It split north america into two halves for most of the mid and latecretaceous period. The only nonmarine cretaceous unit in nebraska is the dakota formation. Seven key time slice maps, 115, 105, 92, 85, 77, and 72 ma overlap with the wis maps. Throughout most of the cretaceous period, rapid seafloor spreading contributed to a rise in global sea levels.
It probably lived in shallow depths and would have been a fast moving muscular squid as demonstrated by its robust gladius providing anchorage for powerful musculature. The overall goal was to construct a subsurface transect of midcretaceous strata that were deposited in the u. Paleobiogeography of the cretaceous western interior. Regionally, this caused massive flooding of the lowlying regions of central north america and formed the western interior seaway which expanded across north america the seaways coastlines, depth and length fluctuated throughout the cretaceous period. Ichthyodectes ctenodon meaning fish biter with comb teeth large ichthyodectid growing to more than 10 feet long that lived in the u. The rise of the rocky mountains and the appearance of. 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 existed during the mid to late cretaceous period as well as the very early paleogene, splitting the continent of north america into two landmasses, laramidia to the west and appalachia to the east.
Chapter 9 the western interior basin sciencedirect. In this documentary, we learn about the western interior cretaceous seaway, a shallow inland sea that swept through central north america during the cretaceous period, approximately 70 to 100. But during the cretaceous period, ninety million years ago, most of nebraska was at the bottom of the western interior seaway that separated north america into laramidia west and appalachia east. It was up to feet deep, 600 miles wide and over miles long. I would also like to thank my committee members dr. Cold methane seeps were common in the late cretaceous western interior seaway of north america. The skies over the western interior seaway teemed with flying reptiles uniquely. Early cretaceous to paleocene paleogeography of the western. Western interior seaway 100 million years ago western interior seaway during the midcretaceous, some 100 million years ago the western interior seaway, also called the cretaceous seaway, the niobraran sea, and the north american inland sea, was a huge inland sea that split the continent of north america into two halves during most of the early and midcretaceous period. This scene represents a moment in time 83 million years ago, in what is now the state of kansas, which was covered by a body of water known as the western interior seaway and populated by diverse, prehistoric marine life. Estuarine circulation in the turonian western interior.
They provided a habitat for a diverse array of fauna including ammonites. Was the western interior seaway stratified evidence from late campanian and early maastrichtian late cretaceous shipworms peter j. Global sea levels were much higher than today, and a large seaway disected north america into several large landmasses. T1 estuarine circulation in the turonian western interior seaway of north america. The western interior seaway, also called the cretaceous seaway, the niobraran sea, and the north american inland sea, was a huge inland sea that split the continent of north america into two halves during most of the mid and late cretaceous period. The newest named member of the tyrannosaur family tree is leading evolutionary paleontologists to redraw the map of how tyrannosaurs evolved. The area just to the east of the new mountain range flexed downward, creating a shallow north american seaway known as the western interior. The map at the left is a reconstruction of north america from 75 million years ago campanian stage. The western interior seaway was a large inland sea that existed during the mid to late cretaceous period as well as the very early paleogene, splitting the continent of north america into two. Animation by ludvig rhodin, james adson, and joseph rogers. The shoreline estimates he produced rely on the distribution of index fossils. At its maximum extent, the seaway extended a distance of more than 3,000 mi from the arctic ocean to the gulf of mexico kauffman, 1977. Late cretaceous faunal dynamics in the western interior.
This terrestrial unit was composed mostly of coastal plain and estuary deposits. Farther north in new mexico these five ammonite zones occur over a stratigraphic. Herbert for their help and suggestions with this study. Subsurface stratigraphic cross sections of cretaceous and. Display poster, with optional framing and stand, specifically designed to complement our western interior seawayrelated fossil replica exhibits. Active volcanism during the sevier orogeny was the product of partial melting.
Paleogeography of the late cretaceous of the western interior of middle north. Stratigraphy and paleoenvironments of the cretaceous western interior seaway, usa. Posts about western interior seaway written by jake buehler. Search and discovery featured articles source rock evaluation from well logs geomechanical properties of unconventional resources gas hydratebearing reservoirs conditioning prestack seismic data. New tyrannosaur evolutionary timeline answers in genesis. Western interior seaway wis, we provide a broad overview of the paleogeographical history of. Also known as the cretaceous seaway, the niobraran sea, and the north american inland sea, it stretched from the arctic to the gulf of mexico, and at its widest, in the middle cretaceous, it extended from presentday utah to. Note that the shorelines of the western interior seaway changed almost continuously as sea levels went up and down, and the western half of north america was pushed upward by the collision of continental plates. Western interior seaway simple english wikipedia, the. Western interior seaway usgs publications repository. Mountains, seaway triggered north american dinosaur surge date.
It existed at its fullest extent from the midlate cretaceous period. At its greatest extent it was 600 miles 970 km wide, 2,000 miles 3,200 km long, and had a depth maximum depth of 2,500 feet 700 m. Isolated and stuck in the desolate landscape, they are forced to face their demons, paralleling their. Lamniform sharks from the cenomanian upper cretaceous of. The western interior foreland basin wifb initiated in the middle jurassic. It was the age of dinosaurs, and much of what would become west texas was submerged in a warm inland sea. After a failed familicide, michael kidnaps his wife nina and children and takes them on a hunt for dinosaur fossils in utahs western interior seaway. It is exhibit quality, not a halftoned, massproduced poster. Western interior seaway during the midcretaceous, about 100 million years ago. This poster is printed ondemand inhouse at bhi on our highquality, sevencolor, photographic large format printer. This body of water has been named the western interior seaway.
Terrestrial pollen has been used quite extensively for relative age dating and environmental interpretations of nonmarine sediments adjacent to the cretaceous western interior seaway. Mountains, seaway triggered north american dinosaur surge. Western interior seaway during the late cretaceous period. During the cretaceous period, along the western shore of the western interior seaway there was active volcanism and foreland subsidence brought about by the sevier orogeny, formed by the convergence of the oceanic farallon and kula plates with the north american plate. The western interior basin, which was occupied for about 100 million years by the western interior seaway, is one of the largest, best preserved, and most intensively studied of. In paleogeography, a transgression event is where the worlds sea levels rise. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The western interior seaway lasted for about 60 million years, longer than the human species, but all things must come to an end and the last we saw of the seaway was 70 million years ago. Climate change likely dried up the interior seaway and held its waters frozen in the poles. A northeastern extension of the western interior seaway frequently covered much of minnesota during this time. Fish species in the western interior seaway wikipedia.
This cretaceous seaway was filled with many fierce predators, and, as. The tyrannosaur family tree, for instance, has up to now presumed that evolving dinosaurs with advanced specializations trekked across the bering strait to populate asia. Western interior seaway during early campanian times illustrating proposed biogeographic subprovinces based on vertebrate distribution patterns. The western interior seaway was a large inland sea that existed during the mid to late cretaceous period as well as the very early paleogene, splitting the. The western interior seaway is an ancient intracontinental seaway that occupied much of modern western north america and existed throughout much of the cretaceous period. He created over 80 maps to estimate the locations of strandlines of the western shore of the western interior seaway. Nebraska is located in the center of the united states, almost equidistant from the atlantic and pacific oceans. Isolated and stuck in the desolate landscape, they are forced to face their demons, paralleling their existence to the extinction of the creatures they search for.
The western interior seaway also covered most of the shallow southeastern united states, including every state adjacent to the modernday gulf of mexico. This animation shows the movement of shorelines through colorado and surrounding areas from 100 million to 66 million years ago. The western interior seaway, was a large inland sea that started to expand in the early cretaceous period, though geological evidence suggests it started to expand in the late jurassic period. Extent of western interior seaway during peak late turonian transgression watinoceras time. Late cretaceous chronology of western interior basin, united states. Students then glue the cards on the appropriate places on the timeline. The sevier mountains can be seen developing to the west, and early laramide uplifts begin to appear in colorado and wyoming. The presence of similarly advanced specializations far to the south 10 million years earlier demands the existence of a hitherto yetundiscovered. This dvd uses a different approach compared to previous releases from colorado plateau geosystems in that it packs 60 time slices into two geologic periods, jurassic and cretaceous. In summary, tusoteuthis was probably a major component of the ecosystem of the western interior seaway and a favoured prey item of assorted marine predators. Western interior seaway carnegie museum of natural history.
The western interior seaway was created during one of the greatest transgression events of all time. The upper part of the dakota sandstone exposed on the sevilleta national wildlife refuge, northern socorro county, new mexico, is a condensed, upper cretaceous, marine succession spanning the first five middle cenomanian ammonite zones of the u. Tusoteuthis and cretaceous giant squid the octopus news. Western interior seaway 161 ma jurassic late western interior seaway 170 ma jurassic middle western interior seaway 185 ma jurassic early global animation sample. Shit you didnt know about biology unrepentantly celebratory insights into life on earths underappreciated, underacknowledged, and utterly amazing stories. Peters experience and knowledge of the cretaceous western interior seaway, detailed editing skills, and patients made all difference during the completition of this work. Geomechanical properties of unconventional resources. The western interior seaway, also called the cretaceous seaway, the niobraran sea, and the north american inland sea, was a huge inland sea that split the. The late cretaceous has especially closely spaced time slices, many less than. Allow yourself to be taken back into deep geologic time when strange creatures roamed the earth and western north america looked completely unlike the modern landscape. Because the composition of the rocks retrieved from the moon by the apollo missions is very similar to rocks from the earth, it is thought that the moon formed as a result of a collision between the young earth and a marssized body, sometimes called theia, which accreted at a lagrangian point 60 ahead or behind the earth. No slide show is available for the cretaceous in minnesota. It was up to 2,500 feet 760 m deep, 600 miles 970 km wide and over 2,000 miles 3,200 km long. Cretaceous western interior seaway biology dictionary.
A muddy coastline gave way to a shallow sea floor that was home to oysters, clams, and other typical marine organisms. The sevier mountains can be seen developing to the west, and early laramide uplifts begin to appear in colorado and wyoming as the seaway recedes. From about 100 million to 68 million years ago, a shallow seaway covered much of the center of north america. This dvd uses a different approach compared to previous releases from colorado plateau geosystems in that it packs 60 time slices into. Unearthed in 2009 from the upper cretaceous portion of southern utahs grand staircase in the wahweap formation, conventionally dated at about 80 million years, the new tyrannosaur species has been dubbed lythronax argestes. The western interior seaway, also called the cretaceous seaway, the niobraran sea, and the north american inland sea, was a huge inland sea that split the continent of north america into two halves during most of the mid and latecretaceous period. This site discusses the physiography, origin, evolution and biologic significance of this intriguing geologic feature. Temperature and salinity of the late cretaceous western. Stratigraphy and paleoenvironments of the cretaceous.
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