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the Cretaceous - 144 to 65 million years ago

World Paleogeography: The second major episode of continental rifting in the breakup of Pangea began in the Early Cretaceous. South America and Africa separated slowly from south to north creating the South Atlantic Ocean, while India and Madagascar rifted away from the western margins of Australia and Antarctica to form the Indian Ocean. At the same time, rifting between North America and Europe began, and Iberia rotated counter-clockwise away from France. Throughout the Cretaceous, sea level was an average of 100 meters higher than today due to continental rifting and sea-floor spreading. Shallow seaways spread over many of the continents, including North America, South America, Africa, and Eurasia. Climate was globally warm during the Cretaceous, partly due to the mediating climatic effects of the shallow seas, and partly because the continental positions allowed warm waters to circulate around the globe.

North American Paleogeography: During the Cretaceous, North America was moving northwest, closer to its present position. A large inland sea spread over much of central and southern North America. Low mountains stood out along the modern Appalachian Mountains and lowlands dominated from the modern Great Lake States into eastern Canada. Subduction along the western continental margin accelerated, adding intrusive and extrusive igneous rocks to the ancestral Sierra Nevada. The ancestral Rocky Mountains were uplifted, and exotic terranes were being added to its western margin.

Paleontology: The Cretaceous Period may be best known for its ending. Marking the boundary between the Mesozoic and Cenozoic Eras, the end of the Cretaceous is defined by one of the most famous mass extinctions in the history of life on Earth. It has been estimated that perhaps 60-70% of all marine species and nearly 15% of all terrestrial genera, including many mammals, went extinct at the end of the Cretaceous. Perhaps the most famous victims were the dinosaurs — only their descendents, the birds, survived. In fact, all land animals larger than about 20 kg (50 lbs., about the size of a large dog) died out. Gone too were many species of echinoderms, brachiopods, and molluscs, including ammonites and the reef-building rudist bivalves.

North America Today

Much of northeastern North America has been above sea level since the Cretaceous. These highlands have been shedding sediment into lower areas instead of accumulating it. Therefore, there are few rocks of this age in northeastern states. Exposures of Cretaceous rocks in the U.S. can be found in New Jersey, around the Appalachians from North Carolina to Tennessee, and west of the Mississippi River (from Texas north to Montana and west to California). Exposures of Cretaceous rocks cover much of Alberta and Saskatchewan, as well as parts of British Columbia. Scattered Cretaceous age outcrops also occur in all four regions of Mexico.

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Careers | Organizations | Education and Exhibits | Research and Collections | Resources


Degree and Certificate Programs (showing 1 of 1 listings)

Montana State University- Earth Sciences: Train to be a paleontologist in the MSU Undergraduate and Graduate Paleontology Programs. The Earth Sciences Department at MSU caters to both paleobiology and taphonomy interests.

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Career Paths (showing 1 of 1 listings)

Paleoprofile of Kristi Curry Rogers: Biographical sketch of paleontologist Kristi Curry Rogers. Learn about her work in dinosaur paleontology in Montana and Madagascar.

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Parks (showing 1 of 1 listings)

Dinosaur Valley State Park: Dinosaur Valley State Park, opened to the public in 1972, is located just northwest of Glen Rose in Somervell County, astride the Paluxy River. This park contains some of the best preserved dinosaur tracks in the world.

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Societies and Clubs (showing 1 of 1 listings)

North Dakota Geological Survey Fossil Resource Program: Links to all varieties of information on North Dakota paleontology, including research papers, museums, and background information on the state's fossils.

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Museums (showing 3 of 16 listings)

University of Alaska Museum of the North--Arctic Dinosaurs and More: This is the principal natural history museum of Alaska and the Arctic. It features collections & exhibits of Arctic dinosaurs, Quaternary mammals, including unequaled mummified remains,Teriary and Mesozoic collections of mollusks. 

The Regional Museum Mixteco: This museum in Tepexi de Rodriguez, Puebla, Mexico houses fossils from the Tlayua quarry, as well as local archeological items.

Mayborn Museum Complex, Waco, TX: The Mayborn Museum is the home of one of the oldest natural history collections in Texas. Once part of the Strecker Museum, the collection is now displayed as part of the Mayborn’s Waco at the Crossroads of Texas exhibits. These exhibits explore the Mesozoic and Cenozoic Eras in Central Texas and feature amazing fossil finds from the area including a plesiosaur and a 75 million year old marine turtle. The Mayborn also offers the only way to experience the internationally known Waco Mammoth Site, the world’s largest concentration of Columbian mammoths dying from a single event. The Waco Mammoth Site exhibit includes original casts of the fossils, video, and exploration stations. With something for everyone, the Mayborn is a must see for anyone interested paleontology, mammoths, or just the unique history of Central Texas.

More Museums

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Colleges and Universities (showing 1 of 1 listings)

Stony Brook University Vertebrate Fossil Preparation Laboratory: Information on the people and research projects at Stony Brook University; also includes general information on fossil preparation techniques.

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Government Agencies (showing 2 of 2 listings)

Delaware Geological Survey: This Geological Survey site has pages on the fossils, and dinosaurs, of Delaware.

Dr. John D. Cooper Archaeological and Paleontological Center: The Dr. John D. Cooper Archaeological and Paleontological Center is dedicated to preserving the natural and cultural history of Orange County, California. The Cooper Center, a partnership between O.C. Parks and California State University Fullerton, is committed to the preservation, curation, and management of the fossils and artifacts collected within the County.

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Education and Exhibits

Physical Exhibits (showing 3 of 4 listings)

Hall of Florida Fossils: Evolution of Life and Land: Drawing upon the museum's internationally acclaimed fossil collections, this exhibit encapsulates the last 65 million years of Earth's history.

Lone Star Dinosaurs: Exhibit overview and excavation photo albums of seven dinosaurs discovered in Texas, six of the dinosaurs are currently featured in the Fort Worth Museum of Science and History's Lone Star Dinosaurs exhibit.

Maryland Science Center Exhibits: This site details information on exhibits at the Maryland Science Center, including Dinosaur Mysteries (featuring a cast T. rex skeleton, models of Maryland's dinosaurs, and other exhibits), Fossil Quest, and TerraLink (highlighting geology and other earth sciences). 

More Physical Exhibits

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Virtual Exhibits (showing 3 of 14 listings)

Dinobuzz: Current Topics Concerning Dinosaurs: Unfortunately, the science of dinosaur paleontology is often obscured by the fantasy that surrounds it. This site from the UC Museum of Paleontology addresses fact vs. fiction on some popular dinosaur-related topics.

Ancient Denvers: Ancient Denvers is a virtual exhibit that highlights 13 reconstructions of ancient Colorado landscapes.

Virtual Museum of Fossils: Geosciences, at Georgia's Valdosta State University, presents an interactive virtual museum of invertebrate and vertebrate fossil specimens. Explore the collection by animal, or by time period from Precambrian to Quaternary. Maps are detailed and include ecosystem distribution. Fossil photographs, many showing multiple views, list information about where the fossil was found, and how it is categorized taxonomically. Some pages feature a drawing of the animal's skeleton showing the fossil bone in red.

More Virtual Exhibits

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Research and Collections

Ongoing Research Projects (showing 3 of 12 listings)

Sam Noble Oklahoma Museum of Natural History: On the campus of the University of Oklahoma in Norman. One of the finest university-based museums in the nation, with an active Paleontology research program and extensive collections. 

Database of the Former British Petroleum Microfossil Collection at the NHM, London: In 1991 BP donated to The Natural History Museum their Micropalaeontological Collection. This collection has an extensive geographical and stratigraphic coverage and is a record of BP’s exploration activity since the 1950s.

The database hold details of material from over 3,500 individual well runs. The collection includes micropalaeontological assemblage slides and residues; palynological slides and residues and nannofossil slides from wells and outcrop from over 120 countries world-wide.

Duxbury (1983) database of Cretaceous dinoflagellate cysts: Duxbury (1983) is one of the most important publications for workers in Cretaceous dinoflagellate cysts. The collection, housed in the Micropalaeontology Division, consists of over 100 slides. The publication describes 102 taxa of which 2 genera and 20 species are described as new.

More Ongoing Research Projects

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Researchers (showing 3 of 5 listings)

Canadian Fossil Discovery Centre: The museum hosts the largest collection of marine reptile fossils in Canada and programs for all ages. The museum website includes fossil images as well as additional information about fossils, fossil collecting, and geologic processes.

University of Kansas Paleobotanical Collection: Collection of fossil plants currently housed at the University of Kansas.

David T. King's Homepage: David King, Jr., a professor of geology at Auburn University, has assembled a web page detailing his work on Alabama geology. Topics covered here include meteor impacts in Alabama, Alabama dinosaurs, and the Paleozoic and Mesozoic geology of the state. Numerous scientific papers are posted here.

More Researchers

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Databases (showing 3 of 4 listings)

New Mexico Museum of Natural History and Science Web-based Paleo-database Home Page: Search the fossil collections of the New Mexico Museum of Natural History and Science. Listings by Kingdom down to species, era, epoch, group, formation, country, New Mexico county, and map ID. Many listings contain images of the fossils (including all holotypes.) 

The Paleointegration Project: The PaleoIntegration Project (PIP) is facilitating interoperability between global-scale fossil and sedimentary rock databases (e.g. The Paleobiology Database and the Paleogeographic Atlas Project), enabling a greater understanding of the life, geography and climate of our planet throughout the Phanerozoic. Databases can be searched via text and interactive maps, and by any combination of age, location, or content. Results can be plotted on present- and paleo- maps or downloaded for detailed analyses.

Fossils in My Back Yard: Explore a geologic map of Iowa, county by county, to see lists and photos of fossils in the collections of the University of Iowa Paleontology Repository.

More Databases

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Annotated Bibliographies (showing 1 of 1 listings)

Bibliography of Paleobotany: A bibliographic database of paleobotany including more than 56,000 entries. It also includes references on Antarctic geology and paleontology and citations on Women in Science.

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Maps (showing 1 of 1 listings)

Paleogeography and Geologic Evolution of North America: The images presented here show the paleogeography of North America over the last 550 million years of geologic history.

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History of Paleontology (showing 3 of 3 listings)

Dinosaurios en México: A history of dinosaur discoveries in Mexico.

The Bone Feud: The Bone Feud is a novel about the fossil feud between paleontologists Edward Drinker Cope and O.C. Marsh in the 1870s. It's a fictionalized but well-researched and entertaining take on the story, and is quite suitable for young adults.

Hadrosaurus.com: Scientific and historical information about the first dinosaur skeleton from North America, a duck-billed dinosaur called Hadrosaurus.

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Field Guides (showing 3 of 3 listings)

Oceans of Kansas: Photographs, artwork, historical papers, and other information on the sea creatures, especially mosasaurs and plesiosaurs, that lived in the Western United States during the Cretaceous period.

Fossil Cephalopods in Utah: A reference to help provide information on the identity, biostratigraphy and location of fossil cephalopods found in the state of Utah.

Bliss Dinosaur Ranch: This site showcases a large number of Cretaceous fossils (Hell Creek Formation) on a private ranch on the Montana-Wyoming border. The bones of Triceratops and pachycephalosaurs have been found, as well as numerous mammal teeth.

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Courses and Lectures (showing 1 of 1 listings)

Paleogeography of the Southwestern U.S.: The paleogeography of the southwestern U.S. from 1.8 billion years ago to 10 million years ago. Text and images by Dr. Ron Blakey from Northern Arizona University.

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Image Collections (showing 3 of 4 listings)

Royal Ontario Museum dinosaur images: An excellent collection of dinosaur fossil images, many of the fossils represented being from Dinosaur Provincial Park in Alberta. There are also many photos of museum displays and photos taken in the field.

Texas Fossils: A collection of fossils, found in Hood Co., Jack Co., Fannin Co., and surrounding areas with over 200 specimens.

Dinosaurs of Late Cretaceous Alaska: Find out more about Alaskan dinosaurs on this Alaska Museum of Natural History page.

More Image Collections

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General Reference (showing 3 of 12 listings)

SkeletalDrawing.com: An anatomical resource for artist and amateurs who want to learn about the science behind restoring prehistoric animals, with an emphasis on dinosaurs. Includes many skeletal reconstructions.

Carrot River Valley Fossils: A page describing the fossils recovered from the Carrot River Valley, Saskatchewan.

Cretaceous paleoflora of Coahuila, Mexico: A discussion of fossil plants from the Elm Formation accompanied by photographs.

More General Reference

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