Hell Creek Formation: A 2001 synthesis
نویسندگان
چکیده
Kirk R. Johnson* Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, Colorado 80205, USA Douglas J. Nichols U.S. Geological Survey, MS 939, Box 25046, Denver Federal Center, Denver, Colorado 80225, USA Joseph H. Hartman Department of Geology and Geological Engineering and Energy & Environmental Research Center, University of North Dakota, Grand Forks, North Dakota 58202, USA
منابع مشابه
Carbon isotope stratigraphy and correlation of plant megafossil localities in the Hell Creek Formation of eastern Montana, USA
Questions of biotic and environmental change during deposition of the Upper Maastrichtian Hell Creek Formation require a robust and replicable system for intraformational correlation of fossil localities. In this paper, we present a carbon isotope chemostratigraphic curve based on terrestrial organic carbon. Data were taken from a complete measured section spanning the full 93 m of the Hell Cre...
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Most dromaeosaurids were smallto medium-sized cursorial, scansorial, and arboreal, sometimes volant predators, but a comparatively small percentage grew to gigantic proportions. Only two such giant “raptors” have been described from North America. Here, we describe a new giant dromaeosaurid, Dakotaraptor steini gen. et sp. nov., from the Hell Creek Formation of South Dakota. The discovery repre...
متن کاملDinosaur Census Reveals Abundant Tyrannosaurus and Rare Ontogenetic Stages in the Upper Cretaceous Hell Creek Formation (Maastrichtian), Montana, USA
BACKGROUND A dinosaur census recorded during the Hell Creek Project (1999-2009) incorporates multiple lines of evidence from geography, taphohistory, stratigraphy, phylogeny and ontogeny to investigate the relative abundance of large dinosaurs preserved in the Upper Cretaceous Hell Creek Formation of northeastern Montana, USA. Overall, the dinosaur skeletal assemblages in the Hell Creek Formati...
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Modern amphibians (lissamphibians) are highly sensitive indicators of environmental disturbance. As such, fossil lissamphibians are an excellent model for testing causal hypotheses of the Cretaceous-Paleogene mass extinction and secondary effects of Deccan volcanism and a bolide impact (e.g., acid rain). We quantitatively analyzed high-resolution temporal changes in diversity and community stru...
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An end-Cretaceous nonavian dinosaur extinction and an early Paleocene mammalian radiation is documented primarily in stratigraphic sequences in eastern Montana. To determine how representative these sequences are, we extended investigation of this Cretaceous-Tertiary (K-T) transition to new areas. Studies in southwestern North Dakota and southeastern Montana provide new records of mammals throu...
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