What We Do
Science Teacher Field Institute
Project Exploration: Summer
Institute
Blog Excerpts from Robin Heyden
Project Exploration is a non-profit science education organization co-founded by paleontologist, Paul Sereno and educator, Gabrielle Lyon. Pearson Education and the family of Dr. Neil Campbell recently made a donation to fund a special Summer Institute program for science teachers. The idea was to get science educators out to the dinosaur-rich badlands of Montana to conduct field work and work with practicing scientists. In July, the inaugural group of "Neil Campbell Fellows" traveled to eastern Montana to participate in a five-day dinosaur dig with Paul, Gabrielle, and other paleontologists and technicians. I was lucky enough to be invited along and the following blog chronicles the adventure. -robin heyden |
 Robin Heyden Photo G. Lyon |
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Dinosaur Dig – Day 2
July 12, 2006
“Rock or bone?”
I can see now why the Montana license plates advertise their state as “Big Sky Country.” As we drove out this morning from Glendive, I scanned the horizon - nothing but open space in all directions. The road tapered ahead to infinity and our white van felt like a ship at sea under all of that sky. The enormous expanse of sky takes up at least three quarters of the view with the most amazing cloud formations - huge puffs that beg to be described. There is space and distance here on a scale not often seen.
Yesterday was my first day in the field. I joined the Project Exploration crew a day into their Summer Institute session (on Day 2), flying into Billings, Montana and then driving three hours due-east to Glendive in the Badlands, near the state border with North Dakota.
The summer institute base is Charley’s Bed & Breakfast Inn, nicely located in Glendive, Montana just one hour from the site. “The site” is a 30,000 acre cattle ranch, ideal for dinosaur digging as it is on the Hell Creek Formation.
What is the Hell Creek Formation?
Indeed, you may well ask. Thanks to our sessions yesterday with expert paleontologists and the boatload of reading we’ve been working through, I think I can actually answer that.
When dinosaurs first appeared on earth, Pangaea was one big landmass. It started to break up during the Mesozoic era with Laurasia (North America and Asia) splitting off and wending its way north and west by the end of the Cretaceous. During the Jurassic, Eastern Montana and the plains of North America were covered by a shallow, inland sea (known as the Colorado Sea).
As the continents shifted, the Rocky Mountains rose, and the polar ice caps formed, that inland sea retreated leaving a swampy shoreline behind in Eastern Montana. This lush, shoreline lasted for only a moment, geologically speaking, but it was during this period of time that the last of the dinosaurs dominated the scene. And, as the sea retreated further and the dinosaurs neared extinction, it turned out to also be a great place to become a fossil.
The silting action of a delta accumulates layers over the dead remains of the dinosaurs fossilizing and preserving them beautifully. Hell Creek is the particular rock formation (a “formation” is a large package of sediments that look similar and contain a particular group of fossils) in which these late Cretaceous dinosaur bones can be found. And Eastern Montana is the perfect spot to find the Hell Creek. The Montana rocks are the right age, with semi arid land, lots of erosion and almost no human habitation or building.
The Lost in Time Ranch, includes land with an abundance of exposed Hell Creek formation. Or, as one of our expert paleontologists, Dave Varricchio, says, “Dang, you’ve got a lot of outcrop here!”
The ranch includes 30,000 square acres. To get to the ranch, you turn off the main road out of Wibaux, onto a dirt road marked “Pine Unit Oil Field”. Eight miles on that dirt road leads you to the ranch’s front door – another, smaller dirt road marked with two uprights and a crossbar of timber. Just like the Ponderosa.
The ranch house is a low-slung affair surrounded by a few out buildings and a big barn. Right now the Ranch is tended by a young man named Jerrod Hagood. He works as a foreman for the Ranch owner, herding cattle, maintaining fences, and generally keeping an eye on things.
We worked here at the B&B in the morning, discussing and deciding on the various teacher portfolio projects, talking about the way to build them, and how they'd work with students.
Hiking Out
At 11:30 we headed out to the site. Lost in Time is only accessible via a 12-mile dirt road. We bounced down smaller dirt access roads on the ranch to get as close as possible to the site. From there we hiked in to a spot where there was outcrop (also known as exposed rock) and did some "prospecting"….which basically means walking around looking for bones.
It's going to take all of us awhile to get good at recognizing bones versus rocks. The rocks have a sedimentary appearance (sort of salt and pepper) whereas with the bones display a characteristic bone pattern – small holes and an osteo-appearance. They also have a different heft to them and a more solid sound when you tap them with a tool.
We hike out in pairs and threes, each team includes a paleontologist or one of Paul Sereno's technical assistants so we can get advice as we move. It’s very difficult to know exactly what we’re looking for and what it is that we find. So the silence of our search is regularly interrupted by the question "Is this rock or bone?"
That first prospecting hike for me was an eye-opener. Is this really the way it’s done? No fancy equipment? No electronic gizmo or new-fangled divining rod to lead us to an ancient bone? We really just wander until we stumble upon something interesting? It appears that paleontology today is pretty much done the way it was a hundred years ago. Patience and sweat. Did I mention that it was 107 degrees out there?
It also prompted me to wonder about the macro versus the micro. Here I was absorbed in scanning the rocks for bone fragments but I realized I also needed to keep my eyes on the horizon, looking at the overall formations, remembering where I was, and where I was headed. This felt like an important skill to develop and something that would come more easily with experience.
After awhile we all got better at recognizing bone fragments. Most of the bones we found were scattered fragments that don’t “go in” (that is, lead to a more complete skeleton). We also spotted some living animals – pronghorn, rabbits, killdeer, sage grouse, indigo buntings, and lots of insects. Plant life is pretty scrubby (this is, after all extremely arid land) – sage and lots of cacti. I could also see the dried remains of what must have been an incredibly beautiful spring flower bloom.
A Triceratops Once Removed
After an hour of prospecting, we got back in the vans and drove to another site. Paul and Gabe had been told by the previous ranch owner that an ex-ranch hand found (and illegally removed) a triceratops skull from this location a few years back. Paul had already staked out the site (in the morning) and, sure enough, they found indications of the removal (hastily and inexpertly done) and other bones from the same organism still there. Just under the first layers of dirt, they found a 1989 newspaper that the perpetrators had used to cover and mark the site. We worked together for two hours to excavate what was still exposed on the surface.
Excavation is painstaking work. The tools are a small pick axe, an awl, and a paintbrush. You carefully poke at the sandstone to crumble it, then brush it away, then poke some more. Always the familiar refrain, "rock or bone?" Bit by bit we started to see the shape of some bones. A scapula, maybe part of a pubic bone. All gargantuan in size. It's really amazing.
After two hours of this, we had carved a trench around the remains and could begin the see the shape of it. We added hardener (water-based polymer) to the exposed bones and then covered the site with a blue tarp and weighted it with rocks.
With the site safely tucked in, we hiked out and headed for dinner at a place called Madhatters - which promises pub, grub, and casinos. And then back to the Charley for showers and sleep.
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Dinosaur Dig – Day 3
July 13, 2006
We started this day with a trip to the Makoshika State Park (Makoshika is a word in the Sioux language that translates to “bad earth”). This is an ideal place to get a feel for the local geology and how it all fits together.
First stop, the Visitor’s Center. In addition to the well-stocked gift store, they have an exhibit that explains the advance and retreat of the inland marine sea and the deposition of the Hell Creek formation. They also have an impressive triceratops skull that was found in the park in 1991. From there we drove into the Park itself – miles of hiking trails through beautiful country, laid out for us like a living geology book.
Makoshika State Park lies at the northwest end of the Cedar Creek anticline, a 20-mile wide by 150-mile long area of uplifted, layered rock. Each look-out spot places you at a breathtaking vantage to see the formations - odd-shaped sandstone knobs, cap rocks, cross bedding, and buttes. You can clearly see the role that wind and water erosion played to form this landscape.
The KT Boundary
At the head of the Diane Gabriel Trail (named after a paleontologist that worked the formation here) we had our first official sighting of the KT boundary. In this photo you can see it as the topmost black band.
Alright now, let’s see if I can take a stab at explaining this! The KT boundary is the marker point between the Cretaceous (K) and the Tertiary (T) periods (roughly 65 million years ago). Since the Cretaceous was the last period of the Mesozoic Era and the Tertiary was the first period of the Cenozoic era, the KT boundary also marks the boundary between eras. These between-era boundaries in the geologic record correspond to times of mass extinctions seen clearly in the fossil record. This particular mass extinction doomed more than half of all marine species and many plant and animal groups, including most of the dinosaurs.
The KT boundary is actually about 1500 cubic kilometers of debris, deposited globally about 65 million years ago. One clue to the Cretaceous mass extinction is the iridium found in the clay of the KT boundary. Since iridium is a very rare earth element but a very abundant meteorite element, the presence of iridium in this boundary layer indicates the extraterrestrial origin of the material. This, in turn, supports the hypothesis that a large asteroid or comet collided with Earth roughly 65 million years ago, forming a huge cloud of debris that could have blocked sunlight and severely disturbed the global climate. This collision and the subsequent fallout, referred to as “the KT event”, changed the environment of our entire planet and altered the course of evolution.
On a lighter note, one can not leave Makoshika State Park without noticing the “Folf” course – no, that’s not a typo. “Folf”, also known as “Frisbee Golf”, is a legitimate sport. It is played on a course of nine or eighteen “holes”, with a tee off point and a gong for each pole. Players fly the frisbee from tee-off to gong, to gong, to gong. They tally their throws for the entire course and the lowest score wins. Who knew?
Shells on land
From Makoshika, we made our way back out to the Ranch and met up with Jerrod. Today we were going to explore an older formation, Bear Paw Shale. Bear Paw Shale is older rock, laid down below (therefore, before) the Hell Creek formation. In it can be found marine invertebrate fossils, inhabitants of the inland seaway that covered much of Montana so many years ago.
We drove out to an area that Paul and Gabrielle had previously marked with their GPS units and began prospecting from a central point. Do you remember how we “prospect? That’s right – we each head out in different directions from a central point, agreeing to meet back at the vehicles within a given period (30 minutes or an hour). Prospecting is really a semi-organized form of wandering while paying attention.
So, off we went. I didn’t take more than 10 steps before I found a rock that looked suspiciously like a shell. I bent over, picked it up, and rolled it in my hand. Sure enough, it was a bivalve fossil! Some distant relation to today’s clam or mussel, deposited at the bottom of an ancient sea during the age of dinosaurs, and here it was – in my hand.
The rest of the prospecting trip was just like that. We all found many fossils – nautiloids, ammonoids (relatives to the modern day nautilus), and bivalves. There they were just lying on the ground! Some were embedded in rocks, some were isolated.
For bad earth, it was a very good day.
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Dinosaur Dig – Day 4
July 14, 2006
Planning and boy scouts
We started out the day with group work on the future of the Project Exploration Summer Institute. Gabe asked for help from the five Neil Campbell fellows thinking through the goals, expected outcomes, the application and recruitment process for the program’s future. As usual, the group of teachers had terrific ideas and came up with very useful suggestions and plans.
From that session we drove out to the ranch to hook up with a group of boy scouts (6th and 7th graders) who had been prospecting with Paul in the morning. We brought them their lunches and heard their stories from the field –
“Wow, it’s HOT out there....do you have any caffeinated soda?”
“We saw bones in the ground!”
“Do you do this every day?”
It was fun to see their enthusiasm and it made us all eager to get out there.
How do you know where you’re going?
After lunch we headed to a new location where Ray had spotted a vertebrae poking out of the ground. He had excavated enough to see that it was a more recent bone, most likely a bison, and to find a long bone nearby. That was enough to make it worth investigating.
Bumping over ruts and trails we got close to the site and then walked in. As we walked to the site, I asked Paul what he does when he is prospecting. I was still mulling over the micro/macro question and was curious to understand what his years in the field had taught him about locating the right sites. He explained that he usually takes a GPS point on his parked vehicle and then heads out. By doing this, he can safely ignore the path he came by and how to get back. This frees him up to pay attention to his forward direction. As he walks, he constantly scans, looking for the right kind of outcrop, checking for sloping rock (as opposed to vertical), while at the same time looking closely for exposed bone or anything out of the ordinary. He walks quickly (I was having trouble keeping up with him) like a man who knows exactly where he is headed. You can almost hear the wheels turning in his brain as he moves.
Global Positioning Systems (GPS) have revolutionized paleontology. It used to be that field workers had to rely completely on their hand compasses, their notes and descriptions of a location. Paul recollected when he found his first significant site in Africa (before the advent of GPS), he very anxious about being able to find it again. He took a compass reading at the road and then set the jeep’s odometer to zero and drove (overland) to the site. He repeated this process a number of times to make sure the reading was accurate. Then he took polaroid shots looking out from the site in all four ordinate directions. He said he kept scanning the horizon, double checking the odometer, looking for landmarks – he was so worried that he wouldn’t be able to get back to it.
There’s no doubt that GPS units are the most significant new tool in the paleontologist’s toolkit. In addition to providing coordinates that others can follow and being able to pinpoint the location of a colleague, they allow you to more loosely prospect a large area. You can head out in a variety of directions; mark likely spots, and then, after you’ve seen a number of possible sites, decide which one is worth going back to.
Going in
Once we got to the new site, Paul explained the significance of what we were seeing. First, and most importantly, the bones are “going in”. That is, as you dig into the section, you find more bone. That indicates that the exposed bone Ray spotted is just the tip of the iceberg and the rest has yet to be unearthed. Next significant indicator, there was a foramen (or hole) in the vertebra which tells us that this is a cervical vertebra. Next point, they found another vertebra, articulated (that is, right next to it, in place) with the exposed first one. This is important because the only way you could find an articulated skeleton in the ground is if this spot was the animal’s final resting place. It died here, was buried here, and hasn’t been disturbed since.
Further evidence for articulation was found with the nearby long bones. As Paul explained, we want this to be a right forelimb. Given the way the skeleton is buried and the lay of the land, we’re more likely to find the rest of the animal buried if this long bone was its right fore limb. By examining the specimen more closely, Paul could see that the radius was on the outside, the ulna on the inside. Therefore (whew), it is the animal’s right forelimb.
So how did they know that this was a bison? We found a long spinal process, near the vertebrae. Bison (and horses) have long spinal processes on their withers. Also, the long bones have growth caps – dinosaurs don’t have growth caps but mammals do. They can also tell that these bones haven’t completely fossilized yet. The bones on this site are what you might call “sub fossils”. They are lighter and younger – most likely somewhere between 200 and 1000 years old. The only way we’ll know for sure is to radiometrically date the bones back at the lab.
But first, we’ve got to get it out of the ground. We started with shovels on the grassy tufts on top. Once we got down to sand, we began with awls, brushes, and scoopers. We removed the top layers of sand and dug around the edges, to determine the perimeter of the animal. Once we got close to the layer where the first bones were found, we switched to finer tools and more precise movements. Poking gently, removing small pieces and handfuls, and always, always, always keeping the site clean. As Ray and Andy kept telling us, “a clean site is a good site.” You have to constantly brush away the sand in order to see what’s there and avoid touching or damaging bone.
After about two hours of this, I finally found what I thought was a piece of bone. I called Paul over to look while I reached in to brush it off with a gloved finger. He reminded me to use the small paint brush; even my glove could scratch or damage it (watching Paul’s team work, you see the most interesting combination of brute force and delicate care). Gently and slowly, Paul brushed, picked and blew on the area until we could see the smooth surface of another vertebra – articulated with the last one. Victory!!!
When Gabe announced that it was time to break for the day we were all disappointed. If we could just dig for a big longer, we could see more of the animal and finally get a complete feel for it. I checked my watch (pushing the dust off it first to see the clock face) and was shocked to discover it was after 7:00 pm. The time had flown by. We sprinkled the exposed bones with hardener, covered the site with a blue tarp, weighted it down with rocks, and said good-bye to our bison. A team would come back to this site later and complete what we had started. Eventually, the bones would be meticulously covered in tin foil, cast in plaster, carefully lifted from the site, and even more carefully transferred back to Paul’s lab at University of Chicago.
We had our last dinner together at the Rainbow Room in Wibaux and then headed home to Glendive for the night. Tomorrow, we’d all be flying back to our homes and families. I knew we’d be taking a whole lot more back with us than dirty clothes and a few marine fossils carefully wrapped in our suitcases.
