Fossil of the week: 5/29/09

This past week I was attending the 8th Conference on Fossil Resources in St. George, UT. The second group of talks all focused on the Campanian aged flora and fauna of the western interior. A few brief mentions of the poor neglected duckbill dinosaur fauna were made, but I wanted to share with you an image of one that I'd love to find: "The duckbill that ate Manhattan!" Paleo Tech Jacob Jett (6'4" tall, shown back in his younger days) is shown for scale.

This isolated rib bone was discovered in the upper Judith River Formation (Campanian aged) in the summer of 2004 while excavating a centrosaurine horned dinosaur called "UTC". Isolated duckbill skeletal remains are not uncommon at dig sites. In fact, juvenile hadrosaur jaws have been found at both our  "Joyce" and "Pete 3" sites in the same area.

Unfortunately, isolated postcranial remains on hadrosaurs aren't very diagnostic, so it is impossible to say which critter this rib belongs to. It is a good deal longer than our longest rib on "Big Ed", the 34 foot long Edmontosaurus annectens that is now on display in Korea. I'd estimate the body length of this duckbill to be at least 40 feet.

Fossil of the week 5/14/09

In honor of this week's late update, I present to you "Holly" RMDRC 09-007, a pterosaur from the lower Niobrara Chalk of western Kansas. It's only fitting, since the excavation of this specimen is the reason this week's update was so late. confirmation of the genus waits on further prep work, though we have a pretty good idea what it is.

I discovered this specimen Monday morning while scouting on a private ranch. Excavation took about a day, and the entire specimen (including the rarely preserved skull) is back in our lab now. The blocks contain most of the body and wings as well as the rear portion of the lower jaws. Preparation will commence as soon as I get back from a small spurt of paleo conferences over the next few weeks.

Pterosaur remains are not uncommon  in the Niobrara, even though our dig sites are several hundred miles away from the nearest shore. Pterosaurs were strong flyers, and appeared to spend quite a lot of time hunting over the open ocean. The males had elaborate crests, most likely to attract females, just like their very distant cousins today!

Fossil of the Week 5/2/09

For this week's dinosaur, we venture up to Montana and the Judith River Formation, 75 million years ago in the late Cretaceous. Larry, a rancher who loves to hunt for dinosaurs near his home, was exploring badlands with Dr. Kraig Derstler during the summer of 2007. He had just finished wagering Kraig the princely sum of 2 quarters that he could find a diggable dinosaur fossil first when he came across hadrosaur bone fragments weathering out of a very steep slope. A bit of excavation revealed a few bones clustered together, luckily a RMDRC field crew was already en route to Montana, and we would spend the next month at the site.

In the photo, Dr. Kraig Derstler and Paleo Tech Jacob Jett work on breaking up a large sandstone block above the dinosaur (under the white cloth near their feet). Small man-portable jackhammers help tremendously with digs like this.

Most of Joyce (Named after Larry's wife, whoever finds the dinosaur gets to name it) was buried fairly quickly, with only a few shed tyrannosaur teeth in the quarry indicating limited scavenging activity. Unfortunately, not long after Joyce was buried, a small creek had cut through the site removing most of the tail. Somehow knowing it had been missing for 75 million years made us feel a bit better. From the limbs, vertebrae and skull were were able to tell that it was a lambeosaurine duckbill dinosaur, one of the types with a head crest. The pile of bones was so extensive that we had to remove most of it in one large jacket, and slide it up nearly 50 feet of slope to load on a trailer. Preparation is ongoing, and we hope to have some bones on display in the coming months.

Joyce made her television debut in 2007 as well, with NBC Nightly News and ABC (Australia) both having camera crews visit us at the dig site.

Mosasaur Summmer Video Online

The video of our 2007 field season is up and on Youtube. Enjoy!

Fossil of the week: 4/28/09

Back to the exciting marine reptiles! This week is "Ono", a very large but headles Platecarpus ictericus that was recovered in 2006. Surprisingly, Ono is not named in honor of the wife of a former Beatle. Here's the story:

Our field crew had just left an area called "The Forbidden zone" because our owner, Mike Triebold, had decided we had found too many specimens in that small spot. This sometimes happens in the Niobrara. We instead headed to the nearest outcrops, about 200 yards to the east. While still 25 yards away, Mike tossed his pick to the ground and exclaimed "Oh no, not another mosasaur!" As we approached closer we could see the sides of 6-8 dorsal vertebrae exposed on the outcrop surface. Back in the lab we prepared the specimen and remarked at the articulated ribs, as well as probable cartilage in between the ischia (pelvic bones).

Ono is a very strange case, as headless articulated torsos are nearly unheard of in the chalk. This mystery made us do some "digging" ont he internet, and we discovered that we were working not far from Cope's 1871 expedition camp site. There is a possibility that the missing skull may have been collected 130 years prior!

Fossil of the Week 4/20/09

Back on the dinosaur side of things, we're working on a very large Triceratops skull. This unnamed skull was discovered in 1999 by Mike Triebold in Harding County, SD, and has been taking up a lot of room in storage ever since. We opened the jacket at the end of March and have been working at it in small increments ever since. There is a large area of ironstone concretion on this, the down side, making preparation difficult and time consuming. Once cleaned and stabilized, we'll rotate the jacket upright and work on the other side, hoping to have a 3d skull mounted in a few months. As you can see, it is missing its beak, lower jaws and a portion of frill. These items will be restored later with plastic and epoxy putty.

The interesting things about this skull is the morphology preserved. It has a relatively large nasal horn, yet short and fat browhorns. There is a high degree of variation known in Triceratops, primarily because there are more skulls known than skeletons. In fact, Triceratops skulls are among the most common dinosaur fossils discovered in the Hell Creek Formation. This is the exact opposite of how we find other dinosaurs.

Pete 3 Update

Preparation is going strong on some of the larger jackets, which has the added benefit of freeing up space in the lab for other things! Here's the left ilium, with a total length of 1115mm. The bone is still very soft and fragmented. The only really well preserved parts tend to be the toes and legs. The object to the top of the jacket is a cervical vertebra, which we will separate from the ilium once this side is prepared and we can rejacket and roll the bones. Then it will be restoration (primarily crack filling) and molding time, which can be very challenging.

These larger jackets are chock full of surprises. Due to the softness of the matrix and bone we were not able to fully excavate or identify the individual elements in the blocks. Now in the lab we are finding that this dinosaur is much more complete than we originally believed.