Mission Jurassic fossil excavation and preparation
Although they have turned to stone, fossilized bones are fragile. Excavating them is a painstaking and precise process to both preserve the specimen and document any clues or additional information provided at the site, such as (for example) soft tissue remnants. Once the fossil is out of the ground and back at the Paleo Prep Lab, it can provide important information about the life and behavior of a particular animal, including evidence of disease or injury.
Tools of the Trade
Paleontologists use a wide variety of tools in both the field and the lab. At the dig site, they use everything from soft toothbrushes to specialized pneumatics (air-powered) tools, like airscribes—a type of pneumatic “jackhammer” tool that can separate small amounts of the matrix (surrounding rock) from the fossil. In addition, a wide variety of glues are used to keep fossils in one piece.
It is important to track the types of fossils found and where they are found. Each fossil is issued a field number, which is used to keep track of what is excavated by year. Paleontologists also make detailed maps showing how each bone was found in the ground. This information is used to determine the taphonomy of the site—the processes of burial, decay, and preservation that allowed the remains to become fossilized.
Preparation for Shipment
At The Jurassic Mile site there are many white packages on the ground. These are fossils in their field jackets, which are used to keep them safe on the long journey back to the museum. Field jackets are burlap strips dipped in plaster that are then wrapped around the fossils, but first aluminum foil is wrapped around the fossil to make sure it doesn’t contact the plaster. Paleontologists also leave a good deal of the rock on the fossil, which helps cushion the fossil within its jacket. The rock will be carefully removed in the lab.
Detailed work starts when the jackets come back to the Paleo Prep Lab at The Children’s Museum. Museum paleontologists open the jackets and work deliberately to clean, fix, and stabilize the fossils. All of this work is carefully documented, complete with pictures and prep sheets. Sometimes fossils are molded to make copies for education or to send to other museums. Once the prep work is complete, the fossils live out their afterlife on display or in collections storage, where they are used for education and research.