What is it really like to collect vertebrate fossils?
Hopefully this Web exhibit will give you some idea. It illustrates a trip made by UCMP scientists to Eastern Montana from mid-July to mid-August, 1996. We visited the area around Fort Peck Reservoir, where the Cretaceous Hell Creek Formation and the Paleocene Tullock Formation crop out.
What were we doing out there?
Dr. William Clemens of UCMP and U. C. Berkeley's Department of Integrative Biology, and Dr. Carl Swisher of Berkeley Geochronology Center received collaborative research grants from the National Science Foundation to study the recovery of terrestrial faunas after the large extinction at the Cretaceous-Tertiary Boundary. Gathering data for this study is a two-part process: it requires collecting and documenting fossils, and also finding out their ages.
We used several techniques to find and collect fossils. We crawled on the ground to pick tiny fossils off the surface, we dug up and jacketed a few larger fossils in plaster to carry out of the badlands, and in some places we quarried out chunks of rock and dissolved them in water, recovering the small fossils in a fine screen.
We also employed different techniques to establish the ages of the sites which produced fossils. We measured the beds in the Tullock Formation using a staff and pocket transit, and described the different types of rock. We took many samples of rock to use in determining the orientation of Earth's magnetic field at the time the rock was still mud, which will help us establish magnetostratigraphy. A little while after this trip, Dr. Swisher visited the area and also sampled ash beds, which contain crystals that allow us to get radiometric dates.
What kind of fossils did we find?
The kind of fossils we were looking for are called microvertebrates, and they included teeth and other bits and pieces of therian mammals, multituberculate mammals, lizards, salamanders, frogs, birds, fish, turtles, crocodylians, and champsosaurs. Since we mostly found fossils in ancient stream channels, the different animals had been broken into pieces and mixed together.
Exactly who got to go on this trip?
Four of us from the Clemens Lab at U. C. Berkeley went into the field, where we met up with Dr. Don Lofgren and members of the Peccary Society from the Webb School, Barry Albright, who was then a graduate student at U. C. Riverside, and Harley Garbani, an avocational collector from Southern California.
Of all these people, I (Anne, from Berkeley) got to document the trip on film, which I enjoyed mostly because I hate having my own picture taken, and this duty kept me behind the camera. I also got to create this exhibit! Hope you like it.