Skip to main content Accesibility Help
×
×
Home
  • Get access
    Check if you have access via personal or institutional login
  • Cited by 7
  • Cited by
    This chapter has been cited by the following publications. This list is generated based on data provided by CrossRef.

    Retallack, Gregory J. 2009. Greenhouse crises of the past 300 million years. Geological Society of America Bulletin, Vol. 121, Issue. 9-10, p. 1441.

    Mihlbachler, Matthew C. 2008. Species Taxonomy, Phylogeny, and Biogeography of the Brontotheriidae (Mammalia: Perissodactyla). Bulletin of the American Museum of Natural History, Vol. 311, Issue. 1, p. 1.

    Conroy, Glenn C. 2006. Creating, displaying, and querying interactive paleoanthropological maps using GIS: An example from the Uinta Basin, Utah. Evolutionary Anthropology: Issues, News, and Reviews, Vol. 15, Issue. 6, p. 217.

    PEIGNÉ, STÉPHANE 2001. A primitive nimravine skull from the Quercy fissures, France: implications for the origin and evolution of Nimravidae (Carnivora). Zoological Journal of the Linnean Society, Vol. 132, Issue. 4, p. 401.

    Norris, Christopher A. 2000. The cranium ofLeptotragulus, a hornless protoceratid (Artiodactyla: Protoceratidae) from the Middle Eocene of North America. Journal of Vertebrate Paleontology, Vol. 20, Issue. 2, p. 341.

    Walsh, Stephen L. 1998. Fossil datum and paleobiological event terms, paleontostratigraphy, chronostratigraphy, and the definition of Land Mammal “Age” boundaries. Journal of Vertebrate Paleontology, Vol. 18, Issue. 1, p. 150.

    Domning, Daryl P. Emry, Robert J. Portell, Roger W. Donovan, Stephen K. and Schindler, Kevin S. 1997. Oldest West Indian land mammal: rhinocerotoid ungulate from the Eocene of Jamaica. Journal of Vertebrate Paleontology, Vol. 17, Issue. 4, p. 638.

    ×
  • Print publication year: 1996
  • Online publication date: July 2010

1 - Magnetic stratigraphy and biostratigraphy of the middle Eocene Uinta Formation, Uinta Basin, Utah

Summary

ABSTRACT

The Uinta Formation in northeastern Utah was the original basis of the Uintan land mammal “age.” Magnetostratigraphic studies were conducted in four sections in the northeastern, north-central, and northwestern Uinta Basin. The uppermost Evacuation Creek Member of the Green River Shale, and all of unfossiliferous Uinta Formation unit “A,” was of normal polarity. This normal interval probably correlates with Chron C21n (46.3-47.8 Ma), as originally suggested by Prothero and Swisher (1992). Most of Uinta “B” was reversed (= Chron C20r, 43.8-46.3 Ma). A short normal zone spanning upper Uinta “B” and lower Uinta “C” probably correlates with Chron C20n (42.5-43.8 Ma). The upper part of the Uinta “C” and the lowermost portion of the Duchesne River Formation were also reversed (= C19r, 41.4-42.5 Ma), with normal (= C19n, 41.1-41.4 Ma) and reversed (= C18r, 40.0-41.1 Ma) magnetozones in the higher part of the Brennan Basin Member.

Although the original biostratigraphic data for most Uinta Basin collections are very poor, distinctions between the faunas of Uinta “B1,” “B2,” and “C” are possible. Uinta “B1” (the “Metarhinus zone” of Osborn, 1929) spans the interval 45–46 Ma, and is characterized by overlapping ranges of the brontotheres Sthenodectes and Metarhinus, the rhinocerotoids Hyrachyus eximius, Forstercooperia grandis and Triplopus obliquidens, and the agriochoerid oreodont Protoreodon parvus. Uinta “B2” (the “Eobasileus-Dolichorhinus zone” of Osborn, 1929), including White River Pocket, spans the interval 43-45 Ma, and is characterized by the overlapping ranges of the brontotheres Sphenocoelus, Metarhinus, Eotitanotherium, the chalicothere Eomoropus, the horse Epihippus gracilis, the creodont Oxyaenodon, and the artiodactyls Diplobunops, Oromeryx, and Leptotragulus.

Recommend this book

Email your librarian or administrator to recommend adding this book to your organisation's collection.

The Terrestrial Eocene-Oligocene Transition in North America
  • Online ISBN: 9780511665431
  • Book DOI: https://doi.org/10.1017/CBO9780511665431
Please enter your name
Please enter a valid email address
Who would you like to send this to *
×