U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT
 
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Excavation Journal

May 8, 2001: Getting Down to Business

Tours of the site have all been completed, and the weather is good, so our paleontologists are getting down to the serious business of excavation this week. Dr. Alan Titus called in to give us an update. Kelly is going back to the site tomorrow (Thursday) to shoot some more pictures which we will share as soon as we get them.

The excavation crew this week is down to two people. (This is not the only work being done on the Plateau. Our team of paleontologists is also spending the summer looking for new fossils.) Dr. David Gillete and Merle Graffam are on the site working continuously through daylight hours to get as much done as possible.

Crew Down to Two: Merle Graffam (left) and Dr. Dave Gillette (right) digging at the site. The excavation will take longer than anticipated due to the exceptionally hard rock they have encountered.

These chevrons (rib-like bones) are removed separately during excavation.

PHOTOS BY KELLY RIGBY

So far, they have removed the chevrons from the tail. Chevrons are the rib-like bones projecting downward from the vertebrae. They also have started plastering the tip of the tail.

Dr. Gillette uses a paintbrush to clean the fossil before plaster is applied.

Isolating a piece of the tail. Notice the small numbers written on each section. This will assist in putting the tail back together in the lab.

I did not realize that different phases of an excavation can be going on all at the same time. While the tip of the tail is being plastered and removed, trenches are still being dug around the larger sections. These will be plastered later.

The basic method of plastering fossils for transportation to the lab was developed more than 100 years ago. Scientists dig a trench around the fossil, keeping it intact with the surrounding material (rock or debris–paleontologists call this the matrix.). Sections of the fossil are isolated. This may require breaking the fossil into manageable pieces if the fossil is large. Dr. Titus explained that fossils tend to come apart at natural breaking points —at the joints, for example.

If the section is large, they dig around and under it until it is sitting on a “pedestal” of earth – This is called pedestaling. They then cover the section with plaster of Paris, and wrap it in burlap to hold it all together. They remove it from its “pedestal“ and plaster and wrap the underside. This protects the fossil while it is being transported to the lab. The lab is where the most detailed study of fossils is made (not in the field). This part of the project will be the focus of our October broadcast.

Still working. Merle uses gloves to protect his hands.

Bare hands are sometimes the best tools – here used to apply plaster. That must feel good after all that hard physical labor! Plaster is applied to protect the fragile fossils for transport to the lab.

While burlap is typically used, Dr. Titus explained that since the pieces being plastered are relatively small, it is easier to use medical bandaging– the kind used for setting casts. (If you’ve ever broken one of your own bones, you know the stuff we’re talking about!) This is another example of using materials and tools developed for other purposes. In many cases, innovation and perhaps more often —improvisation —are keys to the success of field work.

Toilet paper? No, this is the medical bandaging they use to wrap and protect the bones after they have been plastered.

Dr. Dave Gillette and Merle Graffam plaster a section of tail. Hats are essential in the intense sun of the Kaiparowits Plateau!

The plaster blocks now being prepared are less than 2 square feet. In addition to starting to isolate and wrap the smaller pieces, they have deepened the trenches they have dug around the entire specimen to about 8 inches. Eventually they will dig deeper and under the fossil in order to plaster and wrap the larger pieces. These larger pieces may be in excess of 3 square feet. As the pieces get larger —and heavier —they will use the larger more traditional burlap pieces to wrap the plaster. In the process, they continue to look carefully for any new bone fossils, but so far, they have not discovered any new pieces of this specimen.

But they did make an amazing discovery about 100 yards from the site. Dr. Titus was looking around and found a piece of bone exposed on the ground. He swept away the debris from the bone and found that he had discovered what appears to be a 14 inch long bone articulated (connected) to another bone. This is a small to mid-sized dinosaur bone. Dr. Titus says he suspects it is a foreleg or forearm. Further study will be necessary.

This is another example of how scientifically important the Plateau is. Based on what paleontologists already have found, they suspect there must be many more important fossils remaining to be discovered on the Kaiparowits Plateau!

In fact, Dr. Titus says that their team of paleontologists will be spending the whole summer not just looking for fossils, but also doing “surface collections” of fossils they find on the ground. This means the fossil is less than a square meter in size and less then 16 inches deep. For this, they have been given a special Surface Collection Permit. If it is larger or deeper than that, other special permits will be required. He thinks these activities will keep the scientists busy all summer. Hopefully, they will find more important fossils.

Still working...

This discovery also brings up another important point. I asked Dr. Titus if anyone can just look for and take dinosaur fossils from the Monument area, since there seem to be so many. He said that, first of all, it is illegal to collect vertebrate fossils! You need a permit to collect them, or other artifacts, off the public lands. (In some cases, it is O.K. to take invertebrate fossils —but you should always check with the land owner or land manager. Different places have different rules.)

But just as important, taking fossils is like taking pieces of a puzzle away from scientists. Fossils can tell us many things – not just the size or age of a dinosaur, but also they can tell us about what the environment might have been like during that time, how the dinosaur lived (say, if you found a dinosaur nest or groups of similar – or dissimilar —dinosaurs together). There is still a lot to learn about the age of dinosaurs, and taking fossils takes millions of years of history out of the picture.

So what should you do if you find a dinosaur fossil? Dr. Titus suggests that you report it to the land manager, park ranger or any scientists working in the area. Make sure you follow up on your discovery. You could become famous if the find is an important one! You could even have a dinosaur named after you.

That's all I have to report for today. We will post new pictures of the excavation as soon as we get them from the field.

–Elizabeth


 
Last updated: 10-23-2009