Traces from an Ancient Desert Realm

Traces from an Ancient Desert Realm. . The tracks you can see along this short trail, and from the parking lot, were made by three-toed meat-eating dinosaurs. These tracks were formed along the edge of a lake that would have been found between dunes, in a vast sand dune sea, known as an erg. A high water table and springs fed these lakes, and as wind blew across the dunes the tracks and burrows of animals along the shoreline were gently buried in shifting sand and thus preserved. Many of the animals depicted in this enviromental reconstruction are based on trackway evidence. In this area, only two complete body fossils, Seitaad (a prosauropod, pictured here standing in the lake) and Segisaurus (a small theropod, pictured as a fleeing flock) have been found in the Jurassic-aged Navajo Sandstone. Skeletal remains of the large theropod that left the Eubrontes track type have yet to be found in the Navajo Sandstone, so the large predator pictured here is speculative, but based on other large theropods of similar age found elsewhere in the world. Traces of the plants and burrows depicted in this illustration have only been found in the Moab area., Captions , (Photo #1) Clam beds can be found at this site, indicating that these lakes were stable enough to support slow-growing aquatic life. , (Photo #2) A diversity of dinosaur tracks can be seen at this site, some as impressions, and some as positive casts made by overlying sediment filling in the impression. , (Photo #3) Grallator track surrounded by invertebrate burrows. , (Photo #4) Small animal burrows and the cavities left decaying plant stems were sometimes infilled by wind-blown sand, and are preserved as casts of the internal structure, later exposed as the surrounding sandstone erodes away., Illustrations and Photos by Brian Engh - dontmesswithdinosaurs.com