Amazing Concentration of Prehistoric Animal Tracks Discovered In Utah
The use of all terrain vehicles (ATVs) in the countryside can be a thorny issue. There are the drivers and enthusiasts who love the thrill of pitching themselves and their machines against what Mother Nature has to offer, whilst on the other side there are those folk who consider them to be noisy, intrusive beasts; leaving a trail of destruction wherever they go. Certainly, in parts of Southern England, such as the historic, ancient Ridgeway track on the South Downs; such vehicles have damaged the countryside, but in America, a popular off-roading area has provided scientists with a fascinating glimpse of life from the early Jurassic.
In Kane County, a part of Utah not far from the Arizona state line, scientists are busy studying a serious of fossilised trackways and individual footprints preserved in the sandstone sediments in an area popular with off-road riders. The site, which is south of the town of Mount Carmel, has revealed a large concentration of fossilised footprints, including prints from at least five different dinosaur species and three-toed crocodiles.
The prints are beautifully preserved and date back 190 million years to the lower Jurassic (Sinemurian faunal stage), a time when the dinosaurs were really beginning to diversify and dominate life on land. Amongst the finds discovered so far, are a series of huge footprints made by a giant plant-eating dinosaur (believed to be a prosauropod). Using estimates taken from the footprints themselves, as well as stride length, local palaeontologists believe the tracks were made by a dinosaur at least 12 metres long.
The site was reported to Bureau of Land Management workers in early November, and realising the significance of the site, the football field sized area was quickly fenced off to prevent further damage to the trackways from ATVs.
A team of scientists from the University of Colorado have been drafted in to map the area and to study the ecosystem that this concentration of fossil footprints reveal. After consulting with local ATV clubs the site has been closed in order to prevent any further damage to the fossils.
This particular location is very special as the sandstone has been deposited in fine layers and erosion has enabled some of the layers to be studied in depositional sequence, revealing the history of the ecosystem, like, as one palaeontologist put it “looking through a window in time”.
Although, during the Jurassic the super continent of Pangaea had started to break up, this part of Western North America was inland and in the process of being formed into part of the great, dry Laurasian Plains. The area was very arid and desert-like, with occasional rainy periods and flash floods that formed oasis. The footprints seemed to have been made over a considerable period of time as the rare rains provided the right muddy and sticky conditions for animal’s footprints to be preserved. The presence of large herbivores indicates that some time in the history of this area, there must have been a lot of rain that permitted large amounts of vegetation to establish and it was the plants that attracted these big herbivores into the area, whilst the newly formed lakes became home to crocodile-like animals.
Lower Jurassic sediments are not nearly as well researched and understood as geological formations from the late Jurassic, there are very few sites in the world that provide information about the ecosystems at this time in the Earth’s history and it is hoped that these trackways will help scientists understand more about the fauna around during the early Jurassic.