An Early Cretaceous (Berriasian) fossil-bearing locality from the Rocky Mountains of Alberta, yielding the oldest dinosaur skeletal remains from western Canada

Western North America preserves iconic dinosaur faunas from the Upper Jurassic and Upper Cretaceous, but this record is interrupted by an approximately 20 Myr gap with essentially no terrestrial vertebrate fossil localities. This poorly-sampled interval is nonetheless important because it is thought to include a possible mass extinction, the origin of orogenic controls on dinosaur spatial distribution, and the origin of important Upper Cretaceous dinosaur taxa. Therefore, dinosaur-bearing rocks from this interval are of particular interest to vertebrate palaeontologists. In this study, we report on one such locality from Highwood Pass, Alberta. This locality has yielded a multitaxic assemblage, with the most diagnostic material identified so far including ankylosaurian osteoderms and a turtle plastron element. The fossil horizon lies within the upper part of the Pocaterra Creek Member (PCM) of the Cadomin Formation (Blairmore Group). The fossils are assigned as Berriasian (earliest Cretaceous) in age, based on previous palynomorph analyses of the PCM and underlying and overlying strata. The fossils lie within numerous cross-bedded sandstone beds separated by pebble lenses. These sediments are indicative of a relatively high-energy depositional environment, and the distribution of these fossils over multiple beds indicates that they accumulated over multiple events, possibly flash floods. The fossils exhibit a range of surface weathering, having intact-to-heavily-weathered cortices. The presence of definitive dinosaur material from near the Jurassic-Cretaceous boundary of Alberta establishes the oldest record of dinosaur body fossils in western Canada and provides a unique opportunity to study the Early Cretaceous dinosaur faunas of western North America.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author