The occurrences of vertebrate fossils in the Deadhorse Coulee Member of the Milk River Formation and their implications for provincialism and evolution in the Santonian (Late Cretaceous) of North America

• Author / Creator

  Larson, Derek W.

• The Deadhorse Coulee Member of the Milk River Formation of southern Alberta preserves one of the oldest well-documented non-marine vertebrate assemblages in Canada. In this study, the taxonomic diversity of this member is updated, and vertebrate localities are placed in geographic and stratigraphic context. The stratigraphic provenance of specimens indicates all vertebrate material from this member is latest Santonian (83.5 Ma). A new species of turtle is described. Analyses of the rank and relative abundances of taxa support interpretations of this member as a prograding clastic wedge with localities approximately 40 km from the palaeoshoreline at time of deposition. Results support high local abundances of vertebrates in western North America, with faunal provincialism regulated by distance to the palaeoshoreline and mean annual temperatures. Morphologic changes in small theropod taxa through the latest Cretaceous of western North America act as a case study for evaluating species turnover of vertebrate microfossil material.

• Subjects / Keywords

  • Palaeobiogeography
  • Fossil vertebrates
  • Milk River Formation
  • Palaeontology
  • Assemblage

• Graduation date

  Fall 2010

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R33S7C

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.