Dr. Don Brinkman, Director of Preservation & Research, Royal Tyrrell Museum of Palaeontology
The Royal Tyrrell Museum undertook two weeks of field work in Dinosaur Provincial Park in the summer of 2013. Our main priority was to collect a hadrosaur skull discovered in 2012, complete with teeth still intact in the lower jaw. From these teeth, we could tell this was a member of the Lambeosaurinae sub-family, which are the crested members of the larger Hadrosauridae family, popularly known as the 'duck-billed' dinosaurs. While skulls of lambeosaurines are always significant, this one was particularly noteworthy because it was located in the Lethbridge Coal Zone, from the uppermost and younger rock layers of the park. In recent years, we recognized there is a sequence of species present in the formations exposed in the park. The lambeosaurine species known to occur in the Lethbridge Coal Zone is Lambeosaurus magnacristatus. So another specimen of lambeosaurine from this zone would help document this pattern.
Recovering the skull took about a week. To collect the specimen, we first removed the overlying rock right down to the layer of the specimen to see where it was lying. In this case, the skull was not fully articulated, as several bones had separated from each other, but were concentrated in a small area. Once we determined where the skull bones were, we trenched around the area to isolate the skull and promote water drainage. We then covered the specimen and a buffer zone of rock with layers of plaster and burlap to begin forming a protective field jacket. For a specimen of this size, about eight layers were used. To strengthen the jacket, a few 2" x 4" wooden beams were incorporated into its structure. After the plaster dried, the block containing the skull was flipped over. Excess rock was removed and the underside was plastered with the same number of layers, so the jacket now fully encased the specimen. The resulting block weighed about 200 kg and required several crew members to mount it onto a sled and drag it to a site for loading onto a truck for transport to Drumheller.
The next phase will be in our prep lab and might not occur for several months, depending on the priority assigned to the specimen. Circular saws will open the jacket and then the meticulous work separating the skull from the surrounding rock matrix will begin. Cleaning and repairing broken pieces will also require the close attention of our skilled technicians. Once the skull is fully freed from the matrix, we will examine and record all aspects of its external and internal structure to identify this individual. Whatever it turns out to be, it is clear this specimen will be a very interesting discovery.
During the summer of 2014, the Royal Tyrrell Museum will again be active in Dinosaur Park. Our primary objective is to excavate a bonebed containing the remains of the ceratopsian Centrosaurus apertus. We hope information generated by this material will help demonstrate the pattern of biology for this diverse family of dinosaurs.