Rare Fossils From Extinct Jurassic Herbivore Discovered in Lake Powell, Receding Water Levels Expose New Layers of Rocks

While documenting fossil tracks near Lake Powell in Utah, paleontologists came across a bonebed which contains an extremely rare set of prehistoric fossils.

Rare and Significant Fossils

The fossils were discovered in Navajo Sandstone, a geological formation in the Glen Canyon National Recreation Area. The bonebed includes bones and teeth of a tritylodontid, an extinct mammal-like reptile which lived 180 million years ago.

Paleontologists found the rare fossils in March, an event which was believed to be in the right place at the right time. They happened to discover the bonebed while it was still accessible for a short period of time. This site is usually submerged and is replenished seasonally by snowmelt that flows down from the surrounding mountains through the Colorado River during the summer months.

Several hundred pounds of rocks containing fossil bones and skeletons were removed from the site. They will be taken to the University of Utah South Jordan Health Center where they will undergo X-ray and computerized tomography. Then they will be transferred to St. George Dinosaur Site at Johnson Farm for further analysis by laboratory and collections crew volunteers.

The fossils will become part of the Glen Canyon NRA museum collection which will be kept at the Prehistoric Museum in Price, Utah. This project is supported by the Petrified Forest National Park and the Smithsonian Institution.

The discovery can help the paleontologists in learning more about the survival of early mammal relatives during the mass extinctions at the end of the Triassic Period. It also gives insight on how these species diversified through the Jurassic Period.

Discoveries From Water Recession

The fossils are some of the most important discoveries in the U.S. this year. It does not only give researchers insight into the prehistoric species, but it also sheds light on the history of Lake Powell's changing shorelines.

In recent years, prolonged drought has been observed in Lake Powell which resulted in the recession of water levels. Although river flows have been low for many years, this year saw a record amount of snowmelt which accumulated through the wet winter.

Lake Powell is surrounded by large geological formations which contain a lot of uncovered fossils. The most famous and abundant fossils obtained from this area include the footprints of meat-eating dinosaurs in the Glen Canyon Group.

The series of sedimentary rocks were laid down by streams, lakes, rivers, and deserts from the Late Triassic Epoch through the Early Jurassic Epoch. One of the largest mass extinction events in the history of the Earth happened during this period.

The drought experienced in the southwestern region of the U.S. poses many concerns involving water shortage. However, the receding water levels in some lakes and reservoirs have unveiled some interesting findings. For instance, the declining water levels of neighboring Lake Mead in Nevada and Arizona have revealed several artifacts and shipwrecks. This has also occurred in other parts of the U.S. that experiences dry conditions.

Last year, footprints of dinosaurs from millions of years ago were unveiled in the midst of a severe drought in Texas. They were discovered in the Dinosaur Valley State Park in Glen Rose when the water levels of Paluxy River decreased due to hot temperatures.