This series of drawings demonstrates the process of removing a typical large fossil from the field. In this case the fossil is a partial mammoth tusk.
1. The fossil is discovered. Erosion has removed enough surrounding rock or soil to partially expose our fossil.
2. Scientists carefully expose the fossil using a variety of hand tools. They take measurements, record spatial data, and make a map. Although not shown in the drawing, the fossil may be given a protective "cap" of plaster at this point to prevent damage as excavation continues.
3. Paleontologists expose the tusk even further, in preparation for plaster jacketing. Excavators have dug a trench around the fossil and it now sits on a pedestal of rock.
4. Excavators cover the fossil tusk with moistened tissue paper, which will act as a barrier between the fossil and the plaster.
5. Excavators wrap burlap soaked in plaster around the fossil. When dry, the plaster hardens into a shell that protects the fossil during transport.
6. Next, one carefully tunnels under the fossil and quickly flips it off its pedestal. This is usually the most delicate and dangerous part of the excavation.
7. After excavators flip the fossil, they apply plaster burlap strips to the exposed rock matrix to completely encase the fossil. We have successfully made a plaster jacket.
8. After the plaster has hardened, we can prepare our fossil for transport. We can now move the fossil by sling, sled, or, if we are lucky, by vehicle.