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Excavation

We have collected data on over 200 turtle fossils at Toadstool Park. Many of these will be excavated in order to study them in the laboratory.

A few shell bones are all that is exposed. We are expecting a small turtle.
Mudstone is carefully chipped away. The turtle is bigger than we expected.
Much bigger. The horizontal extent of the shell is reached, but it is difficult to determine how deep it extends.
We excavate to a depth which we feel is well below all fossil fragments.
Wet toilet paper is applied to the exposed fossil. This fills gaps, holds loose fragments, and protects the specimen from the plaster.
Strips of burlap saturated with plaster have been applied.
The plaster hardens quickly. This old and fragile turtle has a new protective shell.
We carefully excavate below the fossil until there is only a small column of mudstone supporting the specimen. It's looks like a mushroom in a hole.
We prepare to tip it out. The fossil should remain intact with no fragments left behind in the host rock.  
Success. There are no pieces of the fossil exposed. The fossil is completely encapsulated.
After more mudstone is pulled away to reduce the weight, strips of burlap soaked in plaster are applied to the bottom.  
Voila! This big old turtle is now wearing its "field jacket" which will keep it safe for the trip to the lab. It might remain in that plaster jacket for years before being studied. But, had it remained in the field, it would have been susceptible to theft by fossil poachers or destruction by the elements in Toadstool Park's rapidly eroding landscape.
We put the specimen into a large burlap bag to carry it out of the park.
The scientists restore the site.
This turtle is taking its first walk in 31 million years.

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