Rex Bones

most interested in the beer and the horseshoes.

In the daytime I was rarely around to see what was doing. Instead, I was off walking around looking for more fossils, making maps and notes. Prospecting is not always productive, and sometimes it's dangerous. Once, looking out for fossils and not where I was going, I caught my heel going down a slope and tumbled and slid a good fifty feet. Less than a mile from the site I did come on two Triceratops horns, but the rest of the skull wasn't much to look at. We also found a champsosaur (a four-foot long aquatic lizard of T. rex's time) worth collecting.

Meanwhile, Pat and his crew were removing at least fifty tons, and probably more like eighty tons, of sandstone, using ten-, thirty-, and sixty-five-pound jackhammers, along with Bob's crowbar to peel away big sandstone blocks. Everyone pitched in to roll these boulders down the hill. We even got help from Bob Sloan, a mammal paleontologist from the University of Minnesota who's been working the Hell Creek Formation for decades. The scraps were shoveled into buck ets and hauled to the edge, then tossed over.

The crew had to take down most of the hillside to get at T. rex:. By the time they were done excavating, the pit itself was about forty-five feet across and twenty-seven feet into the hill, and they'd dug down about twelve feet into the hill. It took about twelve days of hard work to get all that rock out.

As Pat's crew got through this overburden and close to the layer of sediment where they'd found parts of the skeleton the year before, they switched to smaller and smaller tools—picks and hammers, then awls and trowels, and finally small brushes.

As the brown bone was exposed, it was soaked with squirts from a detergent bottle filled with Vinac. The smelly liquid not only hardens the bone, it makes the bone shiny. Often, even after it has been treated with Vinac, bone will be soft, spongy, and crumbly. We try to handle it as litde as possible in the field, since even the moisture from our hands can make it deteriorate. The matrix, the rock that surrounds it, can present just the opposite problem. Ironstone—or in the case of Kathy's T. rex, hard sandstone—can be hell to dig through. Fortunately the sandstone immediately around the bones was not as dense as in the overburden. And this T. rex's bones were in pretty good shape, with the exception of the exposed arm and

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