BLM Reports Superb 2007 Paleontology Field Season at Grand Staircase-Escalante
After the field successes of the 2006 joint BLM-Utah Museum of Natural History(UMNH) Kaiparowits Basin Project, including the finding of two new genera of horned dinosaurs, one could hardly imagine it getting any better. And yet the 2007 field season exceeded the previous year in almost every regard. Critical financial support for a UMNH Assistance Agreement came through from the Utah State Office in Late Spring, and crews were immediately sent into the field. The first significant find of the season was made by Mike Getty, the UMNH collections manager who spotted a relatively complete skull of a Gryposaur hadrosaur. This was followed in May by a joint BLM-UMNH excavation of a 78 million year old hadrosaur from the Wahweap Formation. No diagnostic skull material was recovered, but public tours of the site while it was being worked created a great opportunity to highlight both the paleontological resources and the Monument.
Survey work in the spring by the joint BLM-UMNH team also led to the finding of the first articulated lambeosaur pelvis, tail and legs, as well as the partially articulated skeleton of a huge hadrosaur (probably a gryposaur) with skin impressions over much of the pelvic area. While the lambeosaur played out and apparently will not yield a skull, the large hadrosaur has yet to be tested. Another hadrosaur site found in 2005 by Dr. Alan Titus was tested near the end of the month and found to contain an associated skeleton of Parasaurolophus, including a partial skull that exhibits the distinctive tubular crest.
In June, a BLM team led by Dr. Titus, Grand Staircase-Escalante National Monument Paleontologist, tested a small basin of Kaiparowits Formation outcrop covered with large amounts of dinosaur eggshell. While the eggshell site did not preserve primary nesting features and was thus of only marginal scientific significance, the partial skull of a giant (estimated 30 feet in length) crocodile was found nearby by Dr. Titus. Collection of the upper jaw, which alone measured over two feet in length, took approximately a week. Preparation is ongoing and is taking place at the Monument HQ lab in Kanab. The largest tooth socket in the croc jaw is 53 mm in diameter indicating a huge 4-6 inch crown. Skull length almost certainly exceeded four feet and the body was over thirty feet long using the 7x-8x formula for head to total body length ratio. The importance of this specimen cannot be overstated. It is the largest known crocodilian from Utah, and it is the first record of a giant goniopholid-type dino-killing croc from anywhere in the world. Consultation with experts has determined this is one of the most important Cretaceous crocodilian finds ever.
Later in July and August, BLM volunteer Scott Richardson explored a basin in which no team had ever been in. He was rewarded with the discovery of two large horned dinosaur skulls, one of which was only the second specimen of the new GSENM taxon now informally referred to as “Chimeraceratops” because of its bewildering mix of cranial ornament. Also found nearby by Richardson and subsequent teams were several complete turtle shells, two partial ankylosaurs (armored dinosaurs) and several hadrosaur sites, most of which still require testing to determine overall significance. The second ceratopsid skull also has yet to be tested and its identity is unknown, although it appears it may be fairly complete. Near the end of July, a BLM-GSENM team led by Titus collected the remains of what promises to be the most complete Parasaurolophus skull known from Utah. The site, which had been found earlier in 2005 by Scott Richardson, apparently preserves much of the facial area for this species, which has never been described.
In early August, two articulated hadrosaur sites with large areas of skin impressions showing were found, along with an incredible amount of beautifully preserved microvertebrate material. Also some scattered fragments of a juvenile croc of large size, possibly a sub adult of the giant goniopholid found in June, were found.
August also saw the discovery of the most complete dinosaur skeleton ever recovered from the Kaiparowits, a nearly complete subadult ceratopsid that preserves the entire skull. Surface testing revealed that this world class specimen was associated with the remains of a small alligatoroid croc also with a nearly complete skull, another monument first! The identity of the ceratopsid specimen is still uncertain, but field observations, which need to be confirmed in the lab, indicate it is not “Chimeraceratops” or the other well known chasmosaur ceratopsid from GSENM. It is probably a third new genus and species from the Kaiparowits Formation, the first specimen of which was found by Eric Lund of the UMNH last summer. On a seemingly separate note, the UMNH team found the remains of a fossil or sub-fossil horse at the base of, you guessed it, Horse Mountain. Appearance of the material and its stratigraphic context created the possibility that the individual was more than 9,000 years old. Radiocarbon dating, made possible by the Regional Paleontologist (thanks Scott!), is currently underway to determine the exact age of this specimen.
In July, a team from the ALF Museum of Paleontology in Claremont, California managed to finish excavating the articulated partial hadrosaur that they found when they started digging a promising tyrannosaur site. Although it is fun to imagine the hadrosaur and tyrannosaur locked in mortal combat as a flood swept them away, this rare association of two totally different dinosaurs almost certainly resulted from pure coincidence. The good news is that when they finished removing the hadrosaur there was more tyrannosaur underneath. Unfortunately, the ALF team ran out of time (having had terrible luck with rainy weather) and the tyrannosaur will have to wait until next year. Other paleontology crews from the Oklahoma Museum of Natural History, UC Berkeley, Midwestern University, and the Los Angeles County Museum were also out this field season as well as a geologist from Northwestern University who is sampling paleobotanical materials for CO2 partial pressure data across the Cenomanian-Turonian extinction event.
Although the Cretaceous seems to grab all the attention, teams from Yale were also out this year continuing there ongoing work in the Triassic Chinle Formation, which records conditions not at the end, but at the very beginning of the dinosaur age. Dr. Walter Joyce, who led the effort, said the team found dozens of interesting sites, but nothing that rivaled the world class Poposaur find they made in the Circle Cliffs four years ago.
The climax of this field season was an airlift of almost 4,000 lbs of bones from five different sites by helicopter on September 21st. Among these are the Parasaurolphus skull, the body of the first “Chimeraceratops” found last year and the complete juvenile ceratopsid with croc found this year. All of this was made possible by generous support from the Kanab Field Office, Cedar City Fire Aviation, and Zion National Park. Thanks to all of you!! I want to emphasize that this kind of support is critical for specimen salvage because of the extremely rugged and remote nature of the Kaiparowits Backcountry. These dinosaurs just never seem to die near roads!
The Monument is also excited by the participation of two of our researchers (Dr. Jim Kirkland and Dr. Scott Sampson) in a special horned dinosaur conference in Alberta, Canada, where they are unveiling some of the new GSENM beasts to the scientific community!
In summary, the results of the 2007 Kaiparowits Basin Project exceeded the expectations of even the most optimistic crew members, providing not only a wealth of data that will keep researchers busy for the next decade, but also critical management information as to where and how the most significant resources occur. Over two thousand acres were surveyed, resulting in the documentation of at least two hundred fifty new fossil sites (more are still being added as I write). All in all a huge contribution both to public lands and Utah paleontology!
Source: BLM Utah
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