7 Paleoenvironments and Paleoecology of the Upper Jurassic Morrison Formation of the Western U.S.

Monday, 23 May 2005
1:00 PM - 5:00 PM

RECENT DISCOVERIES FROM THE MORRISON FORMATION OF NORTH EAST WYOMING

Paper number: 7-1
Program: THEME SESSIONS
Time: 1:00 PM – 1:15 PM

Authors

Abstract

Since 1997 paleontological excavations have been conducted from the topmost Morrison Formation on a privately owned ridge in Weston County Wyoming by the University of Kansas and other parties. A rich vertebrate fauna has been found including members of the Dinosauria, Crocodylia, Chelonia, Mammalia and Osteichthyes. Additionally, small coal lenses and excellent floral specimens have been found in association with the vertebrate specimens.

The depositional environment is uncemented clay grading to tightly cemented, fine sand and calcite cemented nodules. A quiet fluvial environment with proximate cold water springs is posited.

Nine articulated sauropods and theropods have been recovered with elements of several more associated as well as many single theropod, sauropod, hypsilophodont and crocodile teeth. Seven of these specimens are well articulated and over 50% complete. At least five complete turtles have also been recovered.

A complete fauna listing with field maps and specific taphonomic implications will be presented and discussed as well as the paleoecological implications for this and adjacent uppermost Morrison Formation localities in North East Wyoming.