top of page

Jurassic Park

Updated: Jul 15, 2020

The Kaiparowits Plateau is a rich source of dinosaur bones for scientists in Grand Staircase-Escalante National Monument. Their work has uncovered a number of new species and contributed significantly to our understanding of the age of dinosaurs. It shouldn't come as a surprise then, that there are several areas in the monument that have dinosaur tracks.


Occasionally, the captions in my galleries on Grand Staircase-Escalante occasionally refer to the geologic strata (rock layers) visible in the monument. In general, younger rock layers are deposited on older ones. Although the monument's strata were deposited horizontally, they did not remain so. That is because the region was later subjected to powerful compressive stresses that forced the layers into immense folds.


Imagine a geologic fold as being like a standing rainbow with many colourful layers. If the rainbow were like the geology, the oldest layers would be on the underside, Layers would be younger and younger as you go to the top of the rainbow.


Now, imagine the forces of erosion acting (over geologic time) like a razor—cutting horizontally across the arc of the standing rainbow. If you could walk across the now-horizontal top of the standing rainbow, you would be walking first on the youngest layers, then progress to the oldest in the rainbow's center, and then cross younger and younger rock until you got to the other edge.


Grand Staircase-Escalante National Monument is a bit like that. The oldest rocks are in between the Circle Cliffs and get younger to the east and younger to the west as well.


Rock strata of the Colorado Plateau from the Grand Canyon to Bryce. Jurassic layers present in the Grand Staircase-Escalante National Monument but not shown on this schematic include (from oldest to youngest) Wingate, Kayenta, Navajo, Page, Carmel, Entrada, and Morrison. Diagrams from Ancient Landscapes of the Colorado Plateau by Ron Blakey (Colorado Plateau Geosystems, Inc.) and Wayne Ranney.


In the monument, dinosaur tracks are found in the Navajo and Entrada sandstone layers which are both in the Jurassic period. They are also found in the Straight Cliffs formation, which is in the Cretaceous period and thus younger.


Entrada formation near the town of Escalante. Photo © Donald J. Rommes


A large site in the Entrada formation is now well-known, but the area was rarely visited when I lived in the town of Boulder, Utah, before the monument was created. Local friends told me about dinosaur prints being somewhere on an outcropping of Entrada sandstone about twenty miles from the town of Escalante.


It took me a while to find them, but after I did, I returned with my 4x5 film camera and took the following image.


Hundreds of dinosaur tracks can be seen on this layer of Entrada sandstone. The footprints were moistened with water for visibility. Photo: © Donald J. Rommes.



The tracks were very difficult to recognise at first. That's because the tracks not really impressions or casts so much as concentric deformations of the sand on which the dinosaurs walked Once you begin to see them though, hundreds materialise from the rock. It is easy to imagine a lumbering beast walking across the sandy flats. Even though I have never seen a live dinosaur, these tracks bring home the fact of their existence.


At least two types of dinosaur prints are visible at this location. Tail prints (tail drags) are also visible. For more on the prints and their location, this description is helpful: https://digitalcommons.csbsju.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1020&context=compass


These prints, together with dinosaur fossils, help us acknowledge the reality of creatures no one has ever seen alive. They are vivid testimony to the fact that the world has been around for a very, very long time. Seeing them gives us an inkling of understanding of that immense amount of time—geologic time. But just as our hubris allows us to think we might actually comprehend geologic time, it is important to note that the rocks in which these tracks are found are among the youngest in the Escalante Canyons. Things get much. much older below.

Comments


Commenting has been turned off.
bottom of page