Online Feature: Dingerland
Scrape the ground along Colorado’s Front Range and, chances are, you’ll find a dinosaur fossil. It happens often enough, from Fort Collins to Colorado Springs and east to Limon, that it’s hardly news anymore. Except when it is.
In August and September 2017, the Denver Museum of Nature & Science (DMNS) unearthed at a construction site in Thornton, with much media fanfare, one of the most complete dinosaur skeletons ever found in Colorado—several horns, shoulder blade, the beak at the front of the lower jaw, ribs, vertebrae, parts of the frill (shield of bones behind the head) and other small bones of Torosaurus, a close cousin of the Triceratops.
Among the fossils dating back thousands and millions of years that have been revealed during construction elsewhere in Colorado: Snowmass (mastodons and other ice age beasts), Littleton (a leg, shoulder blade, and three teeth from a Tyrannosaurus rex), third base at Coors Field (ribs of a Triceratops and the inspiration for the purple-and-polka-dotted team mascot Dinger—baseball parlance for home run), and DIA (prehistoric rainforest palm leaves).
Lesser known to nonscientists is a site on a ranch near Strasburg, an hour’s drive east of Denver, where DMNS paleontologists and interns have worked for several decades unlocking the secrets of what many scientists say is earth’s most recent extinction event—the impact of a six-mile-wide-or-more meteorite that crashed 66.03 million years ago, at 150,000 miles per hour, into the Yucatan peninsula, triggering a series of events that annihilated the dinosaurs and made possible the rise of humans.
The Strasburg ranch, known as West Bijou, is the only known site on the planet that reveals all the fingerprints of the disaster on Earth, and what came after, says Ian Miller, Ph.D., Director of Earth and Space Sciences at DMNS.
Miller recently attended a dedication of West Bijou as a National Natural Landmark, one of 599 in America. Other such landmarks in Colorado include Rocky Mountain National Park, Garden of the Gods, and Hanging Lake.
EnCompass interviewed Miller in his DMNS office recently to talk more about the history that West Bijou fossils and strata tell.
“The meteor that struck the Earth near Chicxulub, Mexico, pulled outer space to the surface of the planet, onto the top of the forests,” Miller said. “The impact crater was 110 miles across, and 12 miles deep. It liquefied the earth’s crust around the impact site, creating a peak ring in the middle, like the reverberation wave you see when a pebble falls into water.
“The impact’s shock wave traveled 5,000 miles per hour, reaching Alaska from Mexico in five minutes. A thermal pulse of more than 300 degrees baked the Earth, evaporating 2 centimeters of the earth’s oceans within the first few hours, supersaturating the atmosphere and creating floods of biblical proportions. The rain was acidic, because the meteorite had struck the margin of the sea, vaporizing deep sea muds, and nearshore coral reefs, made of calcium carbonate, converting them to carbon dioxide and releasing sulfur, poisoning the oceans and killing sea life. As finer debris spread through the atmosphere, the sky darkened, depriving all the earth’s forests of sunlight, collapsing them within two to 10 years.
“The meteorite killed 100 percent of the dinosaurs, and 80 percent of the mammal species,” Miller concluded. How could any living thing survive 300-degree temperatures, acid rain, and the demise of forests and the life they supported? “Soil is a great insulator,” Miller added, “so anything that burrowed under the ground, or stayed close to the ground, in super-wet vegetation, had a chance.”
The West Bijou site offers fossil evidence of all these events—the dinosaurs that roamed the land beforehand, the meteorite’s distinctive mineral fingerprint, the ash debris, the first plants to return, and more.
“The leaves of the first forests after the extinction event you find on the site—they’re pristine,” Miller said. “You don’t see chew marks. The insects hadn’t returned yet.”
Will the public be given access to the West Bijou site—a rugged ravine hidden from a nearby Arapahoe County dirt road? That decision is up to the land’s owner—a foundation that is hoping to avert another mass extinction event on earth by restoring short prairie grass in Colorado and ground cover elsewhere around the planet.
The Savory Institute promotes restoration of bare, overgrazed grasslands to help fix more carbon in the grasslands and allowing less carbon to rise into the atmosphere, where it inhibits heat from venting into space, raising global temperatures. To help restore perennial grasses at West Bijou, Savory partnered with a bison company, because the animals stir up the dirt with their hooves, which is beneficial, and their waste fertilizes the topsoil, which then supports life, such as dung beetles.
Of course, every bit of science in this story, such as the means of measuring time, and climate change, and the optimal way to repair grasslands, is challenged by other scientists and pundits.
Miller said there may be other sites across the planet that may contain as much information as the West Bijou site. But they’re not in an arid climate, with exposed rock, they haven’t been studied as closely, and they’re nowhere near an urban center like Denver.
“I’d estimate that fifty percent of what we know about paleontology was discovered in the American West,” Miller said. “Those of us who live here can drive to some of the best fossil deposits on the planet. The world comes to our backyard to study these sites.”
Perhaps Front Range residents will soon get their chance to see for themselves what scientists find so enlightening at West Bijou.