Dr. Don Brinkman, Director of Preservation & Research, Royal Tyrrell Museum of Palaeontology
During the 2012 field season, a number of projects were undertaken in Dinosaur Provincial Park. Surveys of the park continued, and the effects of the heavy rains over the past couple of years could be seen with new specimens being exposed.
Three complete turtle shells were found. Each was intact because only a small portion of the shell had been exposed. One was the small soft-shelled turtle Aspideretoides foveatus, perhaps the most abundant turtle species in the park with a shell rarely exceeding 30 cm long. The other two were the medium-sized baenid Plesiobaena antiqua, likely the second most common turtle of the time. These were found in areas that were frequently visited so were only exposed by erosion in the past few years.
On the last day of field work, a potentially exciting hadrosaur was located. This specimen is disarticulated but the elements exposed on the surface included parts of the skull and a lower jaw with teeth, as well as vertebrae and ribs. Having a skull associated with the rest of the skeleton is interesting enough but this specimen is especially noteworthy because it is in the uppermost beds of the Dinosaur Park Formation, the unit often referred to as the Lethbridge Coal Zone (LCZ). This is significant because evidence indicates LCZ dinosaurs are different from the kinds that occur lower down in older layers, and this specimen may help to confirm that. Since this discovery occurred at the close of the field season, we couldn't start excavation this year but it will be high on our "must do" list in 2013.
Another focus of field work was a survey of bonebeds to get information that would help direct the ongoing study of bonebeds in the park. A number of individual sites were mapped and the diversity and abundance of fossil resources documented. This information will enable us to decide which bonebeds need priority attention as part of the Dinosaur Park Guided Excavation program.
In addition to paleontological work, Dr. David Eberth, Curator of Sedimentary Geology at the museum, undertook a series of studies of the sedimentology of the park. The key goals of this research are: to determine the size and behavior of ancient river channels that flowed through the area 76 million years ago; to map the location of the Bearpaw Sea and its changing shorelines during the late Cretaceous Period; and to investigate the ages and environmental preferences of the many different species of horned dinosaurs (ceratopsians) that once lived in this area.
Dave's project will help us understand how tropical storms influenced the park's ancient landscapes, how dinosaurs were preserved, and the factors that drove high rates of evolution among dinosaur species found here.
The primary objectives for the museum's 2013 season in Dinosaur Provincial Park are to collect the 2012 hadrosaur skeleton, to continue surveying bonebeds, and to look in detail at the pattern of occurrence of dinosaurs and changes in dinosaur populations through the bonebeds preserved in the park.