of the Cretaceous continued Laramide uplift hoisted the sandbanks sandstone and muddy brackish lagoons shale thick sequences of silt and sandstone still seen today as the Laramie Formation while low lying basins between them gradually subsided The Western Interior Seaway divided across the Dakotas and retreated south towards the Gulf of Mexico This shrunken and final regressive phase is sometimes called the Pierre Seaway 1 During the early Paleocene parts of the Western Interior Seaway still occupied areas of the Mississippi Embayment submerging the site of present day Memphis Later transgression however was associated with the Cenozoic Tejas sequence rather than with the previous event responsible for the Seaway 8 9 10 Fauna editThe Western Interior Seaway was a shallow sea filled with abundant marine life Interior Seaway denizens included predatory marine reptiles such as plesiosaurs and mosasaurs Other marine life included sharks such as Squalicorax Cretoxyrhina and the giant shellfish eating Ptychodus mortoni believed to be 10 metres 33 ft long 11 and advanced bony fish including Pachyrhizodus 12 Enchodus and the massive 5 metre 16 ft long Xiphactinus larger than any modern bony fish 13 Other sea life included invertebrates such as mollusks ammonites squid like belemnites and plankton including coccolithophores that secreted the chalky platelets that give the Cretaceous its name foraminiferans and radiolarians 14 15 The Western Interior Seaway was home to early birds including the flightless Hesperornis that had stout legs for swimming through water and tiny wings used for marine steering rather than flight and the tern like Ichthyornis an early avian with a toothy beak Ichthyornis shared the sky with large pterosaurs such as Nyctosaurus and Pteranodon Pteranodon fossils are very common it was probably a major participant in the surface ecosystem though it was found in only the southern reaches of the Seaway 16 Inoceramids oyster like bivalve molluscs were well adapted to life in the oxygen poor bottom mud of the seaway 17 These left abundant fossils in the Kiowa Greenhorn Niobrara Mancos and Pierre formations There is great variety in the shells and the many distinct species have been dated and can be used to identify specific beds in those rock formations of the seaway Many species can easily fit in the palm of the hand while some like Inoceramus Haploscapha grandis 18 could be well over a meter in diameter Entire schools of fish sometimes sought shelter within the shell of the giant Platyceramus 19 The shells of the genus are known for being composed of prismatic calcitic crystals that grew perpendicular to the surface and fossils often retain a pearly luster 20 nbsp Artist s impression of a Cretoxyrhina and two Squalicorax circling a dead Claosaurus in the Western Interior Seaway nbsp Elasmosaurus platyurus in the Rocky Mountain Dinosaur Resource Center in Woodland Park Colorado nbsp Inoceramus an ancient bivalve from the Cretaceous of South Dakota See also edit nbsp Oceans portalGeology of the Bryce Canyon area Geology of the area in Utah Hudson Seaway Major seaway of North America during the Cretaceous Period Lake Agassiz Large lake in central North America at the end of the last glacial period Sundance Sea Inland sea that existed in North America during the mid to late Jurassic Period of the Mesozoic Era Zuni sequence A Jurassic Cretaceous cratonic sequenceReferences edit a b c d e f Stanley Steven M 1999 Earth System History New York W H Freeman and Company pp 487 489 ISBN 0 7167 2882 6 R J Weimer 1984 J S Schlee ed Relation of unconformities tectonics and sea level changes Cretaceous of Western Interior U S A in PDF AAPG Memoir American Association of Petroleum Geologists Memoir 36 Interregional unconformities and hydrocarbon accumulation 7 35 Retrieved March 6 2021 The url is to a Rice University hosted pdf of a book chapter adapted from the original Weimer 1984 paper Monroe James S Wicander Reed 2009 The Changing Earth Exploring Geology and Evolution 5th ed Belmont CA Brooks Cole Cengage Learning p 605 ISBN 978 0495554806 Oceans of Kansas Paleontology Mike Everhart Retrieved 2007 02 06 Stokes Keith Monument Rocks the Chalk Pyramids Kansas www kansastravel org Retrieved 7 April 2018 Slingerland Rudy Kump Lee R Arthur Michael A Fawcett Peter J Sageman Bradley B Barron Eric J 1 August 1996 Estuarine circulation in the Turonian Western Interior seaway of North America Geological Society of America Bulletin 108 8 941 952 doi 10 1130 0016 7606 1996 108 lt 0941 ECITTW gt 2 3 CO 2 Retrieved 5 April 2023 Lowery Christopher M Leckie R Mark Bryant Raquel Elderbak Khalifa Parker Amanda Polyak Desiree E Schmidt Maxine Snoeyenbos West Oona Sterzinare Ericfa 1 February 2018 The Late Cretaceous Western Interior Seaway as a model for oxygenation change in epicontinental restricted basins PDF Earth Science Reviews 177 545 564 Bibcode 2018ESRv 177 545L doi 10 1016 j earscirev 2017 12 001 Stanley Steven M 1998 Earth system history New York W H Freeman p 516 ISBN 0716728826 Monroe James S 1997 The changing earth exploring geology and evolution 2nd ed Belmont Calif Wadsworth Pub p 643 ISBN 0314095772 Frazier William J Schwimmer David R 1987 The Tejas Sequence Tertiary Recent Regional Stratigraphy of North America pp 523 652 doi 10 1007 978 1 4613 1795 1 9 ISBN 978 1 4612 9005 6 Walker Matt 24 February 2010 Giant predatory shark fossil unearthed in Kansas BBC Earth News Retrieved 16 April 2013 Mike Everhart February 2 2010 Pachyrhizodus A Large Predatory Fish from the Late Cretaceous Western Interior Sea Oceans of Kansas Paleontology Retrieved May 5 2011 Cumbaa Stephen L Tokaryk Tim T 1999 Recent Discoveries of Cretaceous Marine Vertebrates on the Eastern Margins of the Western Interior Seaway PDF Saskatchewan Geological Survey Summary of Investigations 1 57 63 Retrieved 27 August 2021 Boyles M J Scott A J 1982 Comparison of Wave Dominated Deltaic Deposits and Associated Sand Rich Strand Plains Mesaverde Group Northwest Colorado AAPG Bulletin 66 5 551 552 Kauffman E G 1984 Paleobiogeography and evolutionary response dynamic in the Cretaceous Western Interior Seaway of North America Jurassic Cretaceous biochronology and paleogeography of North America PDF Vol 27 Geological Association of Canada pp 273 306 Retrieved 27 August 2021 Benton S C 1994 The Pterosaurs of the Niobrara Chalk The Earth Scientist 11 1 22 25 Da Gama Rui O B P Lutz Brendan Desjardins Patricio Thompson Michelle Prince Iain Espejo Irene November 2014 Integrated paleoenvironmental analysis of the Niobrara Formation Cretaceous Western Interior Seaway northern Colorado Palaeogeography Palaeoclimatology Palaeoecology 413 66 80 Bibcode 2014PPP 413 66D doi 10 1016 j palaeo 2014 05 005 Moss Rycroft G May 2004 1 December 1932 Bulletin 19 The Geology of Ness and Hodgeman Counties Kansas Bulletin of the University of Kansas Lawrence 33 18 Stratigraphy Rocks Exposed Retrieved 2020 11 17 Prothero Donald R 2013 Bringing fossils to life an introduction to paleobiology Third ed New York Columbia University Press p 172 ISBN 9780231158930 Ludvigsen Rolf Beard Graham 1997 West Coast Fossils A Guide to the Ancient Life of Vancouver Island Harbour Pub pp 102 103 ISBN 9781550171792 Further reading editKauffman Erle G Caldwell W G E 1993 The Western Interior Basin in Space and Time In Caldwell W G E Kauffman Erle G eds Evolution of the Western Interior Basin Volume 39 of Geological Association of Canada Special Paper St John s NL Geological Association of Canada Retrieved 2022 02 13 External links edit nbsp Media related to Cretaceous Seaway at Wikimedia Commons Marine Reptiles of South Dakota Paleo Map Project Cretaceous paleogeography southwestern US Retrieved from https en wikipedia org w index php title Western Interior Seaway amp oldid 1184472335, wikipedia, wiki, book, books, library,

article

, read, download, free, free download, mp3, video, mp4, 3gp, jpg, jpeg, gif, png, picture, music, song, movie, book, game, games.