The colorful exposures of the Late Jurassic Morrison Formation near Hanksville, Utah.
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Photo by Brian Switek.
The colorful exposures of the Late Jurassic Morrison Formation near Hanksville, Utah.

Dinosaurs on Mars

I’ve never been to Mars, but I’ve been close. From my Salt Lake City home, the journey takes a relatively scant four and a half hours – through the smoggy sprawl of the valley and over lonely highways pocked here and there by small Utah farming towns before reaching the tourist-dependent outpost of Hanksville. I wonder how many people speed along the main drag, on their way to see the imposing geology of Capitol Reef National Park or make the spirit of Edward Abbey cringe by boating over Lake Powell, without ever realizing what lies up a unremarkable dirt road just a few miles outside of town.

Known as Cow Dung Road to the locals, the graded track snakes into hills banded in maroon, gray, and tan, set off in contrast by grey formations further beyond that ominously loom like the Black Gate. And plunked down in this landscape of strangely-shaded slopes and draws is a gleaming white structure just a quick left off the road – the Mars Desert Research Station.

The otherworldly geology of Utah’s San Rafael Swell may be the closest we get to Mars on Earth. Hollywood concurs. When Disney made their fumbling attempt at bringing Edgar Rice Burroughs’ Barsoom series to the screen, they selected a locale not so very far away to be a stand-in for the Red Planet.

As I bumped my rental car along the Bureau of Land Management road in the early June heat, part of a daily commute I traveled for almost a week, the tinges of Mars were only of passing interest. The scenery outside Hanksville is otherworldly, absolutely, but where many see Mars I envision spectacles that are more planetarily parochial yet just as strange. As the crew of John Carter found when they kicked up some stony scraps on their set, and as Hanksville locals have known for decades, the richly-colored badlands are permeated with what remains of dinosaurs that lived and perished over 148 million years ago. This is the closest we’ll ever get to an alien dinosaur, and the fossils were not an isolated lucky break. A quarry replete with the bones of Jurassic celebrities, not the Martian vistas, was what drew me out into the surreal outcrops.

No one knows who first discovered what is now known as the Hanksville-Burpee Quarry. (The site was going to be dubbed the Cow Dung Quarry after the road, but the humorless BLM requested a more dignified title. A shame.) Townsfolk and passers-by regularly found fragments of black and white bone as they wandered over the sun-baked sandstone around where the dig site is now established. A handful of paleontologists even took a passing interest in the locality, noting a rich accumulation of bones outside Hanksville in their letters and notes, but no one seemed particularly inspired to start sifting through what was out there.

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Paleontologist Scott Williams gives a tour of what was already been uncovered at the quarry when I arrived. Photo by Brian Switek.

By the time the Jurassic bonebed came to the attention of professional dinosaur experts, many major museums had already discovered, cataloged, and described much of the classic Morrison Formation fauna. Apatosaurus, Allosaurus, Barosaurus, Camarasaurus, Camptosaurus, Ceratosaurus, Diplodocus, Stegosaurus, and more – these dinosaurs were celebrities already well-known from famed graveyards such as those preserved at Bone Cabin Quarry, Wyoming and Dinosaur National Monument, Utah, many of which yielded their secrets during the “Second Jurassic Dinosaur Rush” of the early 20th century. For paleontologists and curators seeking new species to name and spectacular specimens to mount, yet another jumble of bones seemed rather mundane. The species encompassed in the stone outside Hanksville were probably all already known, and the prospect of spending years pulling out the remains of familiar Jurassic giants didn’t appeal to many museums.

But the Burpee Museum of Natural History, based out of Rockford, Illinois, wasn’t a venerable institution that already had stores overfull with Jurassic dinosaurs. A little more than six years ago, the institution started looking for sites that might yield suitably imposing dinosaurs for their exhibits. The Utah BLM directed them to the neglected Hanksville bonebed, where Burpee paleontologist Scott Williams and colleagues were instantly taken with the richness and expansiveness of the boneyard. The site could yield just the sort of charismatic dinosaurs they were hoping to excavate. In 2007, the Burpee Museum of Natural History started pulling the dinosaurs from the rock.

I had visited the site once before, in 2010, just to chat with Williams, sauropod expert Matt Bonnan, and their crew. But I returned this summer with every intention of getting my hands dirty. Once spring begins to creep into Utah, when snow is relegated to the high peaks around my valley home, I itch to go dig up dinosaurs. This year, I had nothing planned for June and worried that I wouldn’t have a chance to pick through the Mesozoic until much later in the summer. I needed dinosaurs, and soon. So I asked Williams, who I know runs his operation in Hanksville in early June, if he needed an extra hand. Fortunately for my Apatosaurus addiction, he agreed to let me get my fossil fix.

By fieldwork standards, the Burpee crew rolled in luxury. The experience was a sharp contrast with another excursion I took earlier this year. A few weeks before my journey to Hanksville, I got the unexpected chance to excavate dinosaurs in geologically younger rocks in Utah’s Grand Staircase-Escalante National Monument, further to the south. The situation is pack-in, pack-out: from food and shelter to plaster for making jackets and baby wipes (essential given the lack of showers in the backcountry), you must bring in everything you need and account for every scrap going out. Every few days, the crew might take the long ride into the nearest town to buy groceries and show respect to the close quarters in the quarries by taking showers at a KOA, but otherwise the camp has to be self-contained. But at Hanksville, some of the crew stayed in a trailer and others in the local motels. On the night I arrived, I pitched my tent near the laundry of the local campground – a facility with hot showers and a stone’s throw from the John Wayne-themed Slickrock Steakhouse. This was the height of luxury.

Actual quarry work was similarly cushy. Generators and air compressors squatted and thrummed on the exposed tufts of the quarry, creating constant white noise as they powered the vibrating microjacks – a hammering tool that looks like an insidiously oversized piece of dental equipment – that the volunteers and paleontologists pressed into the rock to free bone from sandstone. The crew had even set up shade – shade! – for heat-addled workers to take breaks and sip chilled Gatorade whenever they needed to. A field volunteer could easily get spoiled in conditions like this.

I never made use of the microjacks, though. As I quickly learned, my work was a little too delicate for such potentially destructive tools.

The Burpee crew had already been working the Hanksville quarry for a week by the time I arrived. Most choice spots were already taken. But, knowing that I have an affinity for menacing Jurassic carnivores, Scott Williams directed me to the sloping knob of the quarry where his crew has previously extricated the articulated vertebrae of a theropod dinosaur. Williams and colleague Josh Williams told me they suspected Allosaurus – a common Jurassic predator that could reach lengths in excess of 39 feet, armed with three-clawed hands and an airy skull full of serrated teeth – but the tri-horned, long-fanged Ceratosaurus was also a possibility. They were sure there had to be more of the predator on the side of the hill, so Williams told me to pick up a tool I’ve never used before in the field – a pushbroom.

The tools required to free a dinosaur from ancient sediment differ from site to site. At the last Utah excavation I blistered my hands assisting, field expert Mike Getty busted through concrete-tough swaths of sandstone with a jackhammer while the other crew members and I attacked the slightly softer rock with picks and shovels until we got down to the bone layer. At Hanksville, I accidentally started uncovering bone with the plastic broom. After pushing all the loose sediment off the side of the hill, making a suitably clean space to work, I looked down to see an oddly-shaped discoloration on the surface. The strange chunk had the texture of rotten wood. On my hands and knees, I could see more clearly – bone.

Freshly-exposed dinosaur bone usually isn’t very pretty. Limb bones that once supported the bulk of young sauropods – Camarasaurus? Apatosaurus? No one yet knew – exposed to the sun just to the right of my spot were mostly intact, but still split and cracked. My scrap was even worse off. The punky surface seemed to be run through with tiny rifts, making the fossil especially fragile. I needed vinac, and lots of it.

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The first bone of the season, with a 4-inch awl for comparison. Photo by Brian Switek.

A little brushing was enough to know that I had struck bone, but I had to stabilize the petrified mess before going any further. A mixture of acetone and polyvinyl acetate beads, vinac is an adhesive that penetrates bone and, after the acetone evaporates, leaves the plastic behind to hold the fossil together. I had mixed mine in a little jar earlier in the day, and had a little brush to apply the sticky stuff, but I didn’t even want to touch the bone lest bits of dinosaur come off on the hairs of the brush. Dribbling was the best I could do, trying to flick away some of the loose sandstone soon after so that the stone didn’t stick to the bone.

When visitors look over my shoulder in quarries or museums, many mention how tedious the work looks. Getting a fossil out of the ground or prettied up in the lab involves hours upon hours of separating prehistoric creatures from their encasing matrix. And while I suppose the repetitive task doesn’t look the most thrilling to an outsider, the joy of working on a dinosaur is that every piece of rock removed brings you a little closer to solving the conundrum of what you’re working on and where that piece fit in the skeletal puzzle of the living animal. As I carefully scratched the sandstone to see more of the bone I’d lucked across, the fossil thinned and ran back towards where I had been standing, pushing away sand, just a few minutes before. Through the process of scrape, brush, vinac, repeat, the fossil started to come into view.

I didn’t want to take the whole bone out. In the field, the goal is to find the extent of the bone or skeleton without fully preparing the specimen – that comes later, with more delicate tools, in the lab. And even though the odd shard was fragile, the fossil was small enough that I was hoping to dig a little trench around both sides, make a cap of wet paper towels and plaster-infused bandages, flip the bone over, and take the fossil out by the end of the day.

No such luck. The Hanksville-Burpee quarry is so dense that I struck more bone as I started to excavate around the first. Fair enough. I’d tackle the new bone first. Scrape, brush, vinac, scrape, brush, vinac, BONE. Again. Now I was beginning to feel conflicted. The first sign of a dinosaur in the rough always sends a rush of endorphins to my brain. But in such a tangled mass of bone, friable pieces laying under and around other bones quickly became the inspiration of enough frustration that the first word I repeatedly said upon striking them was not “Hooray!” but an expletive that I’m not allowed to print on this blog.

I spent four days going through this cycle. (I only took one day off to do some dinosaur sightseeing and replace my tent, which had irreparably collapsed during a midday wind gust.) During breaks, Williams would ask me how my “weirdness” was, to which I replied that I don’t have the health care coverage to afford mental therapy to alleviate my personality defects, and that the confusing muddle of fossils wasn’t helping. While other crew members were uncovering limb bones, pretty rib fragments, and even the back of a skull, I was left to toil with my mystery mess.

Chipping through stone on my stomach, side, knees, and an assortment of contortions required to keep my nose to the stone bones, I had plenty of time to think about what the fossils were and how they got there. The delicate pieces had the look of cervical ribs – the thin processes that jut out from neck vertebrae. But even if I was right, what species could they be from? And how could such delicate fragments survive the rough treatment of their deposition? The sandstone I scratched at more times that I could count was speckled with large pebbles from a prehistoric streambed where the quarry’s dinosaurs came to rest in a rotting heap. Such prominent stones were a hint of swift transport by fast-moving water.

What exactly happened at Hanksville-Burpee is only just beginning to be researched, but, as paleontologist Josh Matthews explained to me one especially hot morning, the deposit seems to be the remnant of a shallow channel where dinosaur bones were washed in by water flows of varying intensity over a period of who knows how many years. Perhaps, as was the case at other sites of Jurassic catastrophe, annual droughts killed parched animals and the bones of the dehydrated dinosaurs were all washed together when rains returned to the floodplains.

The question is why the Hanksville-Burpee quarry seems to be dominated by relatively young individuals of the long-necked, heavy bodied sauropod dinosaurs. There are some big bones in the quarry – the posterior part of a respectably-sized Allosaurus, limb elements from big sauropods – but many of the bones appear to be from juvenile and young subadult sauropod dinosaurs. After surveying the exposed fossils in the quarry during a morning visit, paleontologist and Jurassic expert ReBecca Hunt-Foster exclaimed “Your bones are so small!”

There’s still much to be found, but, as far as has yet been discovered, the site preserves an overwhelming abundance of dinosaurs that died especially young. Maybe this particular area was favored by young sauropods that traveled together – after all, the nutritional needs of young sauropods were different from those of adults and herding together might have made them less vulnerable to formidable carnivores of their era – but this is only speculative. The puzzle tickled and teased my mind as I went about extricating just a little bit more of a past I’ll never see myself.

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Bone, or not bone? The author at the Hanksville-Burpee quarry. Photo by May Blueotter.

I left my weirdness in the Jurassic. There was no conceivable way to safely remove any of the pieces before I had to leave for my next Jurassic stop, and I was finding new signs of bone until the very last minute. The dinosaur tidbits I had uncovered had waited over 148 million years in the rock. Waiting one more year cradled in sandstone won’t hurt them.

[I’m indebted to Scott Williams, Josh Matthews, Katie Tremaine, and the rest of the Burpee Museum of Natural History crew for letting me lend a hand during this year’s excavation. I’ll be back next year to finish what I started. Promise.]