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Florissant Formation
The Florissant Formation is a sedimentary geologic formation outcropping around Florissant, Teller County, Colorado. The formation is noted for the abundant and exceptionally preserved insect and plant fossils that are found in the mudstones and shales. Based on argon radiometric dating, the formation is Eocene (approximately 34 million years old ) in age and has been interpreted as a lake environment. The fossils have been preserved because of the interaction of the volcanic ash from the nearby Thirtynine Mile volcanic field with diatoms in the lake, causing a diatom bloom. As the diatoms fell to the bottom of the lake, any plants or animals that had recently died were preserved by the diatom falls. Fine layers of clays and muds interspersed with layers of ash form "paper shales" holding beautifully-preserved fossils. The Florissant Fossil Beds National Monument is a national monument established to preserve and study the geology and history of the area. History The name ''Fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tithonian
In the geological timescale, the Tithonian is the latest age of the Late Jurassic Epoch and the uppermost stage of the Upper Jurassic Series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the Kimmeridgian and followed by the Berriasian (part of the Cretaceous).See for a detailed version of the geologic timescale Gradstein ''et al.'' (2004) Stratigraphic definitions The Tithonian was introduced in scientific literature by German stratigrapher Albert Oppel in 1865. The name Tithonian is unusual in geological stage names because it is derived from Greek mythology. Tithonus was the son of Laomedon of Troy and fell in love with Eos, the Greek goddess of dawn. His name was chosen by Albert Oppel for this stratigraphical stage because the Tithonian finds itself hand in hand with the dawn of the Cretaceous. The base of the Tithonian stage is at the base of the ammonite biozone of '' Hybonoticeras hybonotum''. A global reference profi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kimmeridgian
In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 157.3 ± 1.0 Ma and 152.1 ± 0.9 Ma (million years ago). The Kimmeridgian follows the Oxfordian and precedes the Tithonian. Stratigraphic definition The Kimmeridgian Stage takes its name from the village of Kimmeridge on the Dorset coast, England. The name was introduced into the literature by French geologist Alcide d'Orbigny in 1842. The Kimmeridge Clay Formation takes its name from the same type location (although this formation extends from the Kimmeridgian stage of the Upper Jurassic into the Lower Cretaceous). It is the source for about 95% of the petroleum in the North Sea. Historically, the term Kimmeridgian has been used in two different ways. The base of the interval is the same but the top was defined by British stratigraphers as the base of the Portlandian (''sensu anglico'') whereas in France the top was defined as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Othniel Charles Marsh
Othniel Charles Marsh (October 29, 1831 – March 18, 1899) was an American professor of Paleontology in Yale College and President of the National Academy of Sciences. He was one of the preeminent scientists in the field of paleontology. Among his legacies are the discovery or description of dozens of new species and theories on the origins of birds. Born into a modest family, Marsh was able to afford higher education thanks to the generosity of his wealthy uncle George Peabody. After graduating from Yale College in 1860 he travelled the world, studying anatomy, mineralogy and geology. He obtained a teaching position at Yale upon his return. From the 1870s to 1890s, he competed with rival paleontologist Edward Drinker Cope in a period of frenzied Western American expeditions known as the Bone Wars. Marsh's greatest legacy is the collection of Mesozoic reptiles, Cretaceous birds, and Mesozoic and Tertiary mammals that now constitute the backbone of the collections of Yale's Peabo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barosaurus
''Barosaurus'' ( ) was a giant, long-tailed, long-necked, plant-eating sauropod dinosaur closely related to the more familiar ''Diplodocus''. Remains have been found in the Morrison Formation from the Upper Jurassic Period of Utah and South Dakota. It is present in stratigraphic zones 2–5.Foster, J. (2007). "Appendix." ''Jurassic West: The Dinosaurs of the Morrison Formation and Their World''. Indiana University Press. pp. 327-329. The composite term ''Barosaurus'' comes from the Greek words ''barys'' (βαρυς) meaning "heavy" and ''sauros'' (σαυρος) meaning "lizard"; thus "heavy lizard". Description ''Barosaurus'' was an enormous animal, with some adults measuring about in length and weighing about 12–20 metric tons (13–22 short tons).Paul, G.S., 2016, ''The Princeton Field Guide to Dinosaurs 2nd edition'', Princeton University Press p. 213 There are some indications of even larger individuals, such as the enormous cervical vertebra from the BYU 902 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalattosuchian
Thalattosuchia is a clade of marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are colloquially referred to as marine crocodiles or sea crocodiles, though they are not members of Crocodilia and records from Thailand and China suggest that some members lived in freshwater. The clade contains two major subgroupings, the Teleosauroidea and Metriorhynchoidea. Teleosauroids are not greatly specialised for oceanic life, with back osteoderms similar to other crocodyliformes. Within Metriorhynchoidea, the Metriorhynchidae displayed extreme adaptions for life in the open ocean, including the transformation of limbs into flippers, the development of a tail fluke, and smooth, scaleless skin. Discovery and naming The term Thalattosuchia was coined by Fraas in 1901.Fraas E. 1901. Die Meerkrokodile (Thalattosuchia n. g.) eine neue Sauriergruppe der Juraformation. ''Jahreshefte des Vereins für vaterländische Naturkunde, Württemb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metriorhynchid
Metriorhynchidae is an extinct family of specialized, aquatic metriorhynchoid crocodyliforms from the Middle Jurassic to the Early Cretaceous period (Bajocian to early Aptian) of Europe, North America and South America. The name Metriorhynchidae was coined by the Austrian zoologist Leopold Fitzinger in 1843.Fitzinger LJFJ. 1843. ''Systema Reptilium''. Wien: Braumüller et Seidel, 106 pp. The group contains two subfamilies, the Metriorhynchinae and the Geosaurinae. They represent the most marine adapted of all archosaurs. Description Metriorhynchids are fully aquatic crocodyliforms. Their forelimbs were small and paddle-like, and unlike living crocodylians, they lost their osteoderms ("armour scutes"). Their body shape maximised hydrodynamy (swimming efficiency), as they did have a shark-like tail fluke. Like ichthyosaurs and plesiosaurs, metriorhynchids developed smooth, scaleless skin. Metriorhynchids were the only group of archosaurs to become fully adapted to the marine real ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford Clay Formation
The Oxford Clay (or Oxford Clay Formation) is a Jurassic marine sedimentary rock formation underlying much of southeast England, from as far west as Dorset and as far north as Yorkshire. The Oxford Clay Formation dates to the Jurassic, specifically, the Callovian and Oxfordian ages, and comprises two main facies. The lower facies comprises the Peterborough Member, a fossiliferous organic-rich mudstone. This facies and its rocks are commonly known as lower Oxford Clay. The upper facies comprises the middle Oxford Clay, the Stewartby Member, and the upper Oxford Clay, the Weymouth Member. The upper facies is a fossil poor assemblage of calcareous mudstones. Oxford Clay appears at the surface around Oxford, Peterborough and Weymouth and is exposed in many quarries around these areas. The top of the Lower Oxford Clay shows a lithological change, where fissile shale changes to grey mudstone. The Middle and Upper Oxford Clays differ slightly, as they are separated by an argillaceou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Callovian
In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 166.1 ± 4.0 Ma (million years ago) and 163.5 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian. Stratigraphic definitions The Callovian Stage was first described by French palaeontologist Alcide d'Orbigny in 1852. Its name derives from the latinized name for Kellaways Bridge, a small hamlet 3 km north-east of Chippenham, Wiltshire, England. The base of the Callovian is defined as the place in the stratigraphic column where the ammonite genus ''Kepplerites'' first appears, which is the base of the biozone of '' Macrocephalites herveyi''. A global reference profile (a GSSP) for the base had in 2009 not yet been assigned. The top of the Callovian (the base of the Oxfordian) is at the first appearance of ammonite species '' Brightia thuouxensis''. Subdivision The Callovian is often subdivided into three substages ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Lydekker
Richard Lydekker (; 25 July 1849 – 16 April 1915) was an English naturalist, geologist and writer of numerous books on natural history. Biography Richard Lydekker was born at Tavistock Square in London. His father was Gerard Wolfe Lydekker, a barrister-at-law with Dutch ancestry. The family moved to Harpenden Lodge soon after Richard's birth. He was educated at Trinity College, Cambridge, where he took a first-class in the Natural Science tripos (1872). In 1874 he joined the Geological Survey of India and made studies of the vertebrate palaeontology of northern India (especially Kashmir). He remained in this post until the death of his father in 1881. His main work in India was on the Siwalik palaeofauna; it was published in ''Palaeontologia Indica''. He was responsible for the cataloguing of the fossil mammals, reptiles, and birds in the Natural History Museum (10 vols., 1891). He named a variety of taxa including the golden-bellied mangabey; as a taxon authority he is nam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suchodus
''Suchodus'' is an extinct genus of marine crocodyliform from the Middle to Late Jurassic period of England and France. It measured between in total body length. Taxonomy and phylogeny In the 2000s, phylogenetic analysis has shown that ''Suchodus'' is a distinct metriorhynchid genus.Young, Mark T., and Marco Brandalise de Andrade, 2009. "What is ''Geosaurus''? Redescription of ''Geosaurus giganteus'' (Thalattosuchia: Metriorhynchidae) from the Upper Jurassic of Bayern, Germany." ''Zoological Journal of the Linnean Society'', 157: 551-585.Young, Mark T., Brusatte, Stephen L., Ruta, M., Andrade, Marco B. 2009. "The evolution of Metriorhynchoidea (Mesoeucrocodylia, Thalattosuchia): an integrated approach using geometrics morphometrics, analysis of disparity and biomechanics". ''Zoological Journal of the Linnean Society'' 158: 801-859. Valid species are: *''S. brachyrhynchus'': Western Europe (England and France) of the Middle-Late Jurassic (Callovian and Oxfordian); ''Metriorh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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