We are back again in southern Alberta, to continue our palaeontological survey and excavation of the Milk River region and adjacent areas. This blog will document how this field season progresses, and will report on any new and exciting dinosaur discoveries from the field!
June 28, 2011: Home Sweet Home
This year, I arrived a few days late into field camp. My colleague and collaborator on this project, Dr. Michael Ryan, and ROM technician Ian Morrison had been on the ground for about a week. They had setup our usual campsite in our familiar field, and had started to open up the main quarry of the season. Like last year, the spring had been catastrophically wet, with major floods near Medicine Hat and soaked fields for the farmers around Manyberries, our closest town. Our campsite is surrounded by huge ponds of water where there are typically seeded fields. The ponds are a magnet for bird and amphibians, and the nights are steeped with the sounds of frogs, ducks, and coyotes. Our field season will last another three weeks, and I am looking forward to good year. It’s nice to be back home.
One of our main goals for this year is to prospect for new fossil sites on the south side of the Milk River. We are specifically looking for new sites in the lower Oldman Formation, a series of rocks that represents a poorly known time in the Late Cretaceous sequence in western North America. We were taken to a very promising site by one of our close friends in the area. She had found some associated ceratopsian bones, and thought that it looked like a good prospect for further investigation. As usual, she proved to be right. With several vertebrae and skull bones already exposed, it looked like this would be a productive site worthy of excavation in the coming days. The area was relatively rich in fossils. Shell beds are common and preserved the remains of fresh-water clams and snails.
The major excavation site of this season is the Macpheeters Bonebed, an extremely rich deposit of horned dinosaur bones belonging to an animal called Centrosaurus – just which species of Centrosaurus we don’t yet know. We hope to uncover the key bone of the back of the neck shield, or frill, that has the distinctive arrangement of hooks and spikes that will allow us to identify the species this bonebed belongs to. ROM technician Ian Morrison and Kentaro Chiba, a Japanese colleague who recently finished his Master’s Degree on the taphonomy of the Macpheeters site, are heading up this excavation. We are conducting excavations at the Macpheeters Bonebed site for the third consecutive year, and it is surprising that we still haven’t uncovered a good parietal bone – we have found pretty much everything else in abundance. In the first week of work, Ian, Kentaro and their crew have already uncovered five squamosals, the other bone that forms the frill in ceratopsian dinosaurs. We have also uncovered this partial skull, consisting of the bones surrounding the eye, including the characteristic low brown horn.
Every year, I run an undergraduate field course through the University of Toronto Research Opportunity Program that deals with field and lab techniques in vertebrate paleontology. The students first spend two weeks preparing bones in the ROM lab, where they get used to working with fossils in controlled conditions, and then they take part in our fieldwork program in Southern Alberta. Today was their first day in the field, and they found a number of nice bones in the bone bed.
Read more about David’s dinosaur adventures in the field and see our Summersaurus Dino series for more on the ROM’s hunt for dinos!