Sunday, July 31, 2011

Wapiti River fieldwork, part 1

Hi everyone! It's been a while since my last post as I catch up on research and get ready for a brief stint of fieldwork in Grande Prairie. I've been working at the Wapiti River bonebed for the last few days, where we are excavating a Pachyrhinosaurus bonebed. Here is a quick update of what we've been up to.

The bonebed is on a steep river side, and we have cut a long but narrow ledge into the cliff. The view is quite spectacular and we occasionally see deer and bears on the other side of the river. 

Ropes are helpful for getting up and down the steep cliff!

The bonebed includes two distinct preservational types - hard bones that separate well from twisty shaley mudstones, and hard, hard nodules containing mostly skull bones. You can see the skull nodules below Angelica, as she works in the mudstone layer.

It can be rather goopy in the quarry and the bones are often cracked with mud in between the pieces, so we often map the bone and then remove it completely to clean and glue before we jacket for transport. The bones look quite good once they are clean and put back together! I am pointing at a skull element I found on my first day here.

More to come soon!

Wednesday, July 6, 2011

You know field season is well underway when... of the prep labs already looks like this!

These dark grey bones are this year's harvest of hadrosaur material from the Danek bonebed located within the city of Edmonton. The U of A offers a fourth-year vertebrate palaeontology field course (PALEO 400), which for the last several years has taken place at this bonebed. It's an excellent locality as students can return home in the evening, it is easy to access, the matrix is comparatively soft and the bones are comparatively hard. Each student participates in three weeks of fieldwork and will do either a research paper or talk based on the bonebed.

The bonebed has only been described in a few conference abstracts so far, so I won't say too much about it. I can say that we have collected quite a lot of material, and it is pretty neat to have a dinosaur bonebed right within a large city. We have excavated an area adjacent to a creek, and it is a very nice spot to sit and dig all day. I did not make it out this year because of travel, but here are a few photos from the first year we worked this site, 2007.

The bonebed is quite photogenic and several times local news have come to the site to do stories (we even made it onto the National one time). The density may not be as great as some of the ceratopsian bonebeds in Alberta like the Pipestone Creek Pachyrhinosaurus bonebed, but there are still a lot of bones in the relatively small areas we have excavated.

Now I did just say that the bonebed is a very pleasant place to work...except for when it snows. Yes, this is what the bonebed looked like during the 2010 field school, which was held in MAY. The students dutifully shoveled snow before shoveling dirt...

Dinosaur bones can also be encountered in the North Saskatchewan River valley, but generally only as very scrappy fragments. Last fall hadrosaur and tyrannosaur bits were discovered during excavations for a new sewer, which I discussed in the Edmonton's Sewersaurus post. From what I understand, the preservation is similar to what we find at the Danek bonebed. I would bet that there's a good chance if you dug deep enough pretty much anywhere in Edmonton, you'd find dinosaur bones.

Friday, July 1, 2011

Stegoceras is everywhere!

And by everywhere, I mean in two PLoS ONE papers this week. (But that's pretty good!) Stegoceras is the focus of a study on cranial ontogeny in pachycephalosaur skulls, and in head-butting in pachycephalosaurs and artiodactyls.

I've always thought of Stegoceras as an unofficial mascot for dinosaur palaeontology at the University of Alberta. The best Stegoceras skeleton ever collected is UALVP 2 (that's right, 2! 1 UALVP 1 is a turtle), shown here on display in our museum in the Earth Sciences Building. The actual recovered bones are displayed below the mounted skeleton. It's a beautiful skull, and pachycephalosaur postcranial material is extremely rare. 

Stegoceras makes an appearance at lots of museums all over North America. Before this corner of the Royal Tyrrell Museum was converted into the new ceratopsian exhibit, it featured a diorama including a fleshed out Albertosaurus, Edmontonia, and Stegoceras.

You can still see these two Stegoceras skeletons at the Tyrrell.

I even saw the UALVP 2 Stegoceras skull at the Smithsonian last May - can you spot him in this who's who of pachycephalosaurs?

Read all about Stegoceras in these new papers:

Schott RK, Evans DC, Goodwin MB, Horner JR, Brown CM, Longrich NR. 2011. Cranial ontogeny in Stegoceras validum (Dinosauria: Pachycephalosauria): a quantitative model of pachycephalosaur dome growth and variation. PLoS ONE 6(6): e21092.