RECENT ADVANCES IN VERTEBRATE PALEONTOLOGY OF THE UPPER CRETACEOUS TROPIC SHALE (CENOMANIAN-TURONIAN) OF SOUTHERN UTAH

For the past seven years, the Museum of Northern Arizona has conducted extensive geological and paleontological research in the Upper Cretaceous Tropic Shale (Cenomanian-Turonian) of Kane and Garfield Counties (southern Utah), in the vicinity of the Kaiparowits Basin. Much of the fieldwork in Grand Staircase-Escalante National Monument (Bureau of Land Management) and Glen Canyon National Recreation Area (National Park Service) has been directed toward improvement in the understanding of biodiversity during the marine portion of the Greenhorn Cyclothem. This research has produced important new records for short-neck plesiosaurs, fish, sharks, and one dinosaur, all placed in stratigraphic context based on the abundant record of marine invertebrates, particularly ammonoids and inoceramid bivalves. Field and laboratory work has involved college undergraduates, graduate students, volunteers, and professional colleagues. Specimens collected in collaboration with federal agencies have been accessioned by MNA for research, education, and exhibits. In 2003, a composite skeleton of a six-meter-long plesiosaur, the front half of the skeleton from Glen Canyon National Recreation Area and the rear half from Grand Staircase-Escalante National Monument, was exhibited at MNA. That skeleton was moved to the John Wesley Powell Museum in Page, Arizona as a one-year visiting exhibit in 2004-2005. Several of the projects have stimulated considerable media coverage, most recently during the 2005 excavation of a nearly complete plesiosaur skeleton. Both federal agencies have incorporated the results of this sponsored into resource management plans for fossils that will help ensure responsible decision-making by land managers.