Sunday, July 26, 2009

Lori's Ghost Ranch Bones



I'm working on some new (to us) material from the Hayden Quarry at Ghost Ranch, New Mexico. The cast has carbonized wood and bones from several individuals (presumably phytosaurs and aetosaurs) in a crumbly matrix. There are some aetosaur scutes, some small limb bones, and a couple of verts in some foil wrapped packets stuffed into the cast. These pieces have needed mostly cleaning and glueing. The nicely curved limb on the left is about 80cm long and appears to have some fossilization of cartilage on the distal ends.

—Lori

Thursday, July 16, 2009

Nothronychus graffami, the float and bloat Therazinosaur


Salt Lake Tribune article:

http://www.sltrib.com/news/ci_12848095

Several UMNH volunteers including me have done prep work on Nothronychus graffami. The fossil was found in deep marine sediment (the Tropic Shale) and the bones were flattened, presumably under pressure of their unusual burial. It's thought that this critter was swept to sea from near the shoreline, or died on land or in a river and the bloated carcass was washed out far offshore where it "popped" and sank. The article mentions work on a pleisiosaur near this find.

Here's a very interesting pdf with detail about the find, along with nice illustrations from the Arizona Geological Survey:

http://www.azgs.state.az.us/Summer_07.pdf

As a byproduct of my volunteer prep work, I'm now much more skeptical of what a "mounted specimen" means. Nothronychus graffami, for example, was missing its head and most of the bones were so badly deformed that no casts could be made that remotely resemble the mount that Gaston Design in Grand Junction, Colorado created. As I recall, the claws were in the best shape for casting and they're likely the least reconstructed pieces, but most of the mount would have been sculpted and not cast directly from the bones. The skull and presumed style of tooth would be scaled from specimens of related species. I doubt many visitors viewing the mount will understand the (highly) educated estimates and artistic skill that went into the recreation.

-BJ


Tuesday, June 30, 2009

On the B side.


Limb bones on the opposite side of my working specimen.

— BJ

Tuesday, June 16, 2009

Little Limbs — BJ's Current Specimen


I've been working on this specimen over a few months now, averaging 2.5 hours a week on Sunday afternoons in the UMNH prep lab. When I got this piece, the main outlines of the limbs on both sides of this specimen had been roughly exposed by someone else. I've exposed some additional bones and I'm currently working with a micro scribe under a low power stereo microscope to remove matrix and a rough crust that obscures bone detail. The matrix is quite hard, which is why I'm using an air tool on such a small specimen. The longest bone in the photo is approximately 10 cm long. There's another pair of long bones on the opposite side of this specimen. I'll get a photo of that side next Sunday.

As I recall when I got the specimen to work on, these are thought to be dromaeosaur hind limbs. I'm guessing that some of the new bone I've exposed is pelvis or pubis. I'm often surprised at how paleontologists can correctly identify bones that are barely visible, but on occasion the preparation reveals something unexpected.

-BJ Nicholls

Wednesday, May 13, 2009

Utah Friends of Paleontology (UFOP) Annual Meeting

(From Martha Hayden, UFOP State Office)

The 2009 Utah Friends of Paleontology Statewide Annual Meeting will be held in St. George, Utah on Thursday, May 21st, in conjunction with two professional meetings: the 8th Conference on Fossil Resources-Partners in Paleontology (8CFR) on May 19-21, and the Grand Staircase-Escalante National Monument Cretaceous Conference-Advances in Western Interior Late Cretaceous Paleontology and Geology on May 22-24.

The UFOP Annual Meeting will be held at 7:00 pm on Thursday May 21st at the St. George Dinosaur Discovery Site at Johnson Farm, 2180 East Riverside Drive, St. George, Utah. Following our general membership meeting, a talk will be given by Randy Irmis, the new Curator of Paleontology at the Utah Museum of Natural History. The title of his talk is: Discovering Dinosaurs in the Horn of Africa.

The UFOP Annual Meeting is free and open to all, but if you would also like to attend the 8CFR or GSENM Cretaceous Conference, you can still register on-site. Additional details and registration information can be found on the meeting websites:

8th Conference on Fossil Resources:

www.8cfr.org

GSENM Cretaceous Conference:

http://www.learningfromtheland.org/cretaceousconference/

(Active links below in previous blog post)

Cretacious Conference Links

Grand Staircase-Escalante National Monument

Cretaceous Conference

Advances in Western Interior Late Cretaceous Paleontology and Geology

May 22-23, 2009 (with post-meeting field trip on May 24)
The Dixie Center, St. George, Utah

In Conjunction with the
8th Conference on Fossil Resources-Partners in Paleontology
www.8cfr.org

Tuesday, May 12, 2009

High Explosives at Dinosaur Nat. Monument



NPS Photo of Quarry Visitor's Center, Closed since 2006 for safety reasons.

(AP news via KSL TV's website)

At a site not far from Dinosaur National Monument's Quarry Visitor Center, explosives specialists blasted away a hard stone layer to reveal new fossils. The lesser-known DNM 16 quarry has been productive but the hard stone has stymied new fossil finds since 2007.

Link to article.

Monday, May 11, 2009

From the UMNH Lab


What's on the slab in the lab, May 9.

2009 UMNH Paleo Field Plans

(From Mike Getty, Utah Museum of Natural History Collections Manager)

Hello Everyone,

I am pleased to announce the UMNH paleontology field plans for 2009.

We are planning on our field season this year in Grand Staircase Escalante National Monument (GSENM), on the following schedule:

May 13-21 Tyrannosaur Dig and Wahweap Reconnaissance

May 24-26 Field Training
Note this is from Sunday to Tuesday this year due to scheduling conflict. We will be in camp until approximately the 28th for those who want to stay longer. Those people interested in joining us for the field training should also view the attached information sheet for specific information about the training.

August 1-September 18 (approximately) Main Field Season
Kaiparowits and Wahweap formations.

During this time we will be conducting both excavation of existing localities, and prospecting for new fossil localities in both the Kaiparowits plateau of GSENM. We plan to begin the season with the preliminary excavation of an associated tyrannosaur discovered this winter in the Wahweap formation. In August, we will be back in our Horse Mountain camp in the Kaiparowits (where we have mostly worked out of for the past two seasons), where we will resume excavations on the large "Horse Mountain Gryposaur" which we began last season. In August through September, we will also be spending considerable time prospecting for new localities in both the Late Cretaceous Wahweap and Kaiparowits formations.

We are currently looking for volunteers for the field season and can typically provide transportation to and from the field site for participants who can get themselves to Salt Lake City and are planning to stay for a minimum of two weeks. There is no minimum time limit for people providing their own transportation, but given the distance from Salt Lake City, we recommend people to plan for a minimum of three days. Please keep in mind that working in Grand Staircase can often involve long strenuous hikes over difficult terrain, so you must be over 18 years old and in good physical condition to participate. The only cost to participants is a $20 dollar/day contribution to camp food, which is prepared collectively by staff and volunteers. There are fee waivers available for qualified students and long-term volunteers. If you are interested in joining us, please let me know the dates you are interested and I will provide direct communication on specific details of camp locations and what to bring etc.

We are also planning several additional trips this season to other areas of Utah, including the Mastrichtian aged North Horn formation; the Triassic Chinle formation and the Permian Cutler formation, which will involve several shorter trips through June and July. Camp times and locations are yet to be determined, so if you are interested in joining us during this time, you should let me know and we will provide more specific details, on camp times and locations.

Anyone interested in joining us for any of these projects should contact Mike Getty at mgetty@umnh.utah.edu, or by phone at 801 834-3357 and those people specifically interested in the field training on the memorial day weekend should read the attachment and please contact Mike or Debbie to sign up as soon as possible, as there is limited enrollment. We will contact people to confirm their participation as soon as possible.

Sincerely,

Mike Getty,
Collections Manager, Paleontology
Utah Museum of Natural History

Field Training 2009 PDF