Copper Ridge Sauropod Dinosaur Tracks
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Thompson Copper Ridge Crescent Springs Alternating long and Junction short steps made by Exit –180 70 Sauropod Dinosaur a theropod with an Tracks irregular gait. SAUROPOD TRACK SITE (23 miles north of Moab) Footprints from the Morrison Formation Microwave tower ARCHES Credits 191 This site NATIONAL R E was discov- IV ered by Linda PARK R Dale Jennings 313 DO RA Lockley in 1989. LO CO Research and Moab brochure design by 279 the University of Colorado at Denver, Dinosaur Trackers Research Group and the Directions to Copper Ridge Bureau of Land Manage- ment. Fossil footprints are a From Moab, go north on U.S. Highway 191 for rare, non-renewable resource. 23 miles. Turn right 3/4 mile past milepost Please help to preserve and 148 (just north of the microwave tower). Cross protect them. the railroad tracks and follow the signs south on the dirt road. It is 2 miles to the tracksite from the highway. BUREAU OF LAND MANAGEMENT If coming from Crescent Jct. (I-70), turn left 1/4 mile past milepost 149, cross the railroad Typical tracks from the Morrison Moab Field Office tracks and continue south on the dirt road. Formation include those of 82 East Dogwood Moab, UT 84532 a brontosaurs The dirt road is suitable for passenger cars b large theropods BLM/UT/GI-99-008-8000 driven carefully. AVOID this road when wet. c small theropods Morrison Formation Sites Copper Ridge The Morrison Formation is one of the most The Copper Ridge Sauropod Tracksite was famous dinosaur-bearing deposits in the discovered in 1989. The site which is located world. It has yielded some of the best known north of the Moab airport, reveals the first Jurassic dinosaurs, including Apatosaurus or brontosaurus trackway reported from Utah, as “Brontosaurus”), Diplodocus, Stegosaurus well as trackways of four theropods of vari- and Allosaurus. Productive dinosaur quarries ous sizes. The dinosaurs walked in several in the Morrison Formation include Dinosaur directions across a ripple-marked sand de- National Monument and the Cleveland Lloyd posit that had accumulated in an ancient river Dinosaur Quarry. Skeletal remains of 150 channel. The brontosaur had large hind feet, million year old dinosaurs are very abundant about two feet in diameter, and smaller front in the Morrison Formation, but tracks are feet that did not leave such clear impressions. known from only about two dozen sites. The whole trackway makes a pronounced With the exception of the giant Purgatoire turn to the right. Such obvious changes of Valley tracksite in southeast Colorado, most direction are rare in fossil trackways. We do sites only yield a handful of three-toed tracks. not know which of the species of brontosaur This trackway is rare for its abundance of made these tracks. The most common types varying tracks. were Camarasaurus, Apatosaurus and Diplodocus. The three-toed tracks range from fifteen inches in length to about eight inches. The large trackmaker may have been Allosaurus, the most common carnivore in Morrison times. It is interesting to note that the track- way to the east shows an alternation of long steps (about 5 feet) and short steps (about 4 feet). No one knows the reason for this irregular gait - perhaps the animal was hurt and limping slightly. The smaller three-toed tracks, which are hard to see except in low angle light, could have been made by one of a number of smaller bipedal species. This map of the Copper Ridge Sauropod site Location of dinosaur tracksites in the shows trackways of a turning brontosaur and Morrison Formation of the Western USA. four carnivores..