Results 241 to 250 of about 72,374 (285)

Giant ichthyosaurs of the Early Jurassic

Canadian Journal of Earth Sciences, 1996
Temnodontosaurus platyodon, from the English lower Liassic (Hettangian and Sinemurian), is a large ichthyosaur that reached an estimated length of almost 9 m (29 ft). Although represented by at least 13 specimens, few are complete, and the species cannot be described as well known. A similarly sized species from the upper Liassic (Toarcian) of Germany
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Geomagnetic polarity in the early Cretaceous and Jurassic

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1982
Abstract Knowledge of the polarity history of the Earth’s magnetic field during the Mesozoic stems primarily from oceanic (M-sequence) magnetic anomalies. Certain of these anomalies have been biostratigraphically dated from sediments immediately overlying basaltic basement at Deep Sea Drilling Project (D. S. D.
J. E. T. Channell, J. G. Ogg, W. Lowrie
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New Early Jurassic Tetrapod Assemblages Constrain Triassic-Jurassic Tetrapod Extinction Event

Science, 1987
The discovery of the first definitively correlated earliest Jurassic (200 million years before present) tetrapod assemblage (Fundy basin, Newark Supergroup, Nova Scotia) allows reevaluation of the duration of the Triassic-Jurassic tetrapod extinction event.
P E, Olsen, N H, Shubin, M H, Anders
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New early Jurassic paleopole from France and Jurassic apparent polar wander

Earth and Planetary Science Letters, 1993
Abstract A new early Jurassic paleopole for stable Europe obtained from a doleritic dyke system in Brittany, France is given at latitude 61°N and longitude 79°E (K = 36 andA95 = 10.2°) based on seven equivalent sites and more than a hundred samples demagnetized by alternating field and thermal treatments (D = 41°,I = 62°,k = 66,α95 = 7.5 ...
B. Sichler, M. Perrin
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A Late Jurassic Digging Mammal and Early Mammalian Diversification

Science, 2005
A fossil mammal from the Late Jurassic Morrison Formation, Colorado, has highly specialized teeth similar to those of xenarthran and tubulidentate placental mammals and different from the generalized insectivorous or omnivorous dentitions of other Jurassic mammals.
Zhe-Xi, Luo, John R, Wible
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Embryos of an Early Jurassic Prosauropod Dinosaur and Their Evolutionary Significance

Science, 2005
Articulated embryos from the Lower Jurassic Elliot Formation of South Africa are referable to the prosauropod Massospondylus carinatus and, together with other material, provide substantial insights into the ontogenetic development in this early dinosaur.
Reisz, R. R., Scott, D., Sues, Hans-Dieter, Evans, D. C., Raath, M. A.   +4 more
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The Late Jurassic–Early Cretaceous Rifting

2019
During the Late Jurassic and Early Cretaceous, Iberia experienced extensional and transtensional stresses leading to a complex rifting time interval. Africa–America–Europe relative motions determined the definition of the Iberian plate boundaries and the generation of rifted sedimentary basins and sub-basins along its continental margins and in the ...
Javier Martín-Chivelet, José López-Gómez, Roque Aguado, Consuelo Arias, José Arribas, María Eugenia Arribas, Marcos Aurell, Beatriz Bádenas, María Isabel Benito, Telm Bover-Arnal, Antonio Casas-Sainz, José Manuel Castro, Francisco Coruña, Ginés A. de Gea, Joan J. Fornós, Marian Fregenal-Martínez, Jesús García-Senz, David Garófano, Bernadí Gelabert, Jordi Giménez, Laura González-Acebrón, Joan Guimerà, Carlos L. Liesa, Ramón Mas, Nieves Meléndez, José Miguel Molina, Josep Anton Muñoz, Rocío Navarrete, Marina Nebot, Luis Miguel Nieto, Silvia Omodeo-Salé, Antonio Pedrera, Carlos Peropadre, Isabel Emma Quijada, María Luisa Quijano, Matías Reolid, Alejandro Robador, Juan Pedro Rodríguez-López, Antonio Rodríguez-Perea, Idoia Rosales, Pedro A. Ruiz-Ortiz, Francesc Sàbat, Ramón Salas, Ana R. Soria, Pablo Suarez-Gonzalez, Lorenzo Vilas   +45 more
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Astronomical pacing of methane release in the Early Jurassic period

Nature, 2005
A pronounced negative carbon-isotope (delta13C) excursion of approximately 5-7 per thousand (refs 1-7) indicates the occurrence of a significant perturbation to the global carbon cycle during the Early Jurassic period (early Toarcian age, approximately 183 million years ago). The rapid release of 12C-enriched biogenic methane as a result of continental-
David B, Kemp, Angela L, Coe, Anthony S, Cohen, Lorenz, Schwark   +3 more
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The two Early Toarcian (Early Jurassic) extinction events in ammonoids

Lethaia, 2004
The Early Toarcian (Early Jurassic) biological crisis was one of the ‘minor’ mass extinctions. It is linked with an oceanic anoxic event. Fossil data from sections located in northwestern European (epicontinental platforms and basins) and Tethyan (distal, epioceanic) areas indicate that Late Pliensbachian–Early Toarcian ammonoids experienced two ...
Fabrizio Cecca, Francesco Macchioni
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SCLEROCHRONOLOGY OF THE EARLY JURASSIC LITHIOTID BIVALVES: SEARCHING FOR SYMBIOSIS

Geological Society of America Abstracts with Programs, 2016
The Lithiotid bivalves (Lithiotis, Cochlearites and Lithioperna) were an aberrant bivalve group which arose during the Pliensbachian stage of the Early Jurassic, following a 10 million year post-Triassic extinction “reef gap”. During this period of the near-complete eradication of reef-building corals, the Lithiotids became the dominant calcifiers in ...
Killam, Daniel, Clapham, Matthew, POSENATO, Renato, Franceschi, Marco   +3 more
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