'Jurassic San Juan' presentation set at library
FARMINGTON – Roughly 70 million years ago, the San Juan Basin looked much different than it does now.
The semi-tropical climate was much warmer and wetter than the temperate, dry, even desolate surroundings that exist today. Rather than miles and miles of largely barren sandstone bluffs and hoodoos, punctuated by tumbleweeds, juniper and cedar trees, the landscape featured plenty of rivers and ponds that supported a stunning variety of life. The oversized ferns, trees, flowers and grasses that covered the ground attracted enormous insects and served as a lush, green background for the area’s most interesting residents — dinosaurs.
Sherrie Landon, the paleontology coordinator for the Farmington field office of the Bureau of Land Management, will deliver a presentation on that time and place called “Jurassic
San Juan" on Thursday, Feb. 18 at the Farmington Public Library. Much of Landon’s PowerPoint presentation will focus on the November removal of two Pentaceratops fossils from the Bisti/De-Na-Zin Wilderness south of the city. But she also will spend a good deal of time describing what the climate and environment were like here during the late Cretaceous period and how it supported such outsized plant and animal life.
“There were a lot of flowering plants and tall ferns — it was an explosion of plant life,” Landon said of that era, explaining that many descendants of those plants still live in San Juan County today.
Landon’s presentation, which features 45 slides and is expected to last roughly an hour, will include images of those plants, as well as several that were taken when a pair of UH-60 Black Hawk helicopters were dispatched into the wilderness area a few months ago to haul out the two Pentaceratops fossils that had been excavated and placed in large plastered boxes in preparation for their trip to the New Mexico Museum of Natural History and Science in Albuquerque. The 73 million-year-old specimens represented the remains of a pair of five-horned herbivores discovered in 2011 and 2013 that once roamed the Four Corners.
Landon said one of the fossils came from a juvenile and is the first baby Pentaceratops ever found. For a variety of reasons, San Juan County is an excellent place to find such treasures, she said.
“It’s strictly controlled by what (geologic) formations are exposed and what the environment at that time was capable of preserving,” she said. “These animals have to live in an environment that favors rapid burial, like a swamp, where they could sink to the bottom and be covered.”
The late Cretaceous period in which the two Penceratops specimens lived was already past the peak of the dinosaur era, Landon said. The environment was becoming more temperate, and while plenty of them still roamed the earth, dinosaurs already had begun to die off, she said, while some nascent mammal species were beginning to show up.
“The vegetation was changing,” Landon said. “And there are a lot of hypotheses about why dinosaurs were already dwindling. But the majority of fossils on display at the Museum of New Mexico in Albuquerque are from San Juan County.”
Landon said that fact surprises most people, who look at the contemporary climate and surroundings of the San Juan Basin and wonder how they ever could have ever been home to such remarkable creatures.
Betty Decker, an adult services librarian at the library who is organizing Landon’s presentation, said the planned program already has piqued the interest of a number of library visitors for a simple reason.
“Everybody loves baby dinosaurs,” she said.
That human fascination with the now-extinct animals no doubt has been fanned by the “Jurassic Park” series of films — and accompanying flood of merchandise — but Landon said dinosaurs have always captured our imagination.
“Isn’t that funny?” she asked rhetorically, marveling at their size and other physical characteristics. “We have nothing living today that looks like them … It just fascinates people.”
Landon’s presentation won’t feature multi-million-dollar, CGI-crafted special effects of rampaging Tyrannosaurus rexes snapping their jaws as they track down terrified, fleeing humans. But it will provide a good picture of how the dinosaurs lived, what they ate and where they roamed.
Decker said you needn’t have a good background in natural history to enjoy the event.
“You will still be able to grasp this, even if you don’t know a lot about that (era),” she said. “She’s the perfect lady to be speaking about this.”
Landon said she periodically delivers such presentations, although she usually conducts them in the field for groups such as Boy Scouts. While San Juan County always has attracted researchers from around the country, she said she’s noticed a surge in local interest in dinosaurs ever since the twin Pentaceratops specimens were removed.
“The BLM is so pleased to get this (material) out into the public,” she said. “(The fossil removal) was so spectacular because of the use of the helicopters and the National Guard and the fact that they couldn’t land at the site … It’s been really good, and we’re seeing that a lot more people are calling here and asking where to go (to search for dinosaur fossils). And many of them are from outside the U.S.”
Many of the specimens recovered from this area also boast unusual head ornaments, Landon noted, and that kind of imagery also sparks the public’s imagination.
“The species of dinosaurs we have here are unique to our basin, and you don’t find them anywhere else,” she said.
The contemporary high desert environment and landscape would make it impossible for such imposing creatures to survive today. But Landon said she still enjoys taking a group of people into the field and challenging them to consider the secrets the landscape holds.
“People can look at the Bisti or the sandstone structures around here, and nothing’s growing,” she said. “But then they realize they’re standing on an ancient tropical environment.”
Mike Easterling is the A&E editor of The Daily Times. He can be reached at 505-564-4610.
If you go
What: “Jurassic Park San Juan,” a presentation by Sherrie Landon, the paleontology coordinator for the Farmington field office of the Bureau of Land Management
When: 6 p.m. Thursday, Feb. 18
Where: The Multipurpose Room at the Farmington Public Library, 2101 Farmington Ave.
For more information: Visit infoway.org or call 505-566-2203