Now that I’ve been back from hunting dinosaurs with Project Exploration for a few days, I owe you all the report. I’m not going to go into all of the background, as that was covered pretty well in my blog posts about the 2004 trip, Dinosaur Report I and Dinosaur Report II. So this will just be a little photo-essay about the heavy lifting that was specific to this trip.
During the previous two trips I had been on with Project Exploration, the focus was on prospecting and the early stages of bringing fossils out of the ground. Clearing away the dirt, exposing bone, determining what we found, estimating the physical extent of the fossils. The eventual goal, of course, is to clear away everything but the bones and enough rock (called “matrix” in paleo-speak) to hold it together, wrap up the pieces snugly in wood and plaster (“jacketing”), and bring it all back home — in this case, Paul Sereno’s lab at the University of Chicago. But the process as a whole takes time, and three days of work by a crew of enthusiastic but untutored amateurs generally isn’t going to make it happen. But on this trip we were working on a site where most of the work had been done, and our task was to finish the job. In fact, we were back to the site I had gone to in 2005. In the meantime the locations of the various bones had been ascertained, many of them had been fully jacketed, and our task was primarily to finish off the biggest pieces. “Finishing off” means completing the jacketing process and transporting the jackets to Billings, Montana, where a freight company would carry them to Chicago.
The story is conveyed better by words than by pictures. Click to get hi-res versions in a new window.
Here is a view of our vans, as seen from the dig site. Each morning we’d get up bright and early to have breakfast at Dirty Annie’s (the finest dining establishment in all of Shell, Wyoming, featuring chokecherry pancakes the size of garbage-can lids). Afterwards we’d head out to the site in two rented vans, the backs of which were filled with all the paleontological necessities: burlap, plaster, water, picks, awls, hammers, GPS units, shovels, trowels, gloves, 2×4’s, buckets, tarps, brushes, kneepads, and sundry snack foods. The vans would bounce over dirt trails to the foot of the hill where the fossils were, and we would all jump out, eager to get our hands dirty. (On at least one occasion, unanticipated logistics forced the crew into drafting a theoretical physicist into van-driving duty. Thankfully, nobody was seriously injured.)
And here is the dig site, as seen from where we parked the vans. Just to the left of center there you can see the plaster around the main group of fossils — jacketing that bad boy and trucking it to Billings was our primary challenge for this trip.
For some reason (too excited by the goings-on, probably) I neglected to take a close-up photo of the main fossil group before we covered it with plaster. But to get the idea, here is a smaller group, this one a collection of vertebrae. In the field, the main goal is to roughly carve out the bone and get it back to the lab in workable condition. On the other hand, you don’t want to make it heavier than it needs to be, so you try to remove as much matrix as you can without sacrificing the structural integrity of the fossil. Once the bone is exposed, you cover it with tinfoil, then wrap it with burlap strips dipped in plaster. Delicate soul that I am, I resisted participating in the plastering at first, but ultimately I realized that everyone else was right, it really was the most fun part of the whole procedure. To make the jacket a bit stronger you can plaster pieces of wood to the whole collection, as seen in the bottom part of the picture.
Here is Paul on the first day, explaining to our intrepid crew of newcomers what we’ll be doing out here. The part of the process for which I was best suited was the delicate work with an awl and a brush, clearing away bits of matrix right up against the bone. Probably I’d be even better suited for the close-up work performed by the preparators back in the lab, who work under microscopes to remove things at the grain-of-sand level and reconstruct the bones. Actually, come to think of it, I’d be best suited to be sequestered in a room far away from any fossils, left with a pen and paper to think about the universe. So that all worked out for the best.
Paul, eager to get going, burns off nervous energy by doing push-ups. (He was the only one to employ that strategy.)
Here is the main collection of fossils, separated out from the surroundings and covered on the top with plaster. It consisted of vertebrae, ribs, and sundry other bones that I won’t pretend I could identify. Paul figured that it was a sort of Diplodocus, one of those lumbering herbivores with giant necks and tails that roamed North America during the Jurassic. But the structure of the hip bones differed from that of the ordinary Diplodocus, so Paul judged that it was a new species. By the second day he had promoted it to a new genus — apparently the rules for whether a new species is in a distinct genus or an entirely new one are a little fuzzy. In any event, our job was to hack away at the underpinnings of this rock, and eventually to bring it home.
And away we go!
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