Excavated and In Situ Dinosaur Footprints from the Murray Quarry (Early Jurassic East Berlin Formation), Holyoke, Massachusetts, USA

The Murray Quarry was operated during the 1920s and 1930s in sediments of the Early Jurassic East Berlin Formation. I examined 149 footprints of bipedal dinosaurs on three excavated slabs from the Murray Quarry and the in situ track bed. The three slabs I examined are on display at Forest Park, Springfield, MA; the Wistariahurst Museum in Holyoke, MA; and Mount Holyoke College in South Hadley, MA. The footprints belong to three ichnogenera, Eubrontes, Anchisauripus, and Grallator; however, evidence such as length parameters suggests that these ichnogenera might be synonymous. Most of the footprints are referable to Eubrontes and Anchisauripus, which are large- and medium-sized ichnotaxa, respectively. Only two footprints are referable to Grallator, a small ichnotaxon. These ichnotaxa are thought to have been made by theropods, suggesting that there is a preservation bias in favor of carnivores, or that theropods dominated the fauna. The variable morphology of the footprints suggests that they were made over a period of time during which the substrate desiccated. Major results included a high percentage of trotting dinosaurs based on trackway evidence, 43% of the total number of trackways. Additionally, two trackways show evidence for running. There are no preferred trackway orientations.

Keywords:

• ichnology
• dinosaur footprints
• East Berlin Formation
• Newark Supergroup

ACKNOWLEDGEMENTS

This paper is the culmination of a senior honors thesis at the University of Massachusetts Amherst and was partially funded by a grant from the Commonwealth College (Honors Program) at the University. I wish to thank Margery Coombs for her continued support and guidance throughout the duration of this research project. Patrick Sullivan, Carol Constant, and Mark McMenamin are warmly thanked for providing access to the Forest Park, Wistariahurst Museum, and Mt. Holyoke College slabs, respectively. William Murray permitted the re-excavation of the Murray Quarry, and for that I thank him. Dariusz Mokos helped me by aiding in construction of plaster casts of the Forest Park Slab footprints. Margery and Walter Coombs reviewed the results of my research at Forest Park before I presented it at the annual Society of Vertebrate Paleontology meeting in 2002. Margery Coombs, Walter Coombs, Eric Dewar, and Kevin Getty assisted in excavating the Murray Quarry. Without their help I would not have been able to finish the research at the Murray Quarry in a timely fashion. Elizabeth Brainerd helped me with computer-related issues during my research. Emma Rainforth provided valuable information and insights on dinosaur trackways. John Hubert discussed the stratigraphic location of the Murray Quarry with me and provided unpublished geologic data helping me to locate the Hampden Basalt. Martin Lockley and James Farlow provided thoughtful reviews of the manuscript, which greatly improved it. Finally, I wish to thank Doug Arey, Kathy Proulx, and Paul Vasconcellos for their personal support and friendship. Thank you all.

Notes

* = stride that was determined by multiplying a single pace by two, all other abbreviations as in Appendix 1.